STATE OF ANTARCTIC ENVIRONMENT

Transcription

1 FEDERAL SERVICE OF RUSSIA FOR HYDROMETEOROLOGY AND ENVIRONMENTAL MONITORING Federal State Budgetary Institution Arctic and Antarctic Research Institute Russian Antarctic Expedition QUARTERLY BULLETIN October December ( 81 ) STATE OF ANTARCTIC ENVIRONMENT Operational data of Russian Antarctic stations St. Petersburg 218

2 FEDERAL SERVICE OF RUSSIA FOR HYDROMETEOROLOGY AND ENVIRONMENTAL MONITORING Federal State Budgetary Institution Arctic and Antarctic Research Institute Russian Antarctic Expedition QUARTERLY BULLETIN October December ( 81 ) STATE OF ANTARCTIC ENVIRONMENT Operational data of Russian Antarctic stations Edited by V.V. Lukin St. Petersburg 218

3 Editor-in-chief A.V. Voyevodin (Russian Antarctic Expedition RАЭ) Authors and contributors: Section 1 Section 2 Section 3 Section 4 Section 5 Section 6 Section 7 Section 8 A.V. Voyevodin (RAE) Ye.I. Aleksandrov (Department of Sea-Air Interaction) G.Ye. Ryabkov (Department of Ice Regime and Forecasting) A.I. Korotkov (Department of Ice Regime and Forecasting) Ye.Ye. Sibir (Department of Sea-Air Interaction) Yu.G. Turbin, Ul yev V.А., L.N. Makarova (Department of Geophysics) S. G. Poigina, А.А. Kalinkin (FRC GS RAS) V.L. Martyanov (RAE) Please, address proposals and comments to: Arctic and Antarctic Research Institute, Russian Antarctic Expedition, Bering str. 38, St. Petersburg Tel.: (812) ; Fax: (812) lukin@aari.ru The Bulletin is posted in the Internet at the site of the FSBI AARI of Roshydromet at RAE pages in the section Quarterly Bulletin Arctic and Antarctic Research Institute (AARI), Russian Antarctic Expedition (RAE), 218

4 T A B L E OF C O N T E N T S PREFACE DATA OF AEROMETEOROLOGICAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS METEOROLOGICAL CONDITIONS IN OCTOBER-DECEMBER REVIEW OF THE ATMOSPHERIC PROCESSES OVER THE ANTARCTIC IN OCTOBER DECEMBER BRIEF REVIEW OF ICE PROCESSES IN THE SOUTHERN OCEAN FROM DATA OF SATELLITE, SHIPBORNE AND COASTAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS IN RESULTS OF TOTAL OZONE MEASUREMENTS AT THE RUSSIAN ANTARCTIC STATIONS IN GEOPHYSICAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS IN OCTOBER DECEMBER SEISMIC OBSERVATIONS IN ANTARCTICA IN MAIN RAE EVENTS IN THE FOURTH QUARTER OF

5 1 PREFACE The activity of the Russian Antarctic Expedition in the fourth quarter of 217 was carried out at five permanent Antarctic stations - Mirny, Novolazarevskaya, Bellingshausen, Progress and Vostok and at the field bases Molodezhnaya, Leningradskaya, Russkaya and Druzhnaya-4 and in the field camp Oasis. The work was performed by the wintering team of the 62 nd RAE and from November by the seasonal and wintering teams of the 63 rd RAE over a full complex of the Antarctic environmental monitoring programs. At the field bases Molodezhnaya, Lenigradskaya, Russkaya and Druzhnaya-4 and in the field camp Oasis, the automatic weather stations AWS, model MAWS-11, and automatic geodetic complexes FAGS operated. The Bulletin presents operational observation data. Section I of the Bulletin contains monthly averages and extreme data of standard meteorological and solar radiation observations carried out at constantly operating stations during October-December 217, and data of upper-air sounding carried out at two stations - Mirny and Novolazarevskaya once a day at. Universal Time Coordinated (UTC). In accordance with the International Geophysical Calendar, more frequent sounding during the periods of the International Geophysical Interval was conducted in 217 at h and 12 h UTC during October. According to the order of Roshydromet No. 174 of , introduction of the methodology of formation and transfer of the results of radio-sounding in the binary code FM-94 BUFR with the use of special software developed at the Central Aerological Observatory was performed at Novolazarevskaya and Mirny stations in the IV quarter. Stations began operational transfer of sounding data in the binary code FM-94 BUFR from 1 November 217. Sounding of the atmosphere at Mirny and Novolazarevskaya stations was carried out by means of the upgraded system AVK-1- AP EOL with the use of radiosondes AK2-2m. The program of upper-air observations for the IV quarter 217 was fulfilled for 99%. There were two gaps (due to meteorological conditions at Mirny station). The atmospheric pressure for the coastal stations in the meteorological tables is referenced to sea level. The atmospheric pressure at Vostok station is not referenced to sea level and is presented at the level of the meteorological site. Along with the monthly averages of meteorological parameters, the tables in Section 1 present their deviations from multiyear averages (anomalies) and deviations in f fractions (normalized anomalies (f-f avg)/ f). For the monthly totals of precipitation and total radiation, relative anomalies (f/f avg) are also presented. The statistical characteristics necessary for the calculation of anomalies were derived at the AARI Department of Meteorology for the period as recommended by the World Meteorological Organization. For Progress station, the anomalies are not calculated due to a short observation series. In connection with the instrument failure, the data on total ozone at Vostok station are absent. The Bulletin contains brief overviews containing assessments of the state of the Antarctic environment based on the actual data for the quarter under consideration. Sections 2 and 3 are devoted to meteorological and synoptic conditions. The review of synoptic conditions (section 3) is prepared on the basis of the analysis of current aero-synoptic information, performed at the AARI. The analysis of ice conditions of the Southern Ocean (section 4) is based on satellite data received at Bellingshausen, Novolazarevskaya, Mirny and Progress stations and on the observations conducted at the coastal Bellingshausen, Mirny and Progress stations. The anomalous character of ice conditions is evaluated against the multiyear averages of the drifting ice edge location and the mean multiyear dates of the onset of different ice phases in the coastal areas of the Southern Ocean adjoining the Antarctic stations. As average and extreme values of the ice edge location, the updated data are used which are obtained at the AARI for each month from the results of processing the entire available historical archive of predominantly national information on the Antarctic for the period 1971 to 25. Section 5 presents a review of the total ozone (TO) using measurements at the Russian Antarctic stations and onboard the R/V Akademik Fedorov during her voyage in Antarctic waters (south of 55 S). The measurements are interrupted in the autumn and winter period at the Sun s height of less than 5. Data of geophysical observations published in Section 6 present the results of geomagnetic measurements and measurements of space radio-emission at Mirny, Novolazarevskaya, Vostok and Progress stations. Section 7 of this issue publishes the results of seismic observations of the Federal Research Center "Geophysical Service of the Russian Academy of Science" at Mirny andnovolazarevskaya stations in 216. Section 8 is devoted to the main events of RAE logistical activity during the quarter under consideration.

6 2 RUSSIAN ANTARCTIC STATIONS AND FIELD BASES MIRNY STATION Ст. Мирный STATION SYNOPTIC INDEX METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL 39.9 m GEOGRAPHICAL COORDINATES = S; = 93 1 E GEOMAGNETIC COORDINATES = ; = BEGINNING AND END OF POLAR DAY December 7 January 5 BEGINNING AND END OF POLAR NIGHT No NOVOLAZAREVSKAYA STATION STATION SYNOPTIC INDEX METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL 119 m GEOGRAPHICAL COORDINATES = 7 46 S; = 11 5 E GEOMAGNETIC COORDINATES = ; = 51. BEGINNING AND END OF POLAR DAY November 15 January 28 BEGINNING AND END OF POLAR NIGHT May 21 July 23 BELLINGSHAUSEN STATION STATION SYNOPTIC INDEX 895 METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL 15.4 m GEOGRAPHICAL COORDINATES = S; = W BEGINNING AND END OF POLAR DAY No BEGINNING AND END OF POLAR NIGHT No PROGRESS STATION STATION SYNOPTIC INDEX METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL 14,6 m GEOGRAPHICAL COORDINATES = S; = E BEGINNING AND END OF POLAR DAY November 21 January 22 BEGINNING AND END OF POLAR NIGHT May 28 July 16 VOSTOK STATION STATION SYNOPTIC INDEX 8966 METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL 3488 m GEOGRAPHICAL COORDINATES = S; = E GEOMAGNETIC COORDINATES = ; = BEGINNING AND END OF POLAR DAY October 21 February 21 BEGINNING AND END OF POLAR NIGHT April 23 August 21 Field Base Molodezhnaya STATION SYNOPTIC INDEX HEIGHT OF AWS ABOVE SEA LEVEL 4 m GEOGRAPHICAL COORDINATES = 67 4 S; = 46 8 E BEGINNING AND END OF POLAR DAY November 29 January 13 BEGINNING AND END OF POLAR NIGHT June 11 July 2 Field Base Leningradskaya STATION SYNOPTIC INDEX HEIGHT OF AWS ABOVE SEA LEVEL 291 m GEOGRAPHICAL COORDINATES = 69 3,1 S; = ,2 E Field Base Russkaya STATION SYNOPTIC INDEX HEIGHT OF AWS ABOVE SEA LEVEL 14 m GEOGRAPHICAL COORDINATES = S; = ,9 E Field Base Druzhnaya-4 HEIGHT OF ABOVE SEA LEVEL GEOGRAPHICAL COORDINATES Field Camp Oasis (Bunger Oasis) 5 m = S; = E SYNOPTIC INDEX 8961 AWS HEIGHT ABOVE SEA LEVEL 9 M GEOGRAPHICAL COORDINATES = S; = E

7 3 1. DATA OF AEROMETEOROLOGICAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS OCTOBER 217 MIRNY STATION Table 1.1 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Mirny, October 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Sea level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 27. Prevailing wind direction, deg 11 Total radiation, MJ/m Total ozone content (TO), DU

8 Daily precipitation sum,mm Snow cover thickness, cm Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 4 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Mirny station, October 217.

9 5 Table 1.2 Isobaric surface, P hpa Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) Isobaric surface height, H m Temperatur e, T C Dew point deficit, D C Resultant wind direction, deg Resultant wind speed, m/s Wind stability parameter,% Mirny, October 217 Number of days without temperature data Number of days without wind data Anomalies of standard isobaric surface height and temperature Table 1.3 Mirny, October 217 P hpa (Н-Н avg), m (Н-H avg)/ Н (Т-Т avg), С (Т-Т avg)/ Т

10 6 NOVOLAZAREVSKAYA STATION Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Table 1.4 Novolazarevskaya, October 217 Normalized anomaly (f-f avg)/ f Sea level air pressure, hpa Relative anomaly f/f avg Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 27. Prevailing wind direction, deg 11 Total radiation, MJ/m Total ozone content (TO), DU

11 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 7 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow coverage (F). Novolazarevskaya station, October 217.

12 8 Table 1.5 Isobaric surface, P hpa Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) Isobaric surface height, H m Temperatur e, T C Dew point deficit, D C Resultant wind direction, deg Resultant wind speed, m/s Novolazarevskaya, October 217 Wind stability parameter,% Number of days without temperature data Number of days without wind data Anomalies of standard isobaric surface heights and temperature Table 1.6 Novolazarevskaya, October 217 P hpa (Н-Н avg), m (Н-H avg)/ Н (Т-Т avg), С (Т-Т avg)/ Т

13 9 BELLINGSHAUSEN STATION Table 1.7 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Bellingshausen, October 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Sea level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness (sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 22. Prevailing wind direction, deg 225. Total radiation, MJ/m

14 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 1 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Bellingshausen station, October 217.

15 11 PROGRESS STATION Table 1.8 Monthly averages of meteorological parameters (f) Progress, October 217 Parameter f f max f min Sea level air pressure, hpa Air temperature, C Relative humidity, % 56 Total cloudiness (sky coverage), tenths 7.1 Lower cloudiness(sky coverage),tenths 2.7 Precipitation, mm 1.6 Wind speed, m/s Maximum wind gust, m/s 25. Prevailing wind direction, deg 9 Total radiation, MJ/m

16 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 12 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Progress station, October 217.

17 13 VOSTOK STATION Table 1.9 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Vostok, October 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Station surface level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths... Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 15. Prevailing wind direction, deg 25 Total radiation, MJ/m Total ozone content (TO), DU - - -

18 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Air pressure, hpa 14 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, ground level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line, precipitation (E) and snow cover thickness (F). Vostok station, October 217.

19 15 O C T O B E R Atmospheric pressure at sea level, hpa (pressure at Vostok station is ground level pressure) Mirny Novolaz Bellings Progress Vostok (f-favg)/ f Air temperature, C Mirny Novolaz Bellings Progress Vostok (f-favg)/ f Relative humidity, % Mirny Novolaz Bellings Progress Vostok (f-favg)/ f Total cloudiness, tenths Mirny Novolaz Bellings Progress Vostok (f-favg)/ f Precipitation, mm Mirny Novolaz Bellings Progress Vostok f/favg Mean wind speed, m/s Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Fig.1.6. Comparison of monthly averages of meteorological parameters at the stations. October 217.

20 16 NOVEMBER 217 MIRNY STATION Table 1.1 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Mirny, November 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Sea level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 33. Prevailing wind direction, deg 11 Total radiation, MJ/m Total ozone content (TO), DU

21 Daily precipitation sum,mm Snow cover thickness, cm Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 17 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Mirny station, November 217.

22 18 Table 1.11 Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) Mirny, November 217 Isobaric surface, P hpa Isobaric surface height, H m Temperatur e, T C Dew point deficit, D C Resultant wind direction, deg Resultant wind speed, m/s Wind stability parameter,% Number of days without temperature data Number of days without wind data Anomalies of standard isobaric surface heights and temperature Table 1.12 Mirny, November 217 P hpa (Н-Н avg), m (Н-H avg)/ Н (Т-Т avg), С (Т-Т avg)/ Т

23 19 NOVOLAZAREVSKAYA STATION Table 1.13 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Novolazarevskaya, November 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Sea level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 34. Prevailing wind direction, deg 135 Total radiation, MJ/m Total ozone content (TO), DU

24 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 2 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow coverage (F). Novolazarevskaya station, November 217.

25 21 Table 1.14 Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) Novolazarevskaya, November 217 Isobaric surface, P hpa Isobaric surface height, H m Temperatur e, T C Dew point deficit, D C Resultant wind direction, deg Resultant wind speed, m/s Wind stability parameter,% Number of days without temperature data Number of days without wind data Anomalies of standard isobaric surface heights and temperature Table 1.15 Novolazarevskaya, November 217 P hpa (Н-Н avg), m (Н-H avg)/ Н (Т-Т avg), С (Т-Т avg)/ Т

26 22 BELLINGSHAUSEN STATION Table 1.16 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Bellingshausen, November 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Sea level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 21. Prevailing wind direction, deg 27 Total radiation, MJ/m

27 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 23 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Bellingshausen station, November 217.

28 24 PROGRESS STATION Monthly averages of meteorological parameters (f) Table 1.17 Progress, November 217 Parameter f fmax fmin Sea level air pressure, hpa Air temperature, C Relative humidity, % 58 Total cloudiness (sky coverage), tenths 6.9 Lower cloudiness(sky coverage),tenths 2.7 Precipitation, mm 12.7 Wind speed, m/s Maximum wind gust, m/s 23. Prevailing wind direction, deg 67 Total radiation, MJ/m

29 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 25 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Progress station, November 217.

30 26 VOSTOK STATION Table 1.18 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Vostok, November 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Station surface level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths... Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 15. Prevailing wind direction, deg 225 Total radiation, MJ/m Total ozone content (TO), DU

31 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Air pressure, hpa 27 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, ground level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Vostok station, November 217.

32 28 N O V E M B E R Atmospheric pressure at sea level, hpa(pressure at Vostok station is ground level pressure) Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Air temperature, C Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Relative humidity, % Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Total cloudiness, tenths Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Precipitation, mm Mirny Novolaz Bellings Progress Vostok f/favg Mean wind speed, m/s Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Fig Comparison of monthly averages of meteorological parameters at the stations. November 217.

33 29 DECEMBER 217 MIRNY STATION Table 1.19 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Mirny, December 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Sea level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 3. Prevailing wind direction, deg 11 Total radiation, MJ/m Total ozone content (TO), DU

34 Daily precipitation sum,mm Snow cover thickness, cm Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 3 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Mirny station, December 217.

35 31 Table 1.2 Isobaric surface, P hpa Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) Isobaric surface height, H m Temperatur e, T C Dew point deficit, D C Resultant wind direction, deg Resultant wind speed, m/s Wind stability parameter,% Mirny, December 217 Number of days without temperature data Number of days without wind data Table 1.21 Anomalies of standard isobaric surface heights and temperature Mirny, December 217 P hpa (Н-Н avg), m (Н-H avg)/ Н (Т-Т avg), С (Т-Т avg)/ Т

36 32 NOVOLAZAREVSKAYA STATION Table 1.22 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Novolazarevskaya, December 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Sea level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 26. Prevailing wind direction, deg 135 Total radiation, MJ/m Total ozone content (TO), DU

37 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 33 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow coverage (F). Novolazarevskaya station, December 217.

38 34 Table 1.23 Isobaric surface, P hpa Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) Isobaric surface height, H m Temperatur e, T C Dew point deficit, D C Resultant wind direction, deg Resultant wind speed, m/s Novolazarevskaya, December 217 Wind stability parameter,% Number of days without temperature data Number of days without wind data Anomalies of standard isobaric surface heights and temperature Table 1.24 Novolazarevskaya, December 217 P hpa (Н-Н avg), m (Н-H avg)/ Н (Т-Т avg), С (Т-Т avg)/ Т

39 35 BELLINGSHAUSEN STATION Table 1.25 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Bellingshausen, December 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Sea level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 25. Prevailing wind direction, deg 335 Total radiation, MJ/m

40 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 36 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Bellingshausen station, December 217.

41 37 PROGRESS STATION Monthly averages of meteorological parameters (f) Table 1.26 Progress, December 217 Parameter f f max f min Sea level air pressure, hpa Air temperature, C Relative humidity, % 65 Total cloudiness (sky coverage), tenths 6.4 Lower cloudiness(sky coverage),tenths 3.7 Precipitation, mm 19.4 Wind speed, m/s Maximum wind gust, m/s 3. Prevailing wind direction, deg 67 Total radiation, MJ/m

42 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Sea level air pressure, hpa 38 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, sea level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Progress station, December 217.

43 39 VOSTOK STATION Table 1.27 Monthly averages of meteorological parameters (f) and their deviations from the multiyear averages (favg) Parameter f f max f min Anomaly f-f avg Vostok, December 217 Normalized anomaly (f-f avg)/ f Relative anomaly f/f avg Ground level air pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Wind speed, m/s Maximum wind gust, m/s 14. Prevailing wind direction, deg 25 Total radiation, MJ/m Total ozone content (TO), DU

44 Daily precipitation sum,mm Snow coverage, tenths Relative humidity, % Surface wind speed, m/sec Surface air temperature, C Air pressure, hpa 4 А B C D E F Fig Variations of daily mean values of surface temperature (A, bold line), maximum (A, thin line), minimum (A, dashed line) air temperature, ground level air pressure (B), relative humidity (C), mean (D, thick line), maximum (D, thin line) values of surface wind speed, maximum wind gust (D, dashed line), precipitation (E) and snow cover thickness (F). Vostok station, December 217.

45 41 D E C E M B E R Atmospheric pressure at sea level, hpa (pressure at Vostok station is ground level pressure) Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Air temperature, C Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Relative humidity, % Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Total cloudiness, tenths Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Precipitation, mm Mirny Novolaz Bellings Progress Vostok f/favg Mean wind speed, m/s Mirny Novolaz Bellings Progress Vostok (f-favg)/σf Fig Comparison of monthly averages of meteorological parameters at the stations. December 217.

46 42 2. METEOROLOGICAL CONDITIONS IN OCTOBER-DECEMBER 217 Figure 2.1 characterizes the air temperature conditions in October-December 217 at the Antarctic continent. It presents monthly averages, their anomalies and normalized anomalies of surface air temperature at the Russian and non- Russian meteorological stations. The actual data of the Russian Antarctic Expedition contained in /1/ were used for the Russian Antarctic stations and data contained in /2, 3/ were used for the foreign stations. The multiyear averages of surface temperature for the period were adopted from [4]. In October as compared with September there was an increase of the number of stations with the above zero anomalies of mean monthly air temperature (Fig. 2.1). The center of the area of the above zero anomalies of air temperature was located in the inland part of East Antarctica Here at Vostok station, the air temperature anomaly was 5.8 С, 3.6. For Vostok station, October 217 became the warmest month for the entire observation period. Large above zero air temperature anomalies were also noted in the area of the South Pole at Amundsen-Scott station (4.3 С, 1.8 ) and in the western part of the Queen Maud Land at Novolazarevskaya station (2.8 С, 1.9 ). At these stations the past October was correspondingly the second and fourth warmest October for the entire operation period of the stations. Small (less than 1 ) below zero air temperature anomalies were observed in the coastal part of the Indian Ocean sector of East Antarctica. The maximum of them was recorded in the area of Casey station ( 2. С,.9 ). In November, the above zero air temperature anomaly spread almost over the entire territory of Antarctica. The center of the heat area remained in the inland part of East Antarctica in the vicinity of Vostok station (2.9 С, 1.9 ). For Vostok station, November 217 became the fifth warmest November for the observation period from In the area of the Ross Sea and in the north of the Antarctic Peninsula at the stations, small below zero air temperature anomalies were recorded. In December, at most stations in East Antarctica, the below zero air temperature anomalies were observed. The center of the area of the below zero air temperature anomalies was located in the coastal part of the Indian Ocean sector of East Antarctica in the vicinity of the Queen Mary Land. Here at Mirny station, the air temperature anomaly was 1.4 С, 1.6. For Mirny station, December 217 was the sixth coldest month for the entire observation period. In the area of the Antarctic Peninsula and the Queen Maud Land, small above zero air temperature anomalies were observed. The center of the heat area was near Novolazarevskaya station (.8 С, 1. ). The statistically significant linear trends of mean monthly air temperature in these months at the Russian stations were detected only at Vostok station (Figs ). The air temperature increase at Vostok station in November and December was correspondingly about 3. С and 1.5 С/6 years (Table 2.1). In the last decade one notes appearance of a tendency for the decrease of air temperature in November December at Bellingshausen station and in December at Vostok station. They are however statistically insignificant. The atmospheric pressure at the Russian stations in these months was characterized in these months by predominantly negative deviations from the multiyear average. And only in October at Novolazarevskaya, Mirny and Vostok stations, and in November at Bellingshausen station, positive air pressure anomalies were observed. The largest negative air pressure anomaly was recorded in December at Bellingshausen station ( 11.2 hpa, 2.2 ). Such low air pressure in December at Bellingshausen station was observed for the first time over the observation period from The statistically significant linear trends of mean monthly atmospheric pressure at the Russian stations in these months were observed in December at Bellingshausen, Mirny and Novolazarevskaya stations (Figs ). The air pressure decrease in December at Bellingshausen, Mirny and Novolazarevskaya stations was about 6.8 hpa/5 year, 4.2 hpa/61 years and 5.6 hpa/57 years, respectively. The amount of precipitation at all Russian stations in October, and in December was mainly below the multiyear average. Only in October at Bellingshausen station, the amount of precipitation was greater than the multiyear average by 5 %. In November, at Bellingshausen and Vostok stations, the amount of precipitation was around the multiyear average, and at Mirny and Novolazarevskaya stations, more intensive fallout of precipitation was recorded. Thus at Mirny station in this month the amount of precipitation comprised about two monthly averages and at Novolazarevskaya station about three monthly averages of precipitation. Of interest is the monthly amount of precipitation recorded in December at Vostok station, exceeding many times the multiyear average. An analysis of the case of such significant amount of precipitation showed that this was a result of precipitation blowing into the precipitation gauge.

47 43 Table 2.1 Linear trend parameters of mean monthly and mean annual surface air temperature Station Parameter I II III IV V VI VII VIII IX X XI XII Year Entire observation period Novolazarevskaya С/1 years % Р 95 Mirny С/1 years % Р 99 Vostok С/1 years % Р Bellingshausen С/1 years % Р Novolazarevskaya о С/1 years % Р 95 Mirny о С/1 years % Р 95 Vostok о С/1 years % Р Bellingshausen о С/1 years % Р Notes: First line is the linear trend coefficient. Second line is the dispersion value explained by the linear trend. Third line: P=1-, where is the level of significance (given if P exceeds 9%).

48 44 Peculiarities of meteorological conditions in 217 For characterizing the meteorological conditions in the territory of Antarctica in 217 let us consider the spatial distribution of the average for the seasons and for the year air temperature anomalies at the Antarctic stations. As the seasons, the calendar seasons were taken and the summer season included December of the previous year. Table 2.2 and Fig. 2.5 present the values of anomalies of mean seasonal air temperature at the Antarctic stations in 217. In the summer season, over the entire territory of Antarctica there was an area of above zero air temperature anomalies. The main center of the heat area was traced in the region of the South Pole. Here at Amundsen-Scott station, the air temperature anomaly was 1.9 С (1.6 ) (Table 2.2). At Amundsen-Scott station, the summer season 217 was the ninth warmest season from Table 2.2 Mean seasonal anomalies and normalized air temperature anomalies at the Antarctic stations, С Station Summer Autumn Winter Spring Summer Autumn Winter Spring Anomalies Normalized anomalies Amundsen-Scott Novolazarevskaya Syowa Mawson Davis Mirny Casey Dumont D Urville McMurdo Rothera Bellingshausen Orcadas Vostok Notes: 1) 1 summer season includes December of the previous year; 2) 2 bold print denotes the air temperature anomalies of 1.5 and more. In the autumn season, the above zero air temperature anomalies were preserved over much of Antarctica. The main center of the heat area was located in the eastern part of East Antarctica. Here in the region of the Adelie Land at Dumont D Urville station and on Victoria Land at McMurdo station, the anomalies of mean seasonal air temperature 2.9 С (1.9 ) and 2.5 С (1.6 ), respectively. Another heat area was observed in the vicinity of the Antarctic Peninsula with the center near Rothera station (2.7 С, 1.5 ). The autumn season at Dumont D Urville and McMurdo stations was the fourth and at Rothera station the second warmest season from The below zero air temperature anomalies were observed in East Antarctica. Here in the coastal zone of the Mac-Robertson Land and in the inland part, one noted small (less than 1 ) by value anomalies. In the winter season, the below zero air temperature anomalies were observed at most stations of East Antarctica. The cold center was in the vicinity of the Wilkes Land. Here near the Casey station the air temperature anomaly was 3.5 С, 1.9. The winter season 217 was the third coldest season at the station from The area of the above zero anomalies of mean seasonal air temperature was noted in the area of the Antarctic Peninsula and the Ross Sea. The largest above zero air temperature anomaly was recorded near Rothera station (3.7 С, 1.2 ). At Rothera station, the winter season 217 was the sixth warmest season from In the spring season, the above zero air temperature anomalies were recorded over much of the territory of Antarctica. The center of the area of the above zero air temperature anomalies was located in the inland part of the continent. Here at Vostok station, the air temperature anomaly comprised 2.7 С, 2. and at Amundsen-Scott station, it was 2.6 С, 1.6. For these stations the spring season of 217 became the third in a series of the largest values for the entire observation period. Small (less than 1 ) below zero air temperature values were noted at the stations in the area of the Antarctic Peninsula and in the coastal part of the Indian Ocean sector of East Antarctica. In general, for the year, the values of anomalies of mean annual air temperature are not large at most stations (see Fig. 2.1, Table 2.3). The center of the area of the above zero air temperature anomalies was located in the vicinity of the Antarctic Peninsula near Rothera station (1.5 С, 1. ). At Rothera station, the year 217 was the eighth warmest year for the entire observation period. In the coastal part of the Indian Ocean sector of East Antarctica, one observed an area of the below zero air temperature anomalies with the center in the region of the Wilkes Land. Here at Casey station, the air

49 45 temperature anomaly was.9 С,.9. For Casey station, the past year was the eighth coldest year for the entire observation period. Table 2.3 Mean annual air temperature (T С), its anomalies (ΔT С) and normalized anomalies (ΔT/σ) at the Antarctic stations in 217 Station T ΔT ΔT/σ Rank by decrease Rank by increase Largest anomaly Least Anomaly Amundsen-Scott (+1.9) 1983( 1.6) Novolazarevskaya (+1.6) 1976( 1.) Syowa (+2.2) 1976( 1.7) Mawson (+1.7) 1982( 2.2) Davis (+2.4) 1982( 2.4) Mirny (+1.9) 1993( 1.5) Casey (+2.5) 1999( 2.3) Dumont D Urville (+1.8) 1999( 1.5) McMurdo (+2.7) 1968( 1.5) Rothera (+3.) 198( 3.8) Bellingshausen (+1.8) 198( 1.5) Orcadas (+2.1) 198( 2.6) Vostok (+2.2) 196( 2.) Note: The Table contains in brackets the values of the largest and smallest anomalies observed at each station. In 217, new highest and lowest mean monthly air temperature values at the Antarctic stations were recorded (Table 2.4). Table 2.4 New highest and lowest mean monthly air temperature values at the Antarctic stations in 217, С Station New mean monthly maximum New mean monthly minimum Rothera (III) 1.2 C (2.7 С, 1.9 ) Mirny (VI) 2.7 C ( 5.3 С, 2.5 ) Vostok (X) 51.2 C (5.8 С, 3.6 ) Note: The anomalies and normalized anomalies are given in brackets. Considering the interannual changes of mean annual and average air temperature in some seasons for the period at separate stations (Table 2.5), one can note both general regularities in the changes covering significant territories of Antarctica, and manifestation of local peculiarities at specific stations. Estimates of the linear trends of winter air temperature at the Antarctic stations showed the above zero air temperature trends to prevail. The statistically significant positive trends are noted in the area of the Antarctic Peninsula and at the Atlantic coast (Rothera station, 4.8 C/61 years, Novolazarevskaya station, 1.2 С/57 years). The negative linear trends for the winter air temperature are detected only in the area of the South Pole, eastern part of the Indian Ocean coast and in the eastern part of the Indian Ocean coast. These trends are however statistically insignificant. In the spring season, the above zero trends are present over the entire territory of Antarctica. The statistically significant trends take place for temperature in the central part of the Indian Ocean coast (Davis station) and in the area of the Ross Sea (McMurdo station). At these stations, the air temperature increase was 1.7 С, 2.7 С/61 years. In the summer and autumn seasons the statistically significant increase of air temperature is still preserved in the area of the Antarctic Peninsula. At Rothera station, the increase of air temperature in the autumn season was 4.2 С/61 years and at Bellingshausen station, it was 1.2 С/5 years. In the inland regions a positive sign of the trend is also noted. Here, the largest trend value is recorded in the changes of summer air temperature at Vostok station (1. С/6 years). An insignificant air temperature decrease persists in the central part of the Indian Ocean coast in the summer and autumn seasons.

50 46 Linear trend parameters of mean seasonal and mean annual air temperature Table 2.5 Station Summer Autumn Winter Spring Year B x D B x D B x D B x D B x D Amundsen-Scott Novolazarevskaya Syowa Mawson Davis Mirny Casey Dumont D Urville McMurdo Rothera Bellingshausen Orcadas Vostok Amundsen-Scott Novolazarevskaya Syowa Mawson Davis Mirny Casey Dumont D Urville McMurdo Rothera Bellingshausen Orcadas Vostok Amundsen-Scott Novolazarevskaya Syowa Mawson Davis Mirny Casey Dumont D Urville McMurdo Rothera Bellingshausen Orcadas Vostok Note: The summer season includes December of the preceding year and January-February of the next year, Вх linear trend coefficient, С/1 yr; D dispersion value explained by the linear trend, %. In general, a positive linear trend is present in the changes of mean annual air temperature for the period at most stations of Antarctica. The statistically significant positive trends of mean annual temperature for the entire period are noted in the area of the Antarctic Peninsula (Rothera station, 2.7 C/61 years), in the Ross Sea area (McMurdo station, 1.6 С/61 years), at the inland Vostok station (1. /6 years). The tendency for the decrease of mean annual air temperature for the period is observed in the eastern part of the Indian Ocean coast (Dumont d Urville station), but it is insignificant statistically. In the last thirty years, almost at all stations of East Antarctica one notes appearance for the mean annual air temperature of the below zero linear trend. The above zero linear trend is preserved at the inland stations of Antarctica, in

51 47 the area of the Ross Sea and in the southern part of the Antarctic Peninsula. The statistically significant increase of mean annual air temperature is observed only in the area of the South Pole. Here at Amundsen-Scott station, the increase of mean annual air temperature was 1.2 С/3 years. In the last decade, the main increase of mean annual air temperature was recorded in the area of the Queen Maud Land. Thus, at Syowa station the linear trend value was 1.1 С/1 years. Over much of the rest of the territory of Antarctica in the past decade there is noted a decrease of mean annual air temperature. The maximum decrease of air temperature was observed in the area of the Wilkes Land (Casey station, 1.2 С/1 years) and in the southern part of the Antarctic Peninsula (Rothera station 1.3 С/1 years. Thus, the results of monitoring of meteorological conditions of Antarctica in 217 show preservation of longterm tendency for the increase of air temperature in the surface layer. However appearance in the last decades of the below zero tendencies at some stations indicate slowing of the warming process in the South Polar area. Fig Mean monthly and mean annual values of (1) surface air temperatures, their anomalies (2) and normalized anomalies (3) in October (X), November (XI), December (XII) and in general for 217 (I-XII) from data of stationary meteorological stations in the South Polar Area

52 48 Fig Interannual variations of anomalies of air temperature and atmospheric pressure at the Russian Antarctic stations. October

53 49 Fig Interannual variations of anomalies of air temperature and atmospheric pressure at the Russian Antarctic stations. November

54 5 Fig Interannual variations of anomalies of air temperature and atmospheric pressure at the Russian Antarctic stations. December

55 51 Fig Values of mean seasonal air temperature anomalies at the Antarctic stations in 217, С References: Atlas of the Oceans. The Southern Ocean. GUNiO МО RF, St. Petersburg, 25

56 52 3. REVIEW OF THE ATMOSPHERIC PROCESSES OVER THE ANTARCTIC IN OCTOBER DECEMBER 217 The present reviews use data on the circulation forms of the Southern Hemisphere. Let us remind the main definitions and characteristics of these forms. The method of typification of the periods of atmospheric circulation was proposed for the Northern Hemisphere by Professor G.Ya. Vangengeim [2] and was further applied to the classification of atmospheric processes of the Southern Hemisphere [3]. The detailed characteristics of the forms are given in the edition Atlas of the Oceans [1]. The examples of synoptic situations at different circulation forms are given in Fig. 3.1 on the surface [5] and altitudinal [7] charts for the reporting period. Fig Examples of synoptic situations (surface charts and charts of baric topography of the surface 5 hpa at the forms of atmospheric circulation Z (2 December 217), М а (3 October 217) and М в (13 October 217) in the Southern Hemisphere At the zonal circulation form one observes a weakly disturbed baric field. At the meridional circulation forms in the troposphere one observes stationary baric waves of large amplitude. The location of the altitudinal ridges and troughs at the circulation forms М а and М в principally differs. At form М а, two large high pressure ridges are formed at meridians of the South Atlantic and the Australian sector. Between them there is a low pressure trough above the southern part of

57 53 the Indian Ocean. Over the central part of the Pacific Ocean sector a high pressure ridge develops as a rule. At the atmospheric circulation form М в, the main are the high pressure ridges above the Indian Ocean and the eastern and western regions of the Pacific Ocean sector. Above the South Atlantic and the Australian sector, extensive troughs are formed at form М в, which can be dissected by secondary ridges. One should take into account that the entire multitude of synoptic conditions is not reduced to the ideal types of circulation. Each of the forms has its varieties. For example, a zonal circulation form can have a mid-latitudinal and high-latitudinal character, depending on the trajectories of cyclones and location of the polar front. Besides, at the disturbed zonality one can observe the developed ridges and troughs, which rapidly move from west to east. Also at the development of meridional circulation forms of the atmosphere ridges and troughs, insignificantly displaced from the average typical location, can be observed. However, the general analysis of the complex of genesis of the atmospheric processes and macro-circulation of the air masses based on surface and altitudinal data makes it possible to identify the main features of synoptic situation and refer it to the definite circulation form of the atmosphere. The obtained data on the basis of daily determination of the circulation forms allow us to identify the main structural features of the atmospheric processes, determine the main tendencies in their development both for the short periods and in multiyear trends. The period under consideration is a transient period from the winter to the summer season. At this time, significant changes of the hydrometeorological regime are revealed and cardinal modifications of the entire atmospheric circulation take place. In October, a significant dominance of zonal circulation was preserved at the rare development of the meridional atmospheric processes. However, the development of zonality often occurred in the form of rapidly moving from west to east baric ridges and troughs of large amplitude. The intensity of the atmospheric processes decreased. The rates of displacement of cyclones, especially at zonal processes, remained high. The most active cyclones deepened to hpa, and some cyclones even to hpa. The prevailing number of cyclones had a depth of hpa. The features of the end of the winter period appeared in the atmospheric circulation above the temperate and high latitudes of the Southern Hemisphere. The Antarctic High was displaced to the area of East Antarctica, where significant positive anomalies of mean monthly atmospheric pressure were noted, exceeding in some regions a standard deviation (more than 5 hpa). The pressure anomalies over the Antarctic Peninsula were negative (up to 2 4 hpa) [6]. Small above zero air temperature anomalies were recorded over much of the Antarctic [4]. The largest air temperature anomalies were recorded above the Queen Maud Land and the Antarctic Plateau. Table 3.1. Frequency of occurrence of the atmospheric circulation forms of the Southern Hemisphere and their anomalies (days) in October December in 217 Months Frequency of occurrence Anomaly Z M a M b Z M a M b October November December In November, for the first time during the year the frequency of occurrence of zonal and meridional circulation forms became close to mean multiyear values. The intensity of the atmospheric processes continued to decrease. The prevailing trajectories of cyclones passed along more southern routes, the circumpolar low pressure belt was located at higher latitudes and the polar front was displaced southward. This has determined the formation above the south polar area at the decreased Antarctic High of the area of negative pressure anomalies, which reached large values over many regions (more than 5 hpa). Approach of intensive cyclonic activity to the shores of Antarctica resulted in the increased transport to the Antarctic regions of relatively warm and moist air masses, where the above zero air temperature anomalies and increased amount of precipitation were noted. The excess of the air temperature multiyear average (up to +2ᵒС) spread over most inland regions. There was a seasonal air temperature increase over the Antarctic Peninsula and its mean values did not drop below 4ᵒС, and the minimum air temperatures reached a mark of 5, 55ᵒС only at Concordia station and at Dome Argus [8]. In November, in connection with a significant elevation of the Sun s height, the contribution of the insolation factor to the formation of the thermal regime in high latitudes and manifestation of orographic atmospheric phenomena significantly increased. At many Antarctic stations, fog was often noted. On the Antarctic Peninsula, one often observed rain and drizzle. Snow and ice melting began in many coastal regions of Antarctica. The drifting ice edge began to retreat

58 54 to the south and after the maximum in September October its area began to decrease. Thus, the seasonal change of the underlying surface influencing the development of the atmospheric processes began. In December, zonal atmospheric processes began to prevail again. Their frequency of occurrence was 2 days, which is by 7 days greater than the multiyear average. The most suppressed was form М а, and the meridional circulation form М в was at the level of mean multiyear values (Table 3.1). Intensity of the general circulation of the atmosphere was at typically low summer level. Only some active cyclones had a depth lower than 96 hpa. Similar to November, the area of the decreased atmospheric pressure compared to the multiyear average was preserved over the Antarctic. The average negative anomaly of the atmospheric pressure over all Antarctic stations was one of the most significant for the last years (more than 5 hpa). At the coastal Antarctic stations, the air temperature deviations from mean multiyear values were small and in some areas, they were around the multiyear average, which is typical of the summer period. The deviations were predominantly positive (up to 1ᵒС). The most extensive source of insignificant below zero anomalies of air temperature was formed above the Prydz Bay and at the coast of the Wilkes Land. In the inner regions the air temperature deviations were small and of different directions. In these regions, the air temperature values continued to increase and were observed within 3 35ᵒС and the minimum air temperatures were higher than 45ᵒС. Above most of the Antarctic regions one observed a typically summer weather: almost complete absence of storms, appearance of haze and even fog and rain above the Antarctic Peninsula was noted periodically for the whole month. Only at Dumont D Urville station, the wind comprised sometimes a speed of 2 3 m/s and on 31 December, a speed of 37 4 m/s was recorded. In the middle of December, the spring stratospheric modification began above the South Polar Area, the winter stratospheric cyclone began to destroy, the wind speeds became weaker and its direction began changing to the east one. The final modification to the summer stratospheric High took place only in the end of December, which is a late event. Assessing the year 217 in general, one can say that the main peculiarity of the atmospheric circulation was dominance of zonal processes over temperate and high latitudes of the Southern Hemisphere (preservation of the tendency of the last years). This can be well seen from the analysis of the diagram of the frequency of occurrence of the atmospheric circulation forms in the Southern Hemisphere (Fig. 3.2). The analysis of the atmospheric pressure field makes it possible to identify two main periods: summer-autumn, when an area of the elevated atmospheric pressure compared with the multiyear average was formed over the Antarctic and the following it period when an area of negative pressure anomalies was observed above the South Polar area. The air temperature background in the summer-autumn period and before the beginning of winter (December May) was increased in general. The mid-winter (June September) was colder than mean multiyear conditions, except for the relatively increased air temperature in July over most of the polar regions. June was one of the coldest months in East Antarctica for the last decades. In the end of the winter season and transition to summer (October December) the air temperature over much of the Antarctic was higher than mean multiyear air temperature I II III IV V VI VII VIII IX X XI XII Z Ma Mb Fig Diagram of variations of anomalies of the frequency of occurrence of the atmospheric circulation forms in 217

59 55 Among the local peculiarities of thermo-baric fields above the South Polar Area one can note the increased compared to the other regions frequency of meridional disturbances of the atmospheric circulation above the Pacific Ocean sector. One can also pay attention to the dominance during the whole year of the above zero air temperature anomalies over the Antarctic Peninsula. References: 1. Atlas of the Oceans. The Southern Ocean. GUNiO МО RF, St. Petersburg, 25; 2. Vangengeim G.Ya. Bases of the macro-circulation method of long-range meteorological forecasts for the Arctic. AARI Proc., 1952, v.34, 314 p. 3. Dydina L.А., Rabtsevich S.V., Ryzhakov L.Yu., Savitsky G.B. Forms of the atmospheric circulation in the Southern Hemisphere. AARI Proc., 1976, v.33,,p

60 56 4. BRIEF REVIEW OF ICE PROCESSES IN THE SOUTHERN OCEAN FROM DATA OF SATELLITE, SHIPBORNE AND COASTAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS IN 217 Throughout the whole year the sea ice extent of the Southern Ocean was much lower than the multiyear average, approximately by 1 mln km 2 in most months. By the end of the summer in February 217, the ice area decreased to 2.1 mln km 2 (Fig. 4.1), and in March, it increased only up to 3.5 mln km 2 due to a weak character of the new autumn ice formation. These are record low values, almost by 3% lower than the multiyear average. Fig Change of seasonal extremes of sea ice extent of the Southern Ocean (in deviations from the multiyear average of their mean monthly values in February and September) for the period [1]. The main cause is in the extreme two-fold decrease of the Pacific Ocean ice massif compared with a multiyear average in summer 217. In late February for the second time over half a century period, ice in the vicinity of Russkaya station disappeared at W (first in 211). The situation of full clearance was preserved here for extremely long time until the end of April. Simultaneously a large part of the water area of the Amundsen Sea was ice-cleared. The landfast ice-iceberg peninsula opposite the Thwaites glacier was partly broken and was reduced by half along 11 W. Only in the Bellingshausen Sea, the drifting ice belt pressed against the coast was stably preserved, being gradually extended by the Coastal current westward in the form of a tongue. The Atlantic massif in the Weddell Sea was also developed in summer slightly less than usually (approximately by 1%), being elongated in the meridional direction along the entire Antarctic Peninsula and spreading eastward to 35 W. Nevertheless in the middle of January, one observed a unique situation of short-term intensification of ice export from the massif body to the north along 55 W with its subsequent transport on 17 January to the west to Bransfield Strait. On the next day, old ice cake of the Weddell Sea began to be exported to Maxwell Bay and even to Ardley Bay, which was three months earlier on 18 October 216 finally ice-cleared. As a result, a band of non-ordinary close ice up to 2 m wide pressed against the shore was formed at the head of the bay in the middle of summer, which melted however by 27 January. The marginal seas of the western part of the Indian Ocean sector were distinguished by the decreased sea ice extent. The Commonwealth Sea was completely ice-cleared. In the Cosmonauts Sea, only narrow belt of drifting ice was preserved in the coastal zone at the place of the finally broken up landfast ice in February, including fast ice in Lutzow- Holm Bay. Almost a complete clearance of ice took place in the Lazarev Sea. A relatively early destruction of landfast ice

61 57 in the area of Novolazarevskaya station contributed to this. It began in Leningradsky Bay as early as in December and was finished in Belaya Bay in the end of February. In the seas of the eastern part of the Indian Ocean sector, on the opposite, almost more than by 7% of ice remained than usually in the form of solid close belt pressed against the coast. No usual break of this belt and connection with the open ocean of such coastal recurring polynyas as Tryoshnikov Bay and Vincennes Bay were observed. It is not by chance that numerous large segments of old landfast ice were not subject to breakup. Preservation of an extensive area of landfast ice on the basis of the Dibble iceberg tongue extending from 135 to 141 E determined absence of clearance of the entire D Urville Sea, and in particular of the area of the French station Dumont d Urville. However in the Commonwealth Bay located to the east, the landfast ice was broken up and exported by the end of February. One should also note the delayed for half a month breakup of landfast ice at the roadstead of Mirny station (Table 4.1). The unusually late breakup of landfast ice in the middle of March in the neighboring region of Prydz Bay near Progress station is obviously connected with the extraordinary situation of blocking of Vostochnaya Bay by numerous icebergs due to catastrophic calvings of the outlet glacier Dalk in 216. The expansion of the ice belt in the Southern Ocean during much of the winter was unusually uniform approximately 3 mln km 2 each month beginning from 6.8 mln km 2 in the end of April up to 13. mln km 2 in June. In the middle of April, there was final freeze up of the coastal water area in the areas of Progress and Mirny stations (Table 4.1), while in the vicinity of the Alexander I Land, on the opposite, complete destruction of the entire old landfast ice took place. In May, the predominantly zonal expansion of the Atlantic ice massif reaching 1 W in the east and 6 S in the north was observed. At this, the ice edge in the Lazarev and Riiser-Larsen Seas only approached the 65 th parallel, obviously due to restraining warming impact of the Weddell polynya. At the beginning of the month, the northern bay in the Larsen Ice Shelf (A) was covered by young fast ice, which in December 216 was cleared of multiyear fast ice. In the end of May there was an early final freeze up of Alasheyev Bay, even in spite of a still very narrow belt of drifting ice in the Cosmonauts Sea. The external northern ice edge over much of the Southern Ocean corresponded to the mean multiyear location, except for the Amundsen and Bellingshausen Seas where it was still located much more to the south, near 7 S. In June, the record low sea ice extent of the Pacific Ocean sector was preserved. The ice edge here only moved insignificantly to the north. One should however note the reconstruction in the Amundsen Sea of fast ice-iceberg peninsula near the Thwaites glacier. In the Atlantic sector the ice edge was stabilized over the entire area around 6 S. In the Indian Ocean sector, the ice belt moved to the maximum northward to the Mawson Sea, where the ice edge reached 61 S. In July, the sea ice extent of the Southern Ocean increased from 13. to 16.3 mln km 2. However in August, the expansion of the ice belt sharply became slower. Its area comprised only 17.6 mln km 2. In September, the sea ice extent did not practically change, as after reaching 18. mln km 2 by the middle of the month, it began at once to decrease. As a result, the size of the circumpolar ice belt for the first time in the last 3 years did not exceed 18 mln km 2, comprising on average for September 17.8 mln km 2. This is only by.1 mln km 2 greater than the absolute minimum, which was observed in It is remarkable that in 1986 in the west of the Weddell Sea a large ledge of the Larsen Ice Shelf (C) calved from its central part between 68 and 69 S with formation of a giant iceberg 1 9 km in size and the area of about 9 thousand km 2. In 217, the calving was repeated on 12 July destroying the iceberg segment between 67 and 69 S. The resulting iceberg А68А km (5.8 thousand km 2 ) became the largest iceberg of the existing ones nowadays. The main cause for the decrease of the Antarctic sea ice, which became evident from winter 215, is obviously the intensification of the warming effect of the Southern Ocean. In 217, it was revealed in the anomalously early development of the Weddell polynya. In the area of the Maud Rise (65 S, 3 E), an extensive (almost 2 thousand km 2 ) open water space appeared inside the ice belt already at the beginning of September. For the month the open water area increased to 4 thousand km 2, and together with the ambient zones of young and open ice the area of the Weddell polynya reached by the end of September approximately 3 thousand km 2. Not less convincing confirmation of the enhanced oceanic heating is a very warm winter in the area of the South Shetland Islands for the second year in succession. On King George Island in Ardley Bay, the temperature of the surface layer of the sea in winter 217 not once dropped below 1.6 С. Stable ice formation occurred on the extremely late dates in the middle of August (Table 4.1). It was stimulated as usual by the export to Bransfield Strait of ice and cold shelf waters from the Weddell Sea, but which was late on average by 3 months. With the end of this inflow in the middle of September, the first complete clearance from ice of Ardley Bay occurred a month earlier than usually. As a result, no landfast ice was formed here. For half a century operation of Bellingshausen station, this was observed only once in 24. The duration of the ice period turned out to be half as large as the multiyear average only about 2.5 months. It should be also noted that beginning from winter 215, the temperature of the sea surface layer in the vicinity of the Larsemann Hills in Prydz Bay does not drop below 1.8 С at the multiyear average of 1.9 С. However at the roadstead of Mirny station in Tryoshnikov Bay, the water temperature already from the middle of May comprised less than 1.9 С, being in the overcooled state less (by.2 С). This determined intensive formation of frazil ice up to the

62 58 end of the year, due to which the thickness of the local landfast ice comprised the maximum values, exceeding the multiyear average by 2% (Table 4.2). Table 4.1 Dates of the onset of main ice phases in the areas of the Russian Antarctic stations in 217 Station Landfast ice breakup Ice clearance Ice formation Landfast ice formation Freeze up (water body) Start End First Final First Stable First Stable First Final Mirny Actual NO 1) (roadstead) Multiyear NO avg Progress Actual NO NO (Vostochnaya Multiyear NO NO Bay) avg Bellingshausen Actual НБ НБ НБ НБ (Ardley Bay) Multiyear avg Note: 1) NO phenomenon not observed (does not occur) Table 4.2 Landfast first-year ice thickness and snow depth (in cm) in the areas of the Russian Antarctic stations in 217 Station Parameters M o n t h s II III IV V VI VII VIII IX X XI XII Ice Actual Mirny Multyear avg Snow Actual Multyear avg Ice Actual Progress Multyear avg Snow Actual Multyear avg At the general background of decreased sea ice extent of the Southern Ocean, the traditional opposition of the Pacific Ocean sector was especially pronounced. Here after the extreme clearance in summer and record low sea ice extent up to June, the ice belt by the end of winter (in the middle of September 217) recovered almost completely its size. In the east of the sector, ice spread even slightly more to the north than usually as a result of development from the beginning of July of the tongue of ice exported from the region of Marguerite Bay (7 W) in the direction of the Drake Passage. This ice reached King George Island only in the middle of September and at once began retreating back to the west. In the middle of September, in the area of Russkaya station near Cape Burks, the formation of a characteristic jugged ledge of fast ice began with the top on Aristov shoal, but which then until the end of the year was again completely destroyed. Simultaneously, there was establishment of landfast ice in the Commonwealth Bay in the D-Urville Sea, but it lasted only until the end of October. The freeze up of Malygintsev and Milovzorov Bays near the Shackleton Ice Shelf in the Mawson Sea was not observed at all. In October, the circumpolar ice belt did not have any changes its area comprised on average 17.7 mln km 2. The Ross polynya was developed only at the level of near-barrier polynya. The Weddell polynya also stopped externally its development. However it is in its area that the subsequent rapid melting-disappearance in December of an enormous ice mass was surreptitiously prepared under the immediate destructive impact from below of the deep oceanic heat supplemented from the above by the influence of solar radiation. For November, the sea ice extent of the Southern Ocean decreased up to 13.8, and by the end of December, it was reduced by half (!) up to 6.9 mln km 2, which is less than the multiyear average approximately by 1 mln km 2 (1%). As a result, the water area of the entire eastern part of the Atlantic sector between 1 W, and 2 E was almost completely cleared (Fig. 4.2). On the opposite in the Pacific Ocean sector, the sea ice extent was even slightly greater than the multiyear average (by 3%), mainly due to the decreased development of the Ross polynya. Besides, the massive belt of drifting ice was densely pressed against the shore in the Bellingshausen Sea for the third year in succession.

63 59 Fig Ice situation in the Southern Ocean in the middle of December 217 In the northwest of the Weddell Sea due to intensive ice export eastward from the body of the Atlantic massive, the ice clearance of the South Orkneys Islands was anomalously delayed until the end of the year. Unusually much ice was also preserved in most marginal seas of the Indian Ocean sector. The only exception was the D Urville Sea, where by December the main portion of landfast ice was already destroyed. One should also note the rarely observed easy conditions for navigation in Malygintsev and Milovzorov Bays near the Shackleton Ice Shelf in the Mawson Sea. In both bays, recurring polynyas were developed in the absence of landfast ice, and the external belt of drifting ice opposite the polynyas decreased in width up to 6 miles already by the middle of December and was strongly diverged (Fig. 4.3).

64 6 Fig Ice situation in the Mawson Sea opposite the Bunger Oasis in the middle of December 217 on Terra satellite image Fig Ice situation at the head of Prydz Bay in the area of Progress station in the middle of December 217 on Terra satellite image

65 61 A directly opposite heavy ice situation was formed by the end of December at the head of Prydz Bay in the area of Progress station (Fig. 4.4). Local landfast ice by the middle of November grew as usual up to 1.5 m and with the increasing temperature of sea surface layer from 1.8 to 1.7 С began slightly melting (Table 4.2). However mean daily air temperatures in the first part of December became again below zero and melting of landfast ice not only stopped but even was replaced by its insignificant growth. During this period there was formation of a giant breccia field from the local massif of continuous drifting ice, which was accumulated near the barrier of the Amery Ice Shelf and along the edge of the coastal band of landfast ice between 74 and 76 E. Before that the earlier drifting ice, moved mainly from east to west by the Coastal Slope Current although with great difficulty but rounded the protuberant front of the Amery Ice Shelf, which in the last years especially strongly protruded to the sea. A giant ice breccia field could not overcome it, was stuck and even was fastened with landfast ice. As a result, there was a double increase of the width of landfast ice in the area of 75 E (the width is usually about 4 km). This probably made significantly weaker the destructive potential of wave oscillations of the level in the area of the Larsemann Hills Oasis. The delay with the onset of ice breakup was intensified by an unusually large thickness of seaward part of landfast ice in the area of 76.5 E. Ice here was the most level with prevailing ice hummock and ridge concentration of 1 point as compared with the neighboring segments on both sides with ice hummock and ridge concentration of 3 4 points. However the thickness of this level first-year ice over the first 1 km along the planned transit route of the R/V Akademik Fedorov" was equal to 17 2 cm at the snow depth on it up to one meter. Besides, ice was very viscous due to moistening throughout the entire thickness. Therefore one had to refuse from forcing it and postpone for a month the ship approach to the station. Similar landfast ice level, snow-covered up to 1 cm and unusually thick (16 18, in places 2 cm), was encountered by the R/V Akademik Fedorov" at the western shore of Breidvika Bay in the Riiser-Larsen Sea in early December. Given its late formation (in June), achieving such thickness only for half a year is possible only due to intensive formation of frazil ice, which was really observed in a large quantity in the channel behind the ship. Thus, in the Southern Ocean during the period there was a gradual increase of sea ice extent, which noticeably increased at the beginning of the new millennium. The increase of sea ice extent was accompanied with worsening of navigation conditions, also due to the delay in the dates of landfast ice breakup. However expansion of sea ice was not monotonously progressive, but it developed at the background of polycyclic oscillations of sea ice extent. Moreover one observed in the Pacific Ocean sector in summer the directly opposite advancing processes of clearance, as a result of which its sea ice extent decreased by half reaching an unusually low level in the summer-autumn period 217. Thus the accumulated ice growth in the Southern Ocean only for the last two years was completely eliminated. The average residual sea ice extent by February 217 decreased to the record low value of 2.3 mln km 2, and in September, it comprised 17.8 mln km 2, insignificantly yielding to the minimum of References: 1).

66 62 5. RESULTS OF TOTAL OZONE MEASUREMENTS AT THE RUSSIAN ANTARCTIC STATIONS IN 217 In 217, regular measurements of total ozone (TO) at three Russian Antarctic stations Vostok, Mirny and Novolazarevskaya and during cruises of the R/V Akademik Fedorov to the Antarctic were continued by the AARI and RAE specialists. Processing and analysis of the information reported from Antarctica were performed. The results of TO monitoring are presented in the quarterly bulletins State of Antarctic Environment [1]. One should note absence of data from Vostok station in the review, connected with malfunction of the instrument. The available results of measurements of this station require an additional analysis after the return of the expedition. In the first part of 217, modification of the circulation processes from the summer type to the winter type occurred above the Antarctic as is usual at this time of the year. The circumpolar vortex formed in winter reached its maximum size (almost 31 mln km 2 ) at the beginning of August. This took place earlier than usually and the vortex area was smaller than its mean maximum value. After this the vortex began slowly to decrease and its complete destruction was by the middle of December. The meteorological conditions at the level of the ozone layer were sufficiently stable until the beginning of August, becoming very unstable by the day of the autumn equinox and then returning to the relatively stable state. The vortex often changed its shape and one observed brief temperature increases (in the end of the first and third 1-day periods of August, in the middle of September and at the beginning of October). The ozone hole was formed at the beginning of August in the area of the Antarctic Peninsula, mainly due to the dynamic factors. By the second week of September, the area of the hole comprised 2 mln km 2, which corresponds to the average value for the last decade. As the hole was becoming more elliptic, its area decreased and by the end of September it comprised only 11 mln km 2, which is much smaller than the size of the holes usually observed at this time of the year. The ozone hole existed until the middle of November, like in 216, but it was at this time already much less than in 216 and, correspondingly less than on average for the last decade [1-5]. Figure 5.1 presents mean daily values of total ozone, calculated for the entire period of observations and for the last three Antarctic seasons (from July 216 to June 217). Grey color denotes the area covering all TO values, observed for the specific day over the entire observation period (upper and lower boundaries of this area correspond to the maximum and minimum mean daily TO values). 1 averaged for the entire observation period mean daily TO values, 2 mean daily TO values in the season , 3 mean daily TO values in the season , 4 mean daily TO values in the season Fig Mean daily total ozone values at the Russian Antarctic Mirny and Novolazarevskaya stations. One can get acquainted with a more detailed description of TO change at the Russian stations during the first three quarters of 217 in the AARI RAE Quarterly Bulletins for 217 [1]. The total ozone concentration above Antarctica in the first half of the year was sufficiently stable at its some decrease throughout autumn. In the Antarctic summer and autumn, the mean monthly values at both stations were higher than in 216 (Table 5.1, [1]). In spring of 217, a significant decrease of total ozone was observed only at Novolazarevskaya station and even at this station, there were sharp TO fluctuations in September and in October (Fig. 5.1). At Mirny station, the TO fluctuations from day-to-day were even greater (for example for the period 16 to 21 September, the TO concentration increased more than 2-fold from 212 Dobson units to 488 Dobson units) and its values in in the spring period are higher than in 216. Such TO fluctuations are related to instability of the circumpolar vortex in 217 and changes of its size and shape. The mean daily TO values in spring at Novolazarevskaya station changed from 152 DU on 2 October to 387 DU

67 63 on 26 November. At Mirny station, these fluctuations comprised 488 DU on 21 September to 25 DU on 9 October. The minimum TO values at both stations were higher than in 216 [1]. Table 5.1 Statistical characteristics of mean daily TO values (Dobson units) at the Russian Antarctic stations in 217 January February March April August September October November December Mirny Average σ Maximum Minimum (9.1) Novolazarevskaya Average σ Maximum Minimum (2.1) The TO measurements were also carried out onboard the R/V Akademik Fedorov during her cruises to Antarctica and back. Figure 5.2 presents the TO values measured onboard the ship and the corresponding coordinates of the ship. The lowest TO values this year were noted in the end of March when the ship was in the area of Novolazarevskaya station. ОСО(е.Д.) Градусы Дата 1 TO, 2- latitude, 3- longitude Fig Latitudinal variations of total ozone concentration onboard the R/V Akademik Fedorov References: 1. Quarterly Bulletin State of Antarctic Environment. Operational data of the Russian Antarctic stations. FSBI AARI, Russian Antarctic Expedition , No

68 64 6. GEOPHYSICAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS IN OCTOBER DECEMBER 217 Analysis of geophysical materials of Antarctic stations for the fourth quarter of 217 Brief characteristics of solar activity The observation period October to December 217 is characterized by low solar activity. The values of solar radio-emission flux F1.7 at the wavelength of 1.7 cm changed within 6 8 W/m2. The maximum number of sun spots in some groups ranged within 2 3. At the time of the increase of eruptive activity the velocity of high-velocity solar fluxes was 6 km/s. The perturbations of the structure of the magnetosphere, caused by the passage of high-velocity solar fluxes and subsequent magnetic storms at the Earth s surface were weak. The first group of spots was observed from 1 to 16 October 217. The magnetic storm caused by this increase of eruptive activity was not strong and the value of magnetic index Dst = 57. The value of the PC magnetic index was about 4. The next group of solar spots was observed from 24 to 27 October. The magnetic storm caused by intensified solar activity was weak and the value of Dst = 46 and РС ~ 3. The next increase of solar activity was observed on 9 1 November. The magnetic storm related to intensification of this group of solar spots was moderate and the value of magnetic index Dst was equal to 75, and the PC index was 5. One more weak magnetic storm was from 21 to 23 November (Dst = 42, РС = 3). In December, there were several weak small magnetic storms: on 4 6 December (Dst = 37, РС = 4), on December (Dst = 22, РС = 2) and on December (Dst = 2, РС = 2). These data indicate that there were two periods, when the magnetic perturbation was very weak: from 1 to 9 November and in the second part of December 217. The amount of energy coming to the magnetosphere from the solar wind is characterized by the РС-index, developed at the AARI Department of Geophysics and adopted in August 213 at the 12 th session of the International Association of Geomagnetism and Aeronomy (IAGA) as a new international index of magnetic activity. Its values are calculated in the Department of Geophysics in real time and are presented in the form of a plot at the AARI site. The РСindex values exceeding 2 mv/m, determine the periods of increased sub-storm activity in the auroral zone (auroral magnetic activity) and increases of perturbation of the magnetosphere. Fig РС-index diagram for the period October to December 217 Figure 6.1 shows the diagram of РС-index for the period October through December. On this diagram, the increased values of РС-index clearly identify all periods of the magnetosphere passage through fluxes of high energy solar wind fluxes. Analysis of geomagnetic data

69 65 Observations of the level of perturbation of the Earth s Magnetic Field (EMF) in the fourth quarter of 217 were carried out at Vostok, Novolazarevskaya, Mirny and Progress stations under a standard program. During the period of seasonal activities of the 62 nd RAE (January 217), upgrading of the previous geomagnetic complex at Mirny station was carried out. The SPRL logger was disconnected and the quarz magnetic variation sensor was connected via the cable communication line to the ADC. The control of ADMVS is made from the PC-recorder using the Titov software. After disonnection of SPRL, sharp pips of values in the files Lemi-18 stopped. So it can be supposed that the cause of pips was functioning of unscreened logger plate. As shown by the data analysis for the fourth quarter of 217, and a comparison of the results of four quarters of this year, the quality of absolute observations can be considered good. The average for the quarter absolute values of the EMF components are calculated from data of measurements, which are carried out during each quarter when determining the basis values of variation stations. Each of the obtained values includes not only the value of the main Earth s magnetic field, but also the value of the field of magnetic variations that occurred at the time of conducting absolute measurements. For this reason the changes of mean quarterly absolute EMF values do not have a definite trend and can differ significantly between each other both by the numerical expression and by the sign. An analysis of the data of absolute values of the magnetic field components, obtained during the entire year will make it possible to assess the degree of their variability and error of the estimate of their mean annual values. The mean annual absolute values of the Earth s magnetic field components at the Antarctic stations are presented in Table 6.1. Station Mean annual absolute values of the EMF components in 217 Table 6.1 EMF components D H Z T Mirny Novolazarevskaya Vostok Progress As can be seen from the Table above, the magnetic field at Novolazarevskaya station differs significantly by the force components from the magnetic field of other Antarctic stations. Analysis of data of vertical sounding of ionosphere at Mirny station During the period under consideration October through December the illumination by UV emission of the ionosphere at the level of F-layer at Mirny station in Antarctica depended on the Sun s zenith angle. Therefore there should have been observed daily variations of critical frequencies of the F2- layer. Regretfully, these values of critical frequencies of the F2-layer in the daytime and nighttime hours are absent on the diagram for October almost for the whole month, except for several values in the end of the month. The absence of data for October indicates technical malfunction of the ionosonde for this period at the Antarctic Mirny station. It turned out that daily variations in November and December 217 at Mirny station are weakly discerned. The difference of daytime and nighttime values of critical frequencies comprises 1 MHz, and sometimes the night values exceeded the values of fof2 in the daytime. Usually at Mirny station, the critical frequency in the daytime exceeds the nighttime values by 2 MHz. The low values of critical frequencies at the day side of the Earth were observed at the beginning of November (3.5 5 MHz) and in the end of December (4 4.2 MHz) 217. At the beginning of November and in the end of December, a weak magnetic activity was observed, which was mentioned above. One can suggest that the structure of the magnetosphere under the conditions of weak magnetic perturbation was such that Mirny station on the day side of the Earth was in the polar cap under the conditions of weaker ionization and low values of the critical frequencies of the F2- layer. At the night side of the Earth, Mirny station could be at the boundary of the auroral oval even at low magnetic activity, where the ionosphere of Mirny station was influenced by corpuscular particles precipitating from the magnetosphere.

70 66 Thus, the absence of a clear daily difference in critical values on the day and night side of the Earth can be explained by a different position of Mirny station in the polar cap area in the daytime and in the area of the auroral oval at night with different sources of ionization in these areas. In November and December 217, the riometric absorption value was less than 1.5 db, which is characteristic of the periods of weak magnetic activity. However on the day side of the Earth, the reflections of the radio-signal from the F-layer were absent in the ionosphere even at the time of insignificant increases of riometric absorption. The absence of night reflections from the F-area during this period is connected with the increased auroral activity and signal absorption in the level of sporadic layers in the E-area of the ionosphere. Thus, the ionosphere data show that the ionosphere processes are closely connected with the magnetic perturbations occurring in the Earth s magnetosphere. The absence of data for October indicates technical faults of the ionosonde at Mirny station at this time. The analysis of performance of the ionosphere station of Mirny station based on the data obtained, showed that the instruments function without failure. The observations made correspond to the observation program. Analysis of riometer data A monthly set of the maximum (for each 24 h) absorption values was analyzed. The analysis presents an assessment of the work of riometers in general and the classification of riometer absorption increases depending on the factors influencing these increases. The increases with the amplitude greater than.5 db were analyzed.. The main abbreviations used in the analysis, are as follows: SPE (solar proton event) a phenomenon of the increase of solar proton fluxes after strong solar bursts, registered in the interplanetary space and in the Earth s magnetosphere; fluxes of protons with the energy of 1 MeV (in the integral measurement of F> 1 MeV) make the largest contribution to the absorption; during the analysis such SPE were considered, which had the maximum intensity of F max (Ep> 1 MeV) 1 particle/cm 2 *s *steradian. Exactly at such intensity the PCA type absorption with the amplitude higher than.5 db begins its manifestation. GP (geomagnetic perturbation) a phenomenon of the increase of geomagnetic activity; intensity of GP is assessed by the Кр index, which reflects a global character of geomagnetic perturbation; as a significant geomagnetic perturbation, the periods were considered where Кр 2. Exactly at such intensity, the AA type absorptions with the amplitude higher than.5 db begin to be manifested. QDC (quiet day curve) a non-perturbed level of the space noise registered by riometer. It is determined by a special algorithm. AA (auroral absorption) a phenomenon of anomalous increase of absorption determined by fluxes of magnetosphere electrons at the time of global or local geomagnetic perturbations. GA (geomagnetic activity) level of geomagnetic field perturbation. PCA (absorption of polar cap type) a phenomenon of anomalous increase of absorption determined by solar proton fluxes during the SPE. The absorption increases of the impulse character can be caused by the global factors (SPE and GP) or the local factors (local increase of geomagnetic activity, increase of the level of interference or malfunction of riometer work). The prolonged increased (or decreased) similar absorption values can be caused by riometer fault or inaccuracy of plotting the quiet day curve (QDC). The Internet data on the fluxes of solar protons (with the energy of 1 1 MeV) and on the level of geomagnetic activity (К р index) were used in the analysis. The maximum for the day absorption values were compared with variations of every minute absorption values presented at the site of the Department of Geophysics of the AARI. October Several periods of geomagnetic perturbations were registered during the month. Vostok (32 MHz). Significant increases of absorption are absent during the month. Mirny (32 MHz). Two periods of absorption increases are registered with the maximums on 14 and 26 October (amplitudes, Аmax = 1. db and 1.2 db, respectively), which are determined by fluxes of magnetosphere electrons at the time of the increased level of global and local GA.

71 67 Progress (32 MHz). During the month one observes three absorption increases with the maximums: on 1, 14 and 25 October (amplitudes, Аmax = 3.4, 3.3, 1.3 db, respectively), which present the AA phenomena and are governed by the fluxes of magnetosphere electrons at the time of the increase of global and local GA level. Novolazarevskaya (32 MHz). During the month one observes five periods of the increased absorption level with the maximums: on 1, 15, 19, 21, 26 October (amplitudes ranging Аmax = from 1. to 14. db). The increases are the AA phenomena and are governed by the fluxes of magnetosphere electrons at the time of the increase of global and local GA level. November Several periods of geomagnetic perturbations were registered during the month. Vostok (32 MHz). Increases of absorption are absent during the month. Mirny (32 MHz). During the month the absorption variations at the range of values of.3.8 db with periods of 3 7 days are observed. They are determined by the fluxes of magnetosphere electrons at the time of the increase of the global and local GA level. Progress (32 MHz). During the month one observes five absorption increases with the maximums: on 9, 13, 21, 24, 31 November (amplitudes А max = 1.6,.8,.8,.9,.9 db, respectively), which are the AA and are determined by the fluxes of magnetosphere electrons at the time of the increase of global and local GA level. Novolazarevskaya (32 MHz). During the month one mainly observed the increased absorption background. At this background, a series of absorption increases was registered with the maximums on 4, 11, 18, 25 and 31 November (amplitudes at the range of А max = from 1.1 to 2.7 db). These increases are the AA and are determined by the fluxes of magnetosphere electrons at the time of the increase of global and local GA level. December During the month one registered three prolonged periods of geomagnetic perturbations: on 4 6 December (РС = 4), on December (РС = 2) and on December (РС = 2) with the maximums: on 9, 18 and 21 December (the values of the index Кр = 4 +, 3 and 6, respectively). Vostok (32 MHz). During the month, the significant (more than.5 db) absorption increases are absent. Mirny (32 MHz). During the month one observes a wave-like change of the absorption level of space rays with the maximums: on 3, 14, 17 and 27 December (the amplitudes А мax =.6, 1., 1.3 and 1.2 db, respectively). These increases are the AA and are determined by the fluxes of magnetosphere electrons at the time of the increase of global and local GA level. Progress (32 MHz). During the month one observes five periods of increased absorption with the maximums on 1, 7, 17, 26 and 29 December (the amplitudes А max = 1.2,.9, 1.4, 1.2 and.8 db, respectively), which are the AA. The periods are determined by the fluxes of magnetosphere electrons at the time of the increase of global and local GA level. Novolazarevskaya (32 MHz). During the month one observes five periods of increased absorption with the maximums on 5, 11, 18, 25 and 31 December (the amplitudes А max = 2.6, 1.1, 2.4, 1.6, 1.9 db, respectively). All increases present the AA and are determined by the fluxes of magnetosphere electrons at the time of the increase of global and local GA level. The general monthly trend of the absorption change correlates well with the change of the global geomagnetic activity. Conclusions No PCA phenomena were registered during the period under consideration. Numerous AA phenomena were registered at all stations, except for Vostok station. The work of riometers for the period under consideration is characterized as follows: 1) At Vostok station, the riometer functioned normally; 2) At Mirny station, the riometer functioned normally; 3) At Progress station, the riometer functioned normally; 4) At Novolazarevskaya station, the riometer functioned normally.

72 68 DATA OF CURRENT OBSERVATIONS MIRNY STATION Mean monthly absolute values of the geomagnetic field Declination Horizontal component Vertical component October 89º1.1 W nt nt November 89º2.6 W nt 5773 nt December 89º2.5 W nt nt Basis values of IZMIRAN variometer Date D deg H nt Z nt Average values RMSD

73 69 Fig Maximum daily values of space radio-emission absorption at the 32 MHz frequency from data of riometer observations at Mirny station

74 7 Fig.6.3. Daily values of critical frequencies of the F2 (f F2)-layer at Mirny station

75 71 NOVOLAZAREVSKAYA STATION Mean monthly absolute values of the geomagnetic field Declination Horizontal Vertical component component October 29º59.1 W nt nt November 3º.5 W nt nt December 3º1.4 W nt nt Basis values of IZMIRAN variometer Date D deg H nt Z nt Average values RMSD

76 72 Fig Maximum daily values of space radio-emission absorption at the 32 MHz frequency from data of riometer observations at Novolazarevskaya station

77 73 PROGRESS STATION Mean monthly absolute values of the geomagnetic field Declination Horizontal Vertical component component October 79º52. W nt 5933 nt November 79º51.5 W 1699 nt 5916 nt December 79º48.3 W nt 591 nt Basis values of LEMI-22 variometer Date D deg H nt Z nt Average values RMSD

78 74 Fig Maximum daily values of space radio-emission absorption at the 32 MHz frequency from data of riometer observations at Progress station

79 75 VOSTOK STATION Mean monthly absolute values of the geomagnetic field Declination Horizontal Vertical component component October 124º35.3 W nt nt November 124º31.5 W nt nt December 124º29.3 W nt 5773 nt Basis values of IZMIRAN variometer Date D deg H nt Z nt Average values RMSD

80 76 Fig Maximum daily values of space radio-emission absorption at the 32 MHz frequency from data of riometer observations at Vostok station

81 77 7. SEISMIC OBSERVATIONS IN ANTARCTICA IN 216 In 216, seismic observations in Antarctica, carried out from 1962, were continued at the stationary Novolazarevskaya station of the Federal Research Center "Geophysical Service of the Russian Academy of Science" (FRC GS RAS). The observations were carried out by a three-component broadband seismometer SKD in a set with a 16- charge digital seismic station SDAS, developed and produced in the FRC GS RAS (Obninsk) jointly with the Scientific-Production Association "Geotekh / [1]. These instruments with the bandwidth of.4 5 Hz, sampling rate of 2 readouts a second and dynamic range of about 9 db allow applying a modern digital level of collection, storage and processing of seismic records [2]. The digital records of earthquakes were computer-processed and were archived on compact-disks, which upon the return of the expeditions were passed to the archive of the FRC GS RAS. Processing of digital records of earthquakes at Novolazarevskaya station was carried out on computer by means of the WSG software, developed at the FRC GS RAS [3], in accordance with the methodology [4] and included identification of arrivals of seismic waves, determination of the time and precision of arrivals, identification of seismic waves and determination of the main parameters of earthquakes (time in the source, distance to the epicenter and magnitude). The interpretation results were recorded in the electronic database, on the basis of which daily operational reports were prepared and sent to the Information-Processing Center (IPC) of the FRC GS RAS. These data were used for summary processing of earthquakes in preparation of 1-day Seismological Bulletins of the FRC GS RAS [5]. From 1 January to 31 December 216, Novolazarevskaya station registered 3447 arrivals of seismic events. Full processing was performed with determination of the main source parameters for 745 earthquakes. Data of Novolazarevskaya station were used at the IPC of the FRC GS RAS in 216 for summary processing of 478 earthquakes, of them 8 with the magnitude MPSP 6., including 17 with MPSP 6.5 (Table 7.1). Table 7.1 presents main parameters of strong earthquakes in 216, based on the data of Seismological Bulletins of the FRC GS RAS [5] and it is shown, which of them were registered at Novolazarevskaya station. No. Table 7.1 Earthquakes with a magnitude MPSP 6., registered at Novolazarevskaya station from 1.1 to Date dd.mm Time at the source (by Greenwich) hh:mm:ss Epicenter coordinates Depth h, km MPSP Region Epicentral distance to station NVL (, ) :: West Indian-Antarctic Ridge 2) :5: Myanmar India border area + 3) :38: Talaud Islands, Indonesia ) :45: Southwest Indian Ridge :25: Hokkaido region, Japan :13: Qinghai, China :6: Near the coast of Jalisco, Mexico :3: South Alaska :: Tonga Islands :22: Strait of Gibraltar :1: Region of New Ireland, P.N.G :25: East coast of Kamchatka :57: Taiwan :19: Solomon Islands :33: Coast of Central Chile :2: Sumba region, Indonesia :7: Region of the South Sandwich Islands :26: Region of Volcano Islands, Japan :49: Southwest of Sumatra, Indonesia :6: Andreanof Islands, Aleutian Islands :35: Andreanof Islands, Aleutian Islands :26: Windward Islands :5: East coast of Kamchatka :1: Fox Islands, Aleutian Islands :39: South coast of West Honshu :23: Vanuatu Islands :58: Vanuatu Islands :45: Java, Indonesia :32: Vanuatu Islands :14: South Sumatra, Indonesia +

82 No. Date dd.mm Time at the source (by Greenwich) hh:mm:ss Epicenter coordinates Depth h, km 78 MPSP Region Epicentral distance to station NVL (, ) :28: Afghanistan Tajikistan border area :55: Myanmar India border area :26: Kyushu, Japan :11: Near the coast of Chiapas, Mexico :25: Kyushu, Japan :45: Kyushu, Japan :58: Coast of Ecuador :6: Vanuatu Islands :33: Java, Indonesia :57: Coast of Ecuador :46: Coast of Ecuador :14: Northern Territory, Australia :38: Region of Fiji Islands :46: Region of South Sandwich Islands :14: Kermadec Islands, New Zealand :55: South Sumatra, Indonesia :25: Banda Sea :35: Kermadec Islands, New Zealand :51: Near the coast of Jalisco, Mexico :15: North of the Molucca Sea :13: South of Sumbawa, Indonesia :25: Nicaragua :17: Solomon Islands :17: Tajikistan Xinjiang border area :57: Near the east coast of Honshu, Japan :3: Java, Indonesia :11: Coast of Ecuador :11: Region of Kermadec Islands :13: Vanuatu Islands :4: Vanuatu Islands :18: Mariana Islands :33: Region of South Sandwich Islands :42: South of the Indian Ocean :24: Region of Volcano Islands, Japan :26: Southeast of Loyalty Islands :32: Region of South Georgia :45: Region of South Georgia :36: Central Italy :34: Myanmar :48: South Sumatra, Indonesia :29: North of Ascension Island :11: New Ireland Region, P.N.G :38: Near the east coast of North Island, N.Z :4: North Sumatra, Indonesia :38: Mindanao, Philippines :8: North Peru :31: Vanuatu Islands :21: Southeast of Honshu, Japan :14: Near the east coast of Honshu, Japan :53: Mindanao, Philippines :28: Area of Fiji Islands :19: Ryukyu Islands, Japan :51: Taiwan region :3: New Britain region, P.N.G :14: New Britain region, P.N.G :14: Tibet :25: Java Sea :7: West Honshu, Japan :25: Kuril Islands :15: Turkmenistan :18: Central Italy :17: Molucca Sea 99.

83 No. Date dd.mm Time at the source (by Greenwich) hh:mm:ss Epicenter coordinates Depth h, km 79 MPSP Region Epicentral distance to station NVL (, ) :26: New Ireland Region, P.N.G :4: Central Italy :2: Chile Argentina border area :2: South Island, New Zealand :32: South Island, New Zealand :: La Rioja Province, Argentina :34: South Island, New Zealand :3: Tonga Islands :1: Java, Indonesia :57: San Juan Province, Argentina :59: East coast of Honshu, Japan :43: Near the coast of Central America :24: Tajikistan Xinjiang border area :23: Near Islands, Aleutian Islands :13: Banda Sea :42: Leeward Islands :3: North Sumatra, Indonesia :15: North Xinjiang, China :49: Near the coast of North California :38: Solomon Islands :51: New Ireland region, P.N.G :27: New Ireland region, P.N.G :46: Solomon Islands :3: Peru Brasilia border area :21: Solomon Islands :17: Banda Sea :43: Region of Mariana Islands :58: New Ireland region, P.N.G :22: South Chile :38: East coast of Honshu, Japan :3: Sumbawa region, Indonesia 87.2 Total registered earthquakes with MPSP Total earthquakes participating in summary processing with MPSP 6. 8 Notes: 1) MPSP magnitude characteristic of the earthquake force, which is calculated from measurements of amplitudes and periods in the maximum phase of the longitudinal Р wave on the records of short period instruments (SP short period) and corresponds to the international magnitude mb; 2) results of processing of the given earthquake are absent in the station log; 3) + results of processing of the given earthquake are present in the station log, they are not included to the summary processing due to different reasons; 4) 11.6 (Epicentral distance in degrees) shown for parameters of the sources, in the summary processing of which this station participated. Most of the epicenters of earthquakes recorded at Novolazarevskaya station are situated in the Southern Hemisphere in the areas within the Pacific Ocean seismic belt /7/, a significant number is located in the territory of Indonesia, Vanuatu, New Zealand, South America, South Sandwich Islands, South Shetland Islands, Solomon Islands, Santa-Cruz Islands and Atlantic and South-Pacific oceanic ridges (Fig. 7.1 а). During processing of the records of earthquakes at the station, the coordinates of the epicenters were rarely determined and with a large error, so for construction of charts (Fig. 7.1а) these data were adopted from the Seismological Bulletin [5] and the Electronic Catalogues of the IDC (International Data Centre Vienna, Austria) and NEIC (National Earthquake Information Center, USA Geological Survey), from the site of the International Seismological Center ISC (Great Britain) [7]. The analogues in the indicated sources were not found for all seismic events in the station log at [5, 7] and therefore, the epicenters of only 123 earthquakes with m b 4.6 were mapped. According to data [7], two earthquakes occurred in the continental part of Antarctica in 216 (they are denoted by arrows in Fig. 7.1 b): on 4 September at 16 h 25 m at Sovetskoye Plateau (coordinates: 8.4 S, E) with m b=4.6 and on 21 January at 2 h 49 m in the area of the Nimrod Glacier (8.72 S, E) with m b=3.4. Two weak earthquakes were noted at the coast of McMurdo Bay: with m b=3.2 on 6 December at 12 h 22 m (75.38 S, 16.7 E) and with m b=3.5 on 1 November at 3 h 2 m (71.81 S, E, area of Cape Ader). The registration capacities of Novolazarevskaya station did not allow registration of these earthquakes ( = ).

84 8 a) b) magnitude of MPSP (mb); 2 seismic station. Arrows show the epicenters of earthquakes in the territory of Antarctica from data in [7]. Fig. 7.1 Charts of the epicenters of earthquakes, recorded by Novolazarevskaya station in 216 on the Earth (a) and in the area of the seismic belt of Antarctica (b) [6] from data in [5, 7]. All observation materials (compact disks) and the results of processing the data (reports and databases) obtained at Novolazarevskaya station are stored in the archive of the FRC GS RAS (Obninsk) and are provided on request to a wide range of users. The authors acknowledge the help of the staff of the FRC GS RAS Dr. V.F.Babkina and Dr. O.P. Kamenskaya in preparation of the materials to the article.