STATE OF ANTARCTIC ENVIRONMENT

Transcription

1 FEDERAL SERVICE OF RUSSIA FOR HYDROMETEOROLOGY AND ENVIRONMENTAL MONITORING Russian Federation State Research Center Arctic and Antarctic Research Institute Russian Antarctic Expedition QUARTERLY BULLETIN 2 (19) April - June 2002 STATE OF ANTARCTIC ENVIRONMENT Operational data of Russian Antarctic stations St. Petersburg 2002

2 FEDERAL SERVICE OF RUSSIA FOR HYDROMETEOROLOGY AND ENVIRONMENTAL MONITORING Russian Federation State Research Center Arctic and Antarctic Research Institute Russian Antarctic Expedition QUARTERLY BULLETIN 2 (19) April - June 2002 STATE OF ANTARCTIC ENVIRONMENT Operational data of Russian Antarctic stations Edited by V.V. Lukin St. Petersburg 2002

3 Authors and contributors Editor-in-Chief - M.O. Krichak (Russian Antarctic Expedition (RAE) Department) Section 1 - M.O. Krichak (RAE) Section 2 - Ye.I. Aleksandrov (Department of Meteorology) Section 3 - V.A. Belyazo (Department of Long-Range Weather Forecasting) Section 4 - A.I. Korotkov (Department of Ice Regime and Forecasting) Section 5 - Ye.Ye. Sibir (Department of Meteorology) Section 6 - I.P. Yeditkina, R.Yu. Lukianova, I.V. Moskvin, A.V. Frank-Kamenetsky (Department of Geophysics) Section 7 - N.I. Fomichev (RAE) Section 8 - V. Ye. Lagun, S.V. Yagovkina (Department of Air-Sea Interaction) Section 9 - V.A. Kuchin, V.V. Lukin (RAE) Translated by I.I. Solovieva Editor-in-Chief M.O. Krichak Russian Antarctic Expedition, Quarterly Bulletin. Acknowledgements: Russian Antarctic Expedition is grateful to all AARI staff for help and assistance in preparing this Bulletin. For more information about the contents of this publication, please, contact Arctic and Antarctic Research Institute of Roshydromet Russian Antarctic Expedition Bering St., 38, St. Petersburg Russia Phone: (812) Fax: (812) lukin@raexp.spb.su

4 CONTENTS PREFACE DATA OF AEROMETEOROLOGICAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS METEOROLOGICAL CONDITIONS IN ANTARCTICA IN APRIL-JUNE ATMOSPHERIC PROCESSES ABOVE THE ANTARCTIC IN APRIL-JUNE BRIEF REVIEW OF ICE PROCESSES IN THE SOUTHERN OCEAN FROM DATA OF SATELLITE AND COASTAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS IN APRIL-JUNE RESULTS OF TOTAL OZONE MEASUREMENTS AT MIRNY STATION IN THE SECOND QUARTER OF GEOPHYSICAL OBSERVATIONS AT RUSSIAN ANTARCTIC STATIONS IN APRIL JUNE SPATIAL-TEMPORAL VARIABILITY OF THE HYDROCHEMICAL SEA WATER PARAMETERS IN THE COASTAL ZONE OF ARDLEY BAY (BELLINGSHAUSEN STATION AREA) IN THE SUMMER PERIOD ON METHANE MEASUREMENTS IN ANTARCTICA MAIN RAE EVENTS IN THE SECOND QUARTER OF

5 1 PREFACE The Bulletin is prepared on the basis of data reported from the Russian Antarctic stations in real time via the communication channels. The Bulletin is published from 1998 on a quarterly basis. Section I in this issue contains monthly averages of standard meteorological and actinometric observations and upper-air sounding at the Russian Antarctic stations for the second quarter of Standard meteorological observations are carried out at the present time at Mirny, Novolazarevskaya, Bellingshausen and Vostok stations. The upper-air sounding is performed once a day at UT at two stations - Mirny Observatory and Novolazarevskaya (During May 2002, no upper-air sounding was undertaken at Novolazarevskaya station due to modernization of the AVK measurement complex). More frequent sounding is conducted at both stations during the International Geophysical Intervals (IGI) in accordance with the International Geophysical Calendar. The meteorological tables present the atmospheric pressure referenced to sea level for the coastal stations and to the station level for the inland Vostok station located at a height of 3488 m. Along with the monthly averages of meteorological parameters, the tables also present their departures from multiyear averages (absolute anomalies), normalized anomalies (departures in σ f fractions - (f-f avg )/ σ f ) and relative anomalies (f/f avg ) of monthly sums of precipitation and total radiation. The statistical characteristics necessary for calculation of anomalies were derived at the AARI Department of Meteorology for the period as recommended by the World Meteorological Organization. The Bulletin contains brief overviews with an assessment of the Antarctic environment state based on actual data. Sections 2 and 3 are devoted to the meteorological and synoptic conditions. The analysis of ice conditions of the Southern Ocean (Section 4) is based on satellite data received at Bellingshausen, Novolazarevskaya and Mirny stations and observations conducted at the coastal Bellingshausen and Mirny stations. The anomalous character of ice conditions is evaluated against the multiyear averages of the drifting ice edge position and the onset of different ice phases in the coastal areas of the Southern Ocean adjoining the Antarctic stations. The multiyear averages were obtained at the AARI Department of Ice Regime and Forecasting over the period Section 5 contains as usual, an overview of the total ozone (TO) based on measurements at the Russian stations. Data of geophysical observations published in Section 6 present the results of measurements in Mirny Observatory and at Vostok station under the geomagnetic and ionospheric programs (magnetic and riometer observations). Data of riometer observations are presented as the plots of the maximum daily values of space radioemission absorption at the 32 MHz frequency. Geophysical information also includes the magnetic activity index (PC-index), which is calculated on the basis of geomagnetic observation data at Vostok station. Section 7 presents an article of N.I. Fomichev devoted to the ecological activities at Bellingshausen station, namely to the study of physical-chemical water characteristics in the coastal part of Ardley Bay as this area presents a sewage water dumping site of the Russian Bellingshausen Base and the Chilean Frei Base. Section 8 publishes an article of V.Ye.Lagun and S.V.Yagovkina on the methane measurements at the Russian Antarctic stations with a comparison of measurement data of the Russian and foreign stations. The last Section of the Bulletin (9) deals traditionally with the main directions and events of the logistics activity of RAE during the period under consideration.

6 Russian Antarctic stations in operation in April - June MIRNY OBSERVATORY STATION SYNOPTIC INDEX METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL 39.9 m GEOGRAPHICAL COORDINATES ϕ = S; λ = E GEOMAGNETIC COORDINATES Φ = ; = BEGINNING AND END OF POLAR DAY 7 December 5 January BEGINNING AND END OF POLAR NIGHT No NOVOLAZAREVSKAYA STATION STATION SYNOPTIC INDEX METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL 119 m GEOGRAPHICAL COORDINATES ϕ = S; λ = E BEGINNING AND END OF POLAR DAY 15 November - 28 January BEGINNING AND END OF POLAR NIGHT 21 May - 23 July BELLINGSHAUSEN STATION STATION SYNOPTIC INDEX METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL 14.3 m GEOGRAPHICAL COORDINATES ϕ = S; λ = W BEGINNING AND END OF POLAR DAY No BEGINNING AND END OF POLAR NIGHT No VOSTOK STATION STATION SYNOPTIC INDEX METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL 3488 m GEOGRAPHICAL COORDINATES ϕ = S; λ = E GEOMAGNETIC COORDINATES Φ = ; = BEGINNING AND END OF POLAR DAY 21 October - 21 February BEGINNING AND END OF POLAR NIGHT 23 April - 21 August PROGRESS STATION METEOROLOGICAL SITE HEIGHT ABOVE SEA LEVEL GEOGRAPHICAL COORDINATES BEGINNING AND END OF POLAR DAY BEGINNING AND END OF POLAR NIGHT 64 m ϕ = S; λ = E 21 November 21 January 28 May - 16 July

7 3 1. DATA OF AEROMETEOROLOGICAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS APRIL 2002 MIRNY OBSERVATORY Table 1.1 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f April 2002 Relative anomaly f/f avg Sea level pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 158 Total radiation, MJ/m Total ozone content (TO), DU Isobaric surface, P, hpa Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) Isobaric surface height, H m Temperature, T C Dew point deficit, D C Resulting wind direction, deg Resulting wind speed, m/s Wind stability parameter Number of days without temperature data Table 1.2 April 2002 Number of days without wind data

8 4 Anomalies of standard isobaric surface heights and temperature Table 1.3 April 2002 P, hpa Н-Н avg, m (Н-H avg )/σ Н Т-Т avg, С (Т-Т avg )/σ Т NOVOLAZAREVSKAYA STATION Table 1.4 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f April 2002 Relative anomaly f/f avg Sea level pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 135 Total radiation, MJ/m Total ozone content (TO), DU * * Data of TO measurements require quality control and will not be published until it is done.

9 5 Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) Table 1.5 April 2002 Isobaric surface, P, hpa Isobaric surface height, H m Temperature, T C Dew point deficit, D C Resulting wind direction, deg Resulting 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 April 2002 Table 1.6 P, hpa Н-Н avg, m (Н-H avg )/σ Н Т-Т avg, С (Т-Т avg )/σ Т

10 6 BELLINGSHAUSEN STATION Table 1.7 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f April 2002 Relative anomaly f/f avg Sea level pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 315 Total radiation, MJ/m VOSTOK STATION Table 1.8 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) April 2002 Normalized Relative anomaly anomaly f/f (f-f avg )/σ avg f Parameter f mon.avg f max f min Anomaly f-f avg Station surface level pressure, hpa Air temperature, C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 202 Total radiation, MJ/m Total ozone content (TO), DU * * Data of TO measurements require quality control and will not be published until it is done.

11 7 A P R I L Mean sea level pressure, hpa (Vostok st.data - pressure at station surface level) Mirny Novolaz Bellings Vostok (f-f avg )/σf Air temperature, C Mirny Novolaz Bellings Vostok (f-f avg )/σf Relative humidity, % Mirny Novolaz Bellings Vostok (f-f avg )/σf Total cloudiness, tenths Mirny Novolaz Bellings Vostok (f-f avg )/σf Precipitation, mm Mirny Novolaz Bellings Vostok f/f avg Mean wind speed, m/s Mirny Novolaz Bellings Vostok (f-f avg )/σf Fig Comparison of monthly averages of meteorological parameters at the stations, April 2002.

12 8 MAY 2002 MIRNY OBSERVATORY Table 1.9 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f May 2002 Relative anomaly f/f avg Sea level pressure, hpa Air temperature, 0 C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 135 Total radiation, MJ/m Total ozone content (TO), DU Isobaric surface, P, hpa Table 1.10 Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) May 2002 Isobaric surface height, H m Temperature, T 0 C Dew point deficit, D 0 C Resulting wind direction, deg Resulting wind speed, m/s Wind stability parameter Number of days without temperature data Number of days without wind data

13 9 Table 1.11 Anomalies of standard isobaric surface heights and temperature May 2002 P, hpa Н-Н avg, m (Н-H avg )/σ Н Т-Т avg, С (Т-Т avg )/σ Т NOVOLAZAREVSKAYA STATION Table 1.12 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f May 2002 Relative anomaly f/f avg Sea level pressure, hpa Air temperature, 0 C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 135 Total radiation, MJ/m Total ozone content (TO), DU * * Data of TO measurements require quality control and will not be published until it is done.

14 10 BELLINGSHAUSEN STATION Table 1.15 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f May 2002 Relative anomaly f/f avg Sea level pressure, hpa Air temperature, 0 C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 158 Total radiation, MJ/m VOSTOK STATION Table 1.16 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f May 2002 Relative anomaly f/f avg Station surface level pressure, hpa Air temperature, 0 C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 202 Total radiation, MJ/m 2 Polar night Total ozone content (TO), DU * * Data of TO measurements require quality control and will not be published until it is done.

15 11 M a y Mean sea level pressure,hpa (Vostok st.data - pressure at station surface level) Mirny Novolaz Bellings Vostok (f-f avg )/σf Air temperature, C Mirny Novolaz Bellings Vostok (f-f avg )/σf Relative humidity, % Mirny Novolaz Bellings Vostok (f-f avg )/σf Total cloudiness, tenths Mirny Novolaz Bellings Vostok (f-f avg )/σf Precipitation, mm Mirny Novolaz Bellings Vostok f/f avg Mean wind speed, m/s Mirny Novolaz Bellings Vostok (f-f avg )/σf Fig Comparison of monthly averages of meteorological parameters at the stations, May 2002.

16 12 JUNE 2002 MIRNY OBSERVATORY Table 1.17 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f June 2002 Relative anomaly f/f avg Sea level pressure, hpa Air temperature, 0 C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 158 Total radiation, MJ/m Total ozone content (TO), DU No observa tions were done Isobaric surface, P, hpa Table 1.18 Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) June 2002 Isobaric surface height, H m Temperature, T 0 C Dew point deficit, D 0 C Resulting wind direction, deg Resulting wind speed, m/s Wind stability parameter Number of days without temperature data Number of days without wind data

17 13 Anomalies of standard isobaric surface heights and temperature Table 1.19 June 2002 P, hpa Н-Н avg, m (Н-H avg )/σ Н Т-Т avg, С (Т-Т avg )/σ Т NOVOLAZAREVSKAYA STATION Table 1.20 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f June 2002 Relative anomaly f/f avg Sea level pressure, hpa Air temperature, 0 C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 135 Total radiation, MJ/m 2 Total ozone content (TO), DU Polar night Polar night

18 14 Table 1.21 Results of aerological atmospheric sounding (from CLIMAT-TEMP messages) June 2002 Isobaric surface, P, hpa Isobaric surface height, H m Temperature, T 0 C Dew point deficit, D 0 C Resulting wind direction, deg Resulting 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 1.22 June 2002 P, hpa Н-Н avg, m (Н-H avg )/σ Н Т-Т avg, С (Т-Т avg )/σ Т

19 15 BELLINGSHAUSEN STATION Table 1.23 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f June 2002 Relative anomaly f/f avg Sea level pressure, hpa Air temperature, 0 C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 202 Total radiation, MJ/m VOSTOK STATION Table 1.24 Monthly averages of meteorological parameters (f) and their deviations from multiyear averages (f avg ) Parameter f mon.avg f max f min Anomaly f-f avg Normalized anomaly (f-f avg )/σ f June 2002 Relative anomaly f/f avg Station surface level pressure, hpa Air temperature, 0 C Relative humidity, % Total cloudiness (sky coverage), tenths Lower cloudiness(sky coverage),tenths Precipitation, mm Mean wind speed, m/s Prevailing wind direction, deg 270 Total radiation, MJ/m 2 Total ozone content (TO), DU Polar night Polar night

20 16 J u n e Mean sea level pressure, hpa (Vostok st.data - pressure at station surface level) Mirny Novolaz Bellings Vostok (f-f avg )/σf Air temperature, C Mirny Novolaz Bellings Vostok (f-f avg )/σf Relative humidity, % Mirny Novolaz Bellings Vostok (f-f avg )/σf Total cloudiness, tenths Mirny Novolaz Bellings Vostok 0 (f-f avg )/σf Precipitation, mm Mirny Novolaz Bellings Vostok f/f avg Mean wind speed, m/s Mirny Novolaz Bellings Vostok (f-f avg )/σf Fig Comparison of monthly averages of meteorological parameters at the stations, June 2002.

21 2. METEOROLOGICAL CONDITIONS IN ANTARCTICA IN APRIL-JUNE In April-June 2002, large heat anomalies were recorded at the Antarctic Novolazarevskaya, Mirny and Vostok stations. At Vostok station, May was the warmest over the entire observation period from The mean monthly temperature here was 9.1 o C (Fig. 2.1). At Mirny in April and at Novolazarevskaya station in May, the temperature anomaly by the rank of warm years was the third and the second, respectively. Only at Bellingshausen station, there was a large cold anomaly in June (the fourth in the rank of cold years). The temperature conditions in April-June on the entire continent are characterized in Fig. 2.1, which presents monthly averages and the absolute and normalized surface temperature anomalies at the Russian and foreign meteorological stations. Actual data contained in /1/ and multiyear averages for the period /2/ were used. In April-June, the tendency observed from the beginning of 2002 for the dominance of extensive heat centers in the territory of Antarctica was preserved. The core of the heat center similar to March was noted in the Polar Plateau area. Thus April 2002 at Amundsen-Scott station was the second by the rank of warm years (from 1957) at the temperature anomaly of +4.7 o C (+1.9σ). At the same time, a center of cold anomaly (-2.8 o C (-1.1σ) persisted above the western territory of the Queen Maud Land in the vicinity of Halley-Bay station. In May, the above zero temperature anomaly was noted above the entire East Antarctica. The heat anomaly in the vicinity of Vostok station comprised +6.7 o C (+2.6σ). In West Antarctica in the area of the Weddell Sea and the Antarctic Peninsula, a cold center was formed. Its core was situated in the area of Rothera-Point station (-3.4 o C (-1.3σ) in the western part of the peninsula. In June, the heat center has become weaker. The most pronounced heat anomalies were observed only at the East Antarctica coast. In the areas of Dumont D Urville, Mirny and Novolazarevskaya stations, the above zero heat anomalies comprised about 1.5σ (Fig. 2.1). The cold center in West Antarctica has slightly intensified and expanded in area towards the Polar Plateau. The cold anomaly at the core of the center in the vicinity of Rothera-Point station comprised -8.1 o C (-2.2σ). An assessment of the long-period mean monthly temperature changes at the Russian stations in these months indicates the statistically significant tendencies only at Bellingshausen station (Table 2.1, Figs ). A temperature increase in May and June at Bellingshausen station from 1968 was 2.34 o C/35 years and 2.4 o C/35years, respectively. Linear trend parameters of the monthly surface air temperature averages Table 2.1 Stations Novolazarevskaya, Mirny, Vostok, Bellingshausen, Parameter IV V VI IV V VI Entire observation period period o C/1 year % P o C/1 year % P o C/1 year % P o C/1 year % P Note: First line is the linear trend coefficient; Second line - dispersion explained by the linear trend; Third line - level of significance (given if it exceeds 90%, 95% or 99 % confidence intervals). During the last decade, a statistically significant linear temperature trend of April and May in East Antarctica is observed only at Mirny station. The atmospheric pressure at the Russian stations was less in April and June and higher in May compared to a multiyear average. The greatest departures from a multiyear average were observed at Mirny and Vostok stations. In April at Mirny station, a negative pressure anomaly was.5 hpa (-1.7σ). In May at Vostok station a large positive pressure anomaly occurred for the second time after 1975 (+9.8 hpa (1.8σ). A statistically significant negative trend is observed in the interannual variations of atmospheric pressure at Mirny station (April-June) and Novolazarevskaya station (April-May) (Figs ). The atmospheric pressure has decreased most of all for the months under consideration during the period at Mirny station (-6.7hPa/46 years, May).

22 18 During the last decade ( ), a statistically significant linear pressure trend is observed only at Novolazarevskaya station. The pressure decrease here comprised -1.1 hpa/10 years. Precipitation in April and May exceeded a multiyear average. Precipitation in April at Mirny, Novolazarevskaya and Vostok station was 1.5-fold greater than a multiyear average and in May at Novolazarevskaya station about 3-fold and at Vostok station about 2-fold greater than a multiyear average. In June the amount of precipitation at all Russian stations was less than a multiyear average. It is noted that the tendency for the decrease of the amount of precipitation fallout prevails for the months under consideration. References: Atlas of the Oceans. The Southern Ocean. RF MD (in press)

23 Fig Surface air temperatures (1) and their absolute (2) and normalized (3) anomalies in April (IV), May (V) and June (VI) 2002 based on data of stationary meteorological stations in the Southern Polar Area.

24 20 Fig Interannual variations of air temperature and atmospheric pressure anomalies at the Russian Antarctic stations. April.

25 21 Fig Interannual variations of air temperature and atmospheric pressure anomalies at the Russian Antarctic stations. May.

26 22 Fig Interannual variations of air temperature and atmospheric pressure anomalies at the Russian Antarctic stations. June.

27 23 3. ATMOSPHERIC PROCESSES ABOVE THE ANTARCTIC IN APRIL-JUNE 2002 The period April-June for the Antarctic in the climatic respect can be considered as the period preceding winter and the beginning of winter. The character of the atmospheric circulation undergoes sharp changes at this. After summer zonality, the meridional processes predominate. In 2002, the modification of the atmospheric macro-processes in the Southern Hemisphere was especially dramatic. There were significant negative anomalies of the zonal circulation form (see Table 3.1). It is noted that the tendency for the decrease of zonality has appeared as early as February-March. Table 3.1 Frequency of occurrence of the atmospheric circulation forms in the Southern Hemisphere and their anomalies in April-June 2002 Month Frequency of occurrence (days) Anomalies (days) Z M a M b Z M a M b April May June As can be seen from the table, the decrease of the frequency of occurrence of zonal circulation was accompanied with the anomalous development of M b form. We remind that the increased activity of M b form is observed from the middle of 2001 and from February 2002, large anomalies in its frequency of occurrence are observed. This is the main peculiarity of the period under consideration, which is also reflected in the formation of mean monthly temperature and pressure. The most active during April-June was the ridge of the Indian Ocean subtropical High typical of M b processes. The subtropical High ridges combined sometimes with the Antarctic High ridges. The cyclones moved more often along the South American, Central Atlantic and Kerguelen meridional trajectories. The stationary depressions were located above the Lazarev, Riiser-Larsen, Cosmonauts, Davis and Mawson Seas. In these areas, centers of significant negative anomalies of mean monthly pressure were formed. Here, due to an intense meridional outflow of warm air masses, centers of large positive anomalies of mean monthly air temperature were observed. Significant temperature anomalies in April and May at the Russian inland station Vostok presented an important indicator testifying to the increased development of meridionality above the Hemisphere (+6.5 o C in May, see Table 1.16 of this Bulletin). In the lower stratosphere, the modification process has been fully completed by April and a developed winter stratospheric vortex was established.

28 24 4. BRIEF REVIEW OF ICE PROCESSESS IN THE SOUTHERN OCEAN FROM DATA OF SATELLITE AND COASTAL OBSERVATIONS AT THE RUSSIAN ANTARCTIC STATIONS IN APRIL-JUNE 2002 An intense expansion of the Antarctic ice belt that began everywhere in March (see review for the 1 st quarter of 2002) has become sharply slower in April-May. Moreover, in these months in the majority of the areas of the Atlantic and the Indian sectors of the Southern Ocean, the periods with duration of not less than two 10-day periods characterized by an absolute stabilization of the position of the external northern ice edge were observed by turns. As a result, the ice extent in these sectors in May was in general much less than a multiyear average (Fig. 4.1 and Table 4.1). At this background, zones of the active ice export northward in the areas of o W, o W and 10 o E and 85 o E were especially clear. In particular, in spite of the extremely southern location of the Atlantic massif in summer of 2002, the increased autumn advection along the Antarctic Peninsula has determined in the second half of May the ice export from the Weddell Sea reaching Bransfield Strait. A direct result of this was the beginning of stable ice formation in the vicinity of Bellingshausen station on earlier dates usual for the period prior to 1996 (Table 4.2) unlike the last 6 years with a weaker development of ice processes due to warm winters. In June, there was a typical of the Antarctic repeated jump-like increase of the ice belt dimensions. Especially impressive was fantastically rapid young ice coverage of the so-called Weddell Polynya area between o S and 10 o W o E. In conclusion, one should note a decreased intensity of the growth of last year landfast ice that has been preserved in the area of Mirny Observatory (Table 4.3) due to its initially high thermal isolating properties compared to ordinary ice. Table 4.1 Latitudinal location of the external northern drifting ice edge in the Southern Ocean based on satellite data of Novolazarevskaya and Mirny stations in May 2002 Meridians Actual Multiyear average 60º W º W º W º W º W º W º º E º E º E º E º E º E º E º E º E º E º E º E º E º E

29 25 Table 4.2 Dates of onset of main ice phases in the areas of Russian Antarctic stations in the first half of 2002 Station (water area) Landfast ice Ice formation Freeze-up formation First Stable First Stable First Final Mirny (roadstead) Actual Multiyear average Bellingshausen (Ardley Bay) Actual Multiyear average NO NO NO Note: NO phenomenon not observed (has not yet occurred) Average residual (last year) landfast ice thickness (cm) and snow depth on landfast ice (cm) in the Mirny Observatory area from data of profile measurements in the first half of 2002 Table 4.3 Мonths I II III IV V VI Actual Ice Multiyear average Snow

30 26 Fig.4.1. Actual and mean multiyear position of the external northern drifting ice edge in the Southern Ocean in May Symbols: actual; norm (multiyear average).

31 27 5. RESULTS OF TOTAL OZONE MEASUREMENTS AT MIRNY STATION IN THE SECOND QUARTER OF 2002 Regular observations of the total ozone (TO) in the second quarter of 2002 were continued only at Mirny station and were completed due to the low Sun s height on May 13. The monthly TO averages in April-May (273 Dobson units in April and 254 Dobson units in May) were slightly lower than in the previous year. However, in April and May (see Fig. 5.1) quite significant ozone oscillations were observed. This can be probably attributed to the anomalously sharp modification of the zonal atmospheric circulation typical of the summer to the meridional one with an explicit dominance during the period under consideration of the meridional processes that were accompanied with the export of air masses from temperate latitudes. The least TO value of 210 Dobson units was recorded on May Total ozone (DU) /4 11/4 21/4 1/5 11/5 Date Fig Daily total ozone averages at Mirny station in the second quarter of 2002.

32 28 6. GEOPHYSICAL OBSERVATIONS AT RUSSIAN ANTARCTIC STATIONS IN APRIL-JUNE 2002 MIRNY OBSERVATORY Mean monthly absolute geomagnetic field values April May June Declination 86º45.9 W 86º51.4 W 86º57.7 W Horizontal component нт нт нт Vertical component 7496 нт 7496 нт 7546 нт Mirny, April А max, db Mirny, May А max, db Mirny, June А max, db Fig Maximum daily space radio-emission absorption at the 32 MHz frequency from riometer observations in Mirny Observatory.

33 29 Mirny, April 2002 f0f2, MHz UT 12UT Mirny, May 2002 f0f2, MHz UT 12UT Mirny, June 2002 f0f2, MHz UT 12UT Fig Daily variations of critical frequencies of the F2 (f0f2) layer in Mirny Observatory.

34 30 VOSTOK STATION Mean monthly absolute geomagnetic field values April May June Declination 121º04.01 W 121º03.77 W 121º05.91 W Horizontal component nt nt nt Vertical component 8148 nt 8143 nt 8129 nt Vostok, April Аmax, db Vostok, May Аmax, db Vostok, June Аmax, db Fig Maximum daily space radio-emission absorption at the 32 MHz frequency from riometer observations in Vostok Station.

35 31 Vostok, April f0f2, MHz UT 12UT Vostok, May f0f2, MHz UT 12UT Vostok, June f0f2, MHz UT 12UT Fig Daily variations of critical frequencies of the F2 (f0f2) layer in Mirny Observatory.

36 32 UT UT DATE Vostok April, 2002 PC INDEX Fig. 6.5.

37 33 DATE UT UT May, 2002 Vostok PC INDEX Fig. 6.6.

38 34 UT UT DATE Vostok June, 2002 PC INDEX Fig. 6.7.

39 35 Review of the state of the geomagnetic field and ionosphere above the Antarctic in the second quarter of 2002 The geophysical observations were conducted at Novolazarevskaya 1 (magnetic), Vostok and Mirny (magnetic, vertical sounding of the ionosphere and riometer observations) stations. The state of the ionosphere is characterized by the behavior of the critical frequencies of the F2 (f0f2) layer. The daily variations of f0f2 correspond to a multiyear average. The clearly pronounced daily variations in early April are replaced by poorly pronounced daily variations during the rest of the period, which is related to the onset of polar night and the change in the ionosphere illumination.

40 36 7. SPATIAL-TEMPORAL VARIABILITY OF THE HYDROCHEMICAL SEA WATER PARAMETERS IN THE COASTAL ZONE OF ARDLEY BAY (BELLINGSHAUSEN STATION AREA) IN THE SUMMER PERIOD Fomichev N.I. The ecological studies undertaken by RAE personnel at Bellingshausen station in the summer seasons aimed to investigate the physical-chemical characteristics of the water mass in the coastal part of Ardley Bay and its variability in the summertime. This area is the place of discharge of sewage water without any preliminary treatment from the Russian Bellingshausen Base located in direct proximity and from the Chilean Frei Base. In terms of hydrology this area is interesting as Ardley Bay presents a zone of mixing of sea and river water (Stantsionny Stream). No direct measurements of the total freshwater volume (melting of snow, glaciers and ice and fallout of liquid precipitation) discharged to the area of Ardley and Maxwell Bays were made. The indirect data collected during the oceanographic studies indicate a sufficiently large freshwater runoff volume. Thus, in Maxwell Bay with its integral component Ardley Bay there is a halocline in the 5-m depth in the summertime. Typically, a lower temperature corresponds to the highest salinity. Such vertical stratification forms due to the runoff of warmer and fresh land waters. For example, in January 1989 /1/, the temperature in the central part of Maxwell Bay was +0.1 o C at the salinity of In the coastal area of Nelson Island, the salinity comprises 34.2 at a temperature of +0.9 o C. A typical feature of the study area is the anomalously high tidal sea level oscillations as compared to Hope Bay (63 o 24 S, 56 o 50 W) and Port Foster (62 o 58 S, 60 o 34 W). According to /2/, the tide in Ardley Bay is irregular and semi-diurnal. The tropical tide comprises 2 m and the average tide amplitude is equal to 103 cm whereas the syzygy and neap tides have amplitudes of 146 cm and 42 cm, respectively. At a strong wind (up to 30 m/s), no significant surge sea level oscillations are observed. In the author s opinion /2/, this is due to a transit water transport across Fildes Strait between King George Island (Waterloo) and Nelson Island (Leipzig). In order to investigate the spatial-temporal variability of the physical-chemical water mass parameters in Ardley Bay in summer, the hydrological transects were made during the season. The measurement methods and equipment were described before /3/. In our opinion, the shortcomings of the study also include the fact that due to the absence of the corresponding measurement instruments there were no observations to investigate the hydrodynamic processes that produce a significant influence on the character and intensity of hydrochemical, hydrobiological and physical-chemical processes as well as on self-purification, productivity, etc. That is why the condition that any serious decision in the area of protection and rational use of water resources should be based on the experimental study of the hydrodynamic conditions of a specific water body /4/ was not fulfilled. The graphical presentation of all diverse forms of the spatial-temporal variability of the measured parameters of the coastal water mass does not appear to be possible. Therefore, it is important to present the generalized figures and some statistical characteristics of the coastal water mass. One can hope that these preliminary results will serve as a primary basis for further planning and conduct of any special (in terms of a narrow profile and the choice of the study of the specific geo-chemical system: river-sea, water mass, ocean-atmosphere and water-bottom sediments) scientific experiments that are necessary in this area due to a constantly increasing anthropogenic load. A distinct difference of the spatial-temporal variability of sea water parameters at the transects is determined in our opinion by the influence of the wind, air temperature, discharge of melt water and tidal sea level oscillations. The response to the impact of all these different scale processes (integral value) can be characterized by the RMS deviations of the measured sea water parameters obtained from the material of two transects in Ardley Bay (Figs. 7.1 and 7.2).

41 A C B D E Fig Isolines of standard σ deviations (A ph), (B Eh, mb), (C T o C), (D S ), (E O 2, mg. l -1 ). Transect No. 1. Observation period - November 17, 2000 January 26, Observation period for oxygen - November 17, 2000 January 8, A C B -20 D E Fig Isolines of standard σ deviations (A ph), (B Eh, mb), (C T o C), (D S ), (E O 2, mg. l -1 ). Observation period - November 17, 2000 January 26, Transect No. 2. Observation period for oxygen - November 17, 2000 January 8, As can be seen in Figs. 7.1 and 7.2 and in Table 7.1, the ph, S and T o C parameters have a variability maximum in the upper layer. This is due here to the influence of the hydrometeorological conditions on the quasiuniform upper layer. According to our observations, a more freshened upper layer is clearly identified in Figs. 7.1 and 7.2 by the maximum temperature and salinity variability and auto-correlated functions of S and T o C (Fig. 7.4). The temporal variability (Fig. 7.3) characterizes a periodic disturbance of the salinity-temperature gradient of the upper layer due to wave mixing.

42 st st T S ph st st Fig Temporal variability of T o C, S and ph at stations in Ardley Bay in summer from November 17, 2000 to January 26, By X-axis No. of measurements and by Y-axis depth of the place in meters In the coastal zone of Ardley Bay at onshore winds, water roiling occurs due to shallow water and frequent mixing because of sea wave. Interstital water rich in nutrients is displaced at this and the effective surface area participating in the process of bottom sediment diffusion increases. The sea water chemistry changes by means of Redox reactions and nutrients income from bottom sediments where their concentration is much greater than in ambient sea water. Simultaneously, equalizing of water temperature by vertical and carbon dioxide concentration between the ocean and the atmosphere occurs. The offshore wind contributes to the development of coastal upwelling due to which warm coastal water is replaced by colder intermediate water. In the absence of wind, which is extremely rare in the given area, the state of the water mass and the ocean-atmosphere systems rapidly stabilizes. A longer process of the equilibrium reconstruction occurs in the water-bottom sediment system. According to /5/, the equilibrium between the different water medium forms is established for 10 days. Thus, considering that according to the hydrometeorological conditions of the given area, the coastal water mass cannot stay for such a long time in the state of rest, it can be said that a periodic partial washout of nutrients and other substances from the coastal zone occurs due to ambient sea water substitution at tidal oscillation and coastal upwelling. The advective processes influence the variability of the oxygen regime in addition to the bio-chemical processes. The salinity field variability of intermediate water (below the halocline) in the coastal band is also determined by sea water advection. The dynamics of these processes can be traced in Figs. 7.5 and 7.6. The influence of bottom topography on the intermediate water mass rising to the surface (Fig. 7.5) and its transformation (Fig. 7.6) is evident. The iso-correlates (Figs. 7.5 and 7.6) were plotted according to the methods set forth in /6/.

43 39 st.1 st.2 st.3 st.1 st.2 st.3 st.1 st.2 st A B C -30 Fig Iso-correlates of ph (A), temperature (B) and salinity (C). Transect No. 1 (stations 1, 2 and 3) st.4 st.5 st.6 st.7 st.4 st.5 st.6 st A B Fig Iso-correlates of salinity (A) and temperature (B). Transect No. 2 (stations 4, 5, 6 and 7) -20 It is noted that the bottom relief at transect No. 2 contributes to a better mixing of the entire sea water column, which influences the dynamics of the spatial variability of ph. The correlation of the ph observation series at standard horizons is practically everywhere equal to 1 indicating a high linear relation of the direction of the processes over the entire transect. This can also be seen from the auto-correlating functions at each horizon (station 7, Fig. 7.6). 1m 5m 10m 15m 20m S 27m 1m 5m 10m 15m 20m 22m 1m 5m 10m 15m 20m T 27m 1m 5m 10m 15m 20m 22m 1m 5m 10m 15m 20m ph 27m 1m 5m 10m 15m 20m 22m St.3 St.7 Fig Self-correlating functions (R(x,τ)), S, T o C and ph. Ardley Bay, station 7 and station season The normalized auto-correlating functions testify to an ambiguous influence of the synoptic-scale processes on the vertical sea water structure at the points at different transects. This can indicate that in Ardley Bay, the shore and bottom relief contours play a significant role in the formation of the hydrological regime. Due to this, a non-uniform anisotropic spatial-temporal statistic structure of the ph field and in the upper (surface) layer - of the temperature field is created. The salinity as a more conservative sea water parameter has almost one and the same form of the correlation functions, that is why in the first approximation one can suggest that the salinity field by transects is isotropic.