Atmospheric Moisture during Monsoon 2002 ARMEX Phase I

Transcription

1 Atmospheric Moisture during Monsoon 2002 ARMEX Phase I Anu Simon, K. Mohankumar, Aype Thomas and C.K. Rajan Department of Atmospheric Sciences Cochin University of Science and Technology Cochin

2 All India Rainfall (mm) for June to September 2002 (Climatology is plotted) Oct There was a long dry spell from end June to beginning of August 30-M ay 06-Jun 13-Jun 20-Jun 27-Jun 04-Jul 11-Jul 18-Jul 25-Jul 01-Aug 08-Aug 15-Aug 22-Aug 29-Aug 05-Sep 12-Sep 19-Sep 26-Sep

3 Evolution Of OLR field NOAA(10 dayaverages) JUNE to AUGUST 2002

4 In the present study The moisture field of NCMRWF analysis of the 2002 monsoon (ARMEX Phase I) at levels 1000, 850, 700, 600 and 500 hpa is studied and compared with the and ERA reanalysis data sets.

5 A comparison is also made with the moisture field of monsoon 1998, during which the break monsoon spells were short, using the available and ERA reanalysis data sets.

6 All India Rainfall (mm) for June to September 1998 (Climatology is plotted)

7 Average Specific Humidity(g/kg) -NCMWRF for Arabian sea box (10-20N,55-75 E) 01 June to 31 August hPa 700hPa 14 ALL INDIA DAILY RAINFALL (mm) -JUNE TO SEPTE May 06-Jun 13-Jun 20-Jun 27-Jun 04-Jul 11-Jul 18-Jul 25-Jul 01-Aug 08-Aug 15-Aug 22-Aug 29-Aug 05-Sep 600hPa 500hPa

8 Average Specific Humidity(g/kg) NCMWRF for Bay Of Bengal (10-20N, E) 01 June to 31 August hPa 700hPa 600hPa 500hPa

9 Average Specific Humidity(g/kg) for Arabian sea (10-20N,55-75 E) 01 June 31 August hPa 700hPa 600hPa 500hPa

10 Specfic Humdity (g/kg) 600hPa Specfic Humdity (g/kg) 500hPa Jun 8-Jun 15-Jun 22-Jun 29-Jun 6-Jul 13-Jul 20-Jul 27-Jul 3-Aug 10-Aug 17-Aug 24-Aug 1-Jun 8-Jun 15-Jun 22-Jun 29-Jun 6-Jul 13-Jul 20-Jul 27-Jul 3-Aug 10-Aug 17-Aug 24-Aug Specfic Humdity (g/kg) 600hPa Specfic Humdity (g/kg) 500hPa Jun 8-Jun 15-Jun 22-Jun 29-Jun 6-Jul 13-Jul 20-Jul 27-Jul 3-Aug 10-Aug 17-Aug 24-Aug 1-Jun 8-Jun 15-Jun 22-Jun 29-Jun 6-Jul 13-Jul 20-Jul 27-Jul 3-Aug 10-Aug 17-Aug 24-Aug

11 Evolution Of OLR field NOAA(10 dayaverages) JUNE to AUGUST 1998

12 10 day average of Specific Humidity July JUL 1000 hpa NCMRWF NCMRW JUL1000 hpa NCMRW JUL 1000 hpa F F NCMRWF

13 10 day average of Specific Humidity July 2002 NCMRWF 1-10 JUL 700 hpa JUL 700 hpa NCMRWF JUL 700 hpa NCMRWF

14 1-10 JUL 500 hpa 10 day average of Specific Humidity July 2002 NCMRWF JUL 500 hpa NCMRWF JUL 500 hpa NCMRWF

15 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 2002 July at 1000hPa NCMWRF

16 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 2002 July at 700hPa NCMWRF

17 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 2002 July at 600hPa NCMWRF

18 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 2002 July at 500hPa NCMWRF

19 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 2002 August at 1000hPa NCMWRF

20 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 2002 August at 700hPa NCMWRF

21 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 2002 August at 600hPa NCMWRF

22 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 2002 August at 500hPa NCMWRF NCMWRF

23 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 1998 July at 1000hPa

24 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 1998 July at 700hPa

25 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 1998 July at 600hPa

26 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 1998 July at 500hPa

27 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 1998 August at 1000hPa

28 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 1998 August at 700hPa

29 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 1998 August at 600hPa

30 Wind in m/s (vectors) and Specific Humidity in g/kg (shaded) for 1998 August at 500hPa

31 INTEGRATED MOISTURE FLUX (Kgm -1 s -1 ) ( ) for July 2002 NCMRWF Integrated Flux = 1 g P t P 0 Vq dp

32 INTEGRATED MOISTURE FLUX (Kgm -1 s -1 ) ( ) for July 1998

33 DAILY MOISTURE TRANSPORT ACROSS 75 E FROM 10 20N (kg/day) NCMRWF hPa hPa

34 DAILY MOISTURE TRANSPORT ACROSS 75 E FROM 10 20N (kg/day) hPa

35 DAILY MOISTURE TRANSPORT ACROSS 75 E FROM 10 20N (kg/day) hPa

36 Conclusions During the dry July of 2002 (long break) Arabian Sea had very low moisture at levels above 700hPa Dry air over Arabian sea above 700hPa in July 2002 appears to have come from both the south Indian ocean across the equator and also from the dry continental areas to the north In August, the Arabian sea was more moist with the relatively dry air from the south Indian ocean spreading to south of the Indian peninsula.

37 The moisture field of Bay of Bengal doesn't show much variation during July unlike that of the Arabian Sea. A comparison with the moisture at 600 and 500 hpa levels of 1998 (year with short breaks) show that moisture at these levels in July was more than that of It also remained high throughout the season with very little variations The vertically integrated moisture ( hPa) during July 2002 was relatively less than that during 1998

38 Moisture transport at hpa across the west coast of India (10-20N) during July 2002 was very low compared to August 2002 and also of July & August In general at all levels 1000hPa to 500hPa / has less/more moisture than NCMWRF

39 Thank You