Scientific Issues of AMY08 Atmosphere- O cean- L and I nteraction -Part I

1. Scientific Issues of AMY08Atmosphere-Ocean-Land Interaction-Part I Guoxiong WU 3 September, 2007 Bali, Indonesia

2. Outlines 1. Science Significance 2. Energy and water cycle 3. Land-air-sea interaction 4. Science Issues

3. Monsoon and the Year of Tropical Convection-WCRP JSC-XXVIII Guoxiong WU, Richard Lawford and Howard Cattle 27 March, 2007 Zanzibar

4. 1. Science Significance Monsoon- one of the central components of the climate system: • influence the global climate system • has distinct regional characteristics Monsoonal circulations dominate south and east Asia and are also significant in Africa and the Americas.

5. Major monsoons systems of the world EAM AMY08 NAMS IM WAM AUM SAMS NDVI image for 21-31 August 2000, from Pathfinder AVHRR NDVI surface vegetation

6. CLIVAR and GEWEX coordinate studies in the three primary monsoon regions • Africa: AMMA ‘s focus on West African Monsoon (WAM) and its variability with an emphasis on daily-inter-annual timescales; • Asia-Australia : directed at understanding the processes responsible for the onset, evolution and termination of the monsoon • Americas : emphasizes the determination of the sources and limits of predictability of warm season precipitation.

8. Monsoons • Presentations were made by G. Wu (assisted by R. Lawford and H. Cattle), Yasunari and J. Shukla. • Main points of discussion are as follows: • There is a large number of national and multi-national monsoon programmes and activities. The idea of holding an International Monsoon Year (as component of an International Monsoon Study 2007-2011) created interest and the support of the JSC….…. • It was recommended that a short term task team (one year) be appointed (Chairs B. Wang and J. Matsumoto) to develop a 5 year Implementation Plan,building on and integrating the existing plans for Year of Tropical Convection (YOTC) (joint with THORPEX), the Asian Monsoon Yearand to ensure the monsoon data sets are exchanged and appropriately archived and that the appropriate modelling studies are pursued…. • The consensus was that the crosscut should be deeply rooted in CLIVAR and GEWEX projects. • CLIVAR and GEWEX should organise further pan WCRP workshops building on the progress of the first pan WCRP Monsoon Workshop. • The JSC group responsible for further oversight of Monsoons is G. Wu (Chair), J. Slingo, T. Yasunari, C. Vera, L. A.. Ogallo and J. Shukla.

9. Decision: • Endorse the WCRP crosscutting Monsoon Initiative. The JSC commented that the monsoon crosscut should include all the monsoon groups with a broader perspective, led by CLIVAR and GEWEX with participation of SPARC, CliC and WGNE and several activities outside WCRP (particularly THORPEX). • Request CLIVAR and GEWEX to agree on how it will be supervised and the development of an implementation plan. The proposals for and concepts of an Asian Monsoon Year and an International Year of Tropical Convection should be considered as components of an International Monsoon Study 2007-2011, a 5-year strategy of WCRP monsoon research, which would include issues related to the East African Monsoon, capacity building and application of observations and predictions in monsoon regions for societal benefit. GEWEX and CLIVAR to rationalise the number of monsoon committees.

10. 2. Energy and water cycle “Asian Monsoon Year (AMY’08)”: The “Asian Monsoon Year (AMY08)” (2008-2009) initiative is a coordinated observation and modeling effort on understanding the aerosol-cloud/radiation--hydrology cycle-circulation interaction and ocean-land-atmosphere interaction of the Asian monsoon system, and on improving monsoon prediction.

11. 20 44 24 6

12. Global mean Downward net Radiation Longwave radiation Sensible heat release 10 1 5 4 Latent heat release Energy Budget at the surface

14. MAY 160.6 PRCP 136.1 98.6 149.4 266.4 EVAP 46.0 JUNE 204.0 JUN PRCP 165.4 PRCP 165.4 385.9 63.8 385.9 63.8 334.7 EVAP 97.3 Water cycle over SCS May-Jun. (105- 120E, 0- 20N ); 1.0106 kg s-1.

15. JULY 219.8 PRCP 163.6 335.1 28.1 336.6 EVAP 46.0 AUG. 124.3 PRCP 165.4 PRCP 170.3 63.8 397.6 165.2 372.6 EVAP 128.6 Water cycle over SCS Jul-Aug. (105- 120E, 0- 20N ); 1.0106 kg s-1.

16. Evaporation and rainfall Vq Vq Po Pi E Total PrecipitationP= Po+ Pi Recyc. Prec. RatioR=Pi/P

17. 3. Land-air-sea interaction “Asian Monsoon Year (AMY’08)”: The “Asian Monsoon Year (AMY08)” (2008-2009) initiative is a coordinated observation and modeling effort on understanding the aerosol-cloud/radiation--hydrology cycle-circulation interaction and ocean-land-atmosphere interaction of the Asian monsoon system, and on improving monsoon prediction.

18. a L S C D b 150 50 180 100 30 -220 -240 L S C D c L S C D Kd-1 Summertime quadruplet heating LOSECOD

19. Circulation exited by LOSECOD

20. PNAA AAEA a PNAA AAEA b c d Subtropical LOSECOD Heating and anticyclone

21. ASAf IAU PSAm a ASAf IAU PSAm b c d Subtropical LOSECOD Heating and anticyclone

22. Sub. High Rain Western PacificSubtropical anticyclone

23. Western Pacific SSTa and Typhone tract 台风路径的合成差分布（暖年－冷年，7－10月）

24. Indian Ocean evaporation Ocean thermal state 索马里急流 海 面 水 汽 蒸 发 Transfer of watervaper

25. 索马里急流 季风低压 D D Monsoon=>ocean current=>SST -- QBO, MISO 马斯克林高压

26. 图5.24a

27. 图5.27a

30. During northern summer, the oceanic TCZ migrates seasonally over Indian sub-continent and leads to formation of a semi-permanent system known as monsoon trough (CTCZ) by second fortnight of July. The monsoon trough is controlled by two centers of lows Seasonal low At western end over Pakistan and adjoining area Transient disturbances Form over the Head Bay region and move across the trough.

31. Modulation of the Tibetan Plateau frequency distribution of SAH center (NCEP/NCAR pentad mean)

32. The composed 100hPa streamlines and vectors in Jul-Aug

33. the composed surface temperature anomalies

34. composed precipitation for Tibetan High in Jul-Aug (mm/5day)

35. Coupling of air-sea interaction between tropical Pacific and Indian Ocean

37. 赤道太平洋-印度洋海气相互作用的耦合示意图赤道太平洋-印度洋海气相互作用的耦合示意图 太平洋 Atmos circulation Atmos circulation Warm water upwelling upweling Pacific Ocean Indian Ocean Affect: interannual variability and MISO=>Active and break of monsoon

38. Our shortcomings in tropical convection severely limit the representation of key physics in weather & climate models • Diurnal cycle - strongest “forced” signal in the climate system. • Synoptic waves and easterly waves, including development & evolution of hurricanes and Tropical cyclones • Madden-Julian Oscillation (MJO) and other large-scale convectively-coupled waves • monsoonvariability, including onset and break activity. • Tropical mean state, including ITCZ and distributions of rainfall over oceans & continents Winter 2005-6 Kelvin Waves Rossby Waves MJOs Dominant Convectively-Coupled Tropical Waves Projected onto OLR Anomalies. Wheeler and Weickmann, 2001

39. The monsoon moisture flux WP Flow 台风源区 SAM EAM Typhoons invade AM Three monsoon systems interact

40. Sudden flood Persistent anomaly

41. 4. Science Issues The regional perspective strengthening coordination of Asian-Australian monsoon research: • The air-sea interaction over Indian Ocean and its impacts on Asian monsoon variability (MISO, seasonal and interannual); • Land-sea thermal contrast, diurnal cycle and CTCZ/OTCZ; • Modulation of the TP energy and water cycle on the air-sea interaction over N Indian Ocean; • Air-sea interaction over Western Pacific and its impacts on subtropical anticyclone; • The impacts on Asian monsoon of the air-sea coupling process between tropical Pacific and Indian Ocean; • Water cycle and its variation over the Asian monsoon areas

42. Thank You！