1. 1 Summer precipitation anomaly over the Southern Qinghai Plateau and related regions of atmospheric water vapor transport REN Yu 1,2 ZHANG Xue-qin 1 TAO Jie (Reporter) 1,2 LI Sheng-chen 3 1. Institute of geopraphical sciences and natural resources research, Beijing, China 2. Graduate university of Chinese Academy of Sciences, Beijing, China 3. Qinghai Meteorological Administration, Xining, China

2. 2 Outline Introduction Data & Method Results Conclusion

3. 3 Outline Introduction Data & Method Results Conclusion

4. 4 Great threat Introduction Stabilization of water resources Varied mountainous topography Elevation about 4,400m.a.s.l Three Rivers Source (the Yangtze River, Yellow River, Lancang River)

5. 5 Introduction Research points: 1.Identify the main modes of spatial distribution of precipitation anomaly over SQP (Southern Qinghai Plateau) 2.The correlated regions of atmospheric water vapor transport

6. 6 Outline Introduction Data & Method Results Conclusion

7. 7 Data & Method Summer (JJA) precipitation data of 19 surface meteorological stations from 1961-2004, supplied by Qinghai Climate Center Summer holds the most part of the annual precipitation over SQP

8. 8 Data & Method 2.5 o ×2.5 o grid data of surface pressure, specific humidity, U- wind & V-wind from NCEP/NCAR Reanalysis (1961-2004)

9. 9 Vertically integrated water vapor flux vector( ), and its component, are calculated according to [Li, 1999] Data & Method Precipitation anomaly modes and time coefficient (TC) Series (by EOF) Pearson correlation between the TC series and, of both spring (MAM) and summer (JJA) LI, W. P. Moisture Flux and Water Balance over the South China Sea during Late Boreal Spring and Summer, Theoretical and Applied Climatology, 1999: 64, p179-187. Related regions of water vapor transport

10. 10 Outline Introduction Data & Method Results Conclusion

11. 11 Results: The distribution of mean summer precipitation Decrease from the southeast to the northwest

12. 12 Results: The three modes of summer precipitation over SQP 34.4% Spatial homogeneous Anomalies decrease from the southeast to the northwest

13. 13 Opposite precipitation anomaly at the east Huangnan TAP to the south Yushu TAP Results: The three modes of summer precipitation over SQP 22.6% TAP: Tibetan Autonomous Prefecture

14. 14 Results: The three modes of summer precipitation over SQP 9.9% Opposite anomaly over the south Guoluo TAP to the northern SQP

15. 15 Results: Water vapor transport Strong northeastward moisture transport over South China

16. 16 Results: Water vapor transport Strong water vapor transport from the Arab Sea and the Bay of Bengal, the central South China Sea and the West Pacific Ocean

17. 17 Results: related regions for mode I 34.4%

18. 18 Results: Related water vapor transport regions Spring The most significant correlated region is the central South China Sea (When the northward water vapor transport is stronger, the SQP experiences a rainy summer) Mode I

19. 19 Results: Related water vapor transport regions Summer The most significant correlated region is the West Siberia (When the eastward water vapor transport is stronger, the SQP suffers less precipitation in summer) Mode I

20. 20 22.6% Results: related regions for mode II

21. 21 Results: Related water vapor transport regions Spring Not well correlated Mode II

22. 22 Results: Related water vapor transport regions Summer Mode II The most significant correlated region is the eastward water vapor transfer band expanding along the Yangtze River from north Guizhou Province to East China Sea

23. 23 9.9% Results: related regions for mode III

24. 24 Results: Related water vapor transport regions Spring Mode III The eastward water vapor transport over the northwestern part of Mongolia, the southward transport over north Xinjiang Uygur Autonomous Region of China, the northward transport over the sea to the northeast of Pilipino are correlated with TC series III.

25. 25 Results: Related water vapor transport regions Summer Mode III The most significant correlated region is found in central Mongolia People ’ s Republic

26. 26 Outline Introduction Data & Method Results Conclusion

27. 27 Conclusion Mode I: Spatial homogeneous Northward transport, South China Sea, Spring Eastward transport, West Siberia, Summer Mode II: Opposite (East Huangnan TAP: South Yushu TAP) Eastward transport band expanding along the Yangtze River from the north Guizhou province to East China Sea, Summer Mode III: Opposite (South Guoluo TAP: Northern part of SQP Northward water vapor transport over Mongolia, Summer

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