1 summer precipitation anomaly over the southern qinghai plateau and related regions of atmospheric...
TRANSCRIPT
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Summer precipitation anomaly over the Southern Qinghai Plateau and related regions of
atmospheric water vapor transport
REN Yu1,2 ZHANG Xue-qin1 TAO Jie (Reporter)1,2 LI Sheng-chen3
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
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Outline
• Introduction
• Data & Method
• Results
• Conclusion
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Outline
• Introduction
• Data & Method
• Results
• Conclusion
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89° E 90° E 91° E 92° E 93° E 94° E 95° E 96° E 97° E 98° E 99° E 100° E 101° E 102° E 103° E
32° N
33° N
34° N
35° N
36° N
Q inghai
T ibet
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)
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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
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Outline
• Introduction
• Data & Method
• Results
• Conclusion
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Data & Method
89° E 90° E 91° E 92° E 93° E 94° E 95° E 96° E 97° E 98° E 99° E 100° E 101° E 102° E 103° E
32° N
33° N
34° N
35° N
36° N
Yellow R iverYangtze R iver
Langcang R iver
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
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Data & Method
2.5o×2.5ogrid data of surface pressure, specific humidity, U-wind & V-wind from NCEP/NCAR Reanalysis (1961-2004)
60 70 80 90 100 110 120 130 140 150
10
20
30
40
50
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Vertically integrated water vapor flux vector( ), and its component , are calculated according to [Li, 1999]
Data & Method
Q
Q QPrecipitation 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
Q Q
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Outline
• Introduction
• Data & Method
• Results
• Conclusion
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Results: The distribution of mean summer precipitation
Decrease from the southeast to the northwest
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Results: The three modes of summer precipitation over SQP
19611965 1970 1975 1980 1985 1990 1995 20002004-2
-1.5
-1
-0.5
0
0.5
1
1.5
2
2.5
Year
Tim
e c
oeff
icie
nt
34.4%
•Spatial homogeneous•Anomalies decrease from the southeast to the northwest
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Opposite precipitation anomaly at the eastHuangnan TAP to the south Yushu TAP
Results: The three modes of summer precipitation over SQP
19611965 1970 1975 1980 1985 1990 1995 20002004-2
-1.5
-1
-0.5
0
0.5
1
1.5
2
Year
Tim
e c
oeff
icie
nt
22.6%
TAP: Tibetan Autonomous Prefecture
1419611965 1970 1975 1980 1985 1990 1995 20002004-3
-2
-1
0
1
2
3
Year
Tim
e c
oeff
icie
nt
Results: The three modes of summer precipitation over SQP
9.9%
Opposite anomaly over the south Guoluo TAPto the northern SQP
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Results: Water vapor transport
Strong northeastward moisture transport over South China
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Results: Water vapor transport
Strong water vapor transport from the Arab Sea and the Bay ofBengal, the central South China Sea and the West Pacific Ocean
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Results: related regions for mode I
34.4%
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Results: Related water vapor transport regions
Spring Q Spring Q
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
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Results: Related water vapor transport regions
Summer Q Summer Q
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
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22.6%
Results: related regions for mode II
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Results: Related water vapor transport regions
Spring Q Spring Q
Not well correlated
Mode II
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Results: Related water vapor transport regions
Summer Q Summer Q
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
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9.9%
Results: related regions for mode III
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Results: Related water vapor transport regions
Spring Q Spring Q
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.
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Results: Related water vapor transport regions
Summer Q Summer Q
Mode III
The most significant correlated region is found in central Mongolia People’s Republic
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Outline
• Introduction
• Data & Method
• Results
• Conclusion
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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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