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Recent SST, Sea ice, and Snow Cover Monitoring and Diagnosis. YUAN Yuan , ZHOU Bing. Beijing Climate Center, CMA. ( Thanks to Dr. Guo Y J and Dr. Ma L J ). Outline. Recent SST monitoring and diagnosis Possible impacts of negative PDO Sea ice and snow cover monitoring. Monthly SSTA.
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Recent SST, Sea ice, and Snow Cover Monitoring and Diagnosis YUAN Yuan, ZHOU Bing Beijing Climate Center, CMA (Thanks to Dr. Guo Y J and Dr. Ma L J )
Outline Recent SST monitoring and diagnosis Possible impacts of negative PDO Sea ice and snow cover monitoring
Monthly SSTA Dec. 2012 Jan. 2013 Feb. 2013
Atmospheric Circulation Anom. DJF A Red contour: Climatological WPSH Anomaly percentage of rainfall in DJF 2012/13
Physical Mechanism for the Anticyclone Wang et al. 2000, J. Climate, 13: 1517-1536 A A C Warm Cold e.g. Watanabe and Jin, 2002; Xie et al. 2009; Wu et al. 2010; Yuan et al, 2012
SSTA in March 2013 The latest weekly SST departures are: Niño 4 0.0ºC Niño 3.4 0.1ºC Niño 3 0.0ºC Niño 1+2 -0.9ºC (From CPC)
Outline Recent SST monitoring and diagnosis Possible impacts of negative PDO Sea ice and snow cover monitoring
Composite difference of summer rainfall anomaly between positive and negative PDO years Precipitation data: GPCC V6 & CRU TS 3.10.01 Red line: PDO9 Green and black lines: NC9
Composite Difference between positive and negative PDO phases SSTA 850UV 500H
Enhanced EASM More summer rainfall in North China Negative PDO Eastward and northward WPSH
Outline Recent SST monitoring and diagnosis Possible impacts of negative PDO Sea ice and snow cover monitoring
Sea Ice Concentration in NH--DJF Over 40% below normal in the Barents Sea and western Kara Sea The fourth least since 1978
Average Snow Depth in China--DJF Northeast China Northern Xinjiang Tibet Plateau China
Conclusions In DJF 2012/13, SSTA over the equatorial eastern-central Pacific was slightly below normal; PDO persisted in its negative phase; SSTA over the tropical Indian Ocean was significantly above normal, which excited anomalous low-level anticyclone to the east of the Philippines The significant negative PDO would lead to a strong East Asian summer monsoon and a weak WPSH in summer 2013. Therefore, more precipitation tends to occur in North China. In DJF 2012/13, sea ice concentrations were over 40% below normal in Barents Sea and western Kara Sea, while mostly above normal in the sea areas around Antarctica. The area of snow cover was evidently larger than normal in Northeast China, with the average snow depth the deepest since 1973.