Relationship between SSTA in the northwestern Pacific and winter climate anomaly in China

摘要

The relationship between sea surface temperature anomaly (SSTA) in the domain from the northwest of thc Pacific to Chinaseas (NWP-CS) andclimate (precipitation and surface temperature) anomaly in winters over east of Chinese Mainland (ECM) are investigated with composite analysis. The results suggest that (1) SSTA in NWP-CS usually appears as "seesaw" pattern, I.e., sign of SSTA in the northwest of thc Philippines is positive (negative) while in the southeast it is negative (positive), defmed as SSTA "seesaw" positive (negative) pattern. When SSTA "seesaw" positive(negative) pattern appears, the surface temperature in ECM is higher (lower) than the normal winters but thc precipitation anomaly is not distinct; (2) there are two anomalous anticyclones (cyclones) locating in the northwest Pacific and east of the Philippines at 850 hPa level and an anomalous anti-Hadley (Hadley) circulation, which descends (ascends)south of 18°N, ascends (descends) north of 18°N; (3) heat flux anomaly from ocean into atmosphere is weaker (stronger)in the northwest of the Philippines but stronger (weaker) in the southeast of the Philippines than the normal winters, because the weaker (stronger) northerly prevails in thc northwest of the Philippines and stronger (weaker) northeaster in the southeast of the Philippines induced by anomalous anticyclones (cyclones).