The Linkage between the Eastern Pacific Teleconnection Pattern and Convective Heating over the Tropical Western Pacific

• Published in: Journal of Climate
• Main Authors: Tan, Benkui, Yuan, Jiacan, Dai, Ying, Feldstein, Steven B., Lee, Sukyoung
• Other Authors: Tan, BK (reprint author), Peking Univ, Sch Phys, Dept Atmospher & Ocean Sci, Yiheyuan Rd 5, Beijing 100871, Peoples R China., Peking Univ, Sch Phys, Dept Atmospher & Ocean Sci, Beijing 100871, Peoples R China., Penn State Univ, Dept Meteorol, University Pk, PA 16802 USA., Seoul Natl Univ, Sch Earth & Environm Sci, Seoul, South Korea., Peking Univ, Sch Phys, Dept Atmospher & Ocean Sci, Yiheyuan Rd 5, Beijing 100871, Peoples R China.
• Format: Journal/Newspaper
• Language: English
• Published: JOURNAL OF CLIMATE 2015
• Subjects: NORTHERN-HEMISPHERE WINTER; MADDEN-JULIAN OSCILLATION; ATMOSPHERIC CIRCULATION; WAVE-PROPAGATION; STORM TRACKS; VARIABILITY; FLOW; CONTINUUM; IMPACT; JET; Gulf of Alaska; Indian; Pacific; Alaska; Siberia
• Online Access: https://hdl.handle.net/20.500.11897/418736; https://doi.org/10.1175/JCLI-D-14-00568.1

The eastern Pacific (EP) pattern is a recently detected atmospheric teleconnection pattern that frequently occurs during late winter. Through analysis of daily ERA-Interim data and outgoing longwave radiation data for the period of 1979-2011, it is shown here that the formation of the EP is preceded by an anomalous tropical convection dipole, with one extremum located over the eastern Indian Ocean-Maritime Continent and the other over the central Pacific. This is followed by the excitation of two quasi-stationary Rossby wave trains. Departing from the subtropics, north of the region of anomalous convection, one Rossby wave train propagates eastward along the East Asian jet from southern China toward the eastern Pacific. The second wave train propagates northward from east of Japan toward eastern Siberia and then turns southeastward to the Gulf of Alaska. Both wave trains are associated with wave activity flux convergence where the EP pattern develops. The results from an examination of the E vector suggest that the EP undergoes further growth with the aid of positive feedback from high-frequency transient eddies. The frequency of occurrence of the dipole convection anomaly increases significantly from early to late winter, a finding that suggests that it is the seasonal change in the convection anomaly that accounts for the EP being more dominant in late winter. Chinese NSF [41130962, 41375060]; China Postdoctoral Science Foundation [2013M540014]; National Science Foundation [AGS-1139970, AGS-1036858, AGS-1401220]; National Oceanic and Atmospheric Administration Grant [NA14OAR4310190] SCI(E) EI ARTICLE [e-mail] 14 5783-5794 28