Air-sea heat flux under the weather of winter cyclone in the Northwest Pacific during Western Pacific Jet Stream anomaly

Abstract

The trajectories of the winter cyclone and the thermal field anomaly over the Northwest Pacific Ocean were studied with the atmospheric reanalysis data (from the NCEP/NCAR) and the SST's observational data (from the Met Office Hadley Centre and the National Climatic Data Center of NOAA). The results showed that the thermal field would change as a response to the circulation shift (e.g. meridional motion of the WPJS). When the WPJS leaned to the north, SHF and LHF would be positive (negative) anomaly in the mid-high (low) latitude, while Qs and SST presented negative anomaly in the mid-high latitude. As a result, the dipole-pattern (+ -) of air temperature anomaly moved northward, which made the storm track leaned to the north. In the opposite, the storm track would lean to the south. On the other hand, if most of the cyclones in the whole winter changed the paths, the transport process of the heat flux, the kinetic energy and the vapor would be significantly different. As a result, there is discrepancy in storm-induced SHF anomaly, LHF anomaly, SST anomaly, and Qs anomaly, compared to other years. Finally, we found the storm-induced thermal field anomaly is comparable to the thermal field climate anomaly.