Cold surge event observed by radiosonde observation from the research vessel \u201cHakuho-maru\u201d over the Philippine Sea in December 2012

Shin-Ya Ogino,Tomoshige Inoue,Jun Matsumoto,Peiming Wu,Nobuhiko Endo,Miki Hattori,Hisayuki Kubota

doi:10.1186/s40645-017-0163-4

Abstract

The thermal energy transfer from the sea surface to the atmosphere associated with a cold surge event was investigated with observations from radiosondes on the research vessel “Hakuho-maru” over the Philippine Sea in December 2012. These observations were analyzed, and the results were compared with those obtained from observations over the East China Sea in the Air Mass Transformation Experiment in 1974 (AMTEX ‘74). The horizontal advection of cold and dry air associated with the cold surge dominated at heights below 850 hPa. In spite of this strong advection, the local temporal variations in the temperature and moisture were small, because the advection was balanced by the transfer of heat and moisture from the sea surface, which is qualitatively the same behavior as observed during the cold surge event in AMTEX ‘74. The eddy transport of the total heat energy from the sea surface to the atmosphere was estimated at about 410 W/m2, which is about half of the maximum value of 780 W/m2 observed during AMTEX ‘74. This result shows the existence of considerable heat transfer from the sea surface to the atmosphere over the Philippine Sea, which is the downstream region of the cold surge, after it passed through the East China Sea.

Highlights

Cold surges originating from the Siberian High are common during the Asian winter monsoon and can extend as far as the Southeast Asia, including the Philippines and the Indochina Peninsula
We succeeded in observing the air-sea interactions associated with a cold surge event using radiosondes on
The strong horizontal advection of cold and dry air due to the cold surge dominated in the layer below 850 hPa

Summary

Introduction

Cold surges originating from the Siberian High are common during the Asian winter monsoon and can extend as far as the Southeast Asia, including the Philippines and the Indochina Peninsula. Note that the result of the AMTEX ‘74 budget analysis showed the maximum heat and moisture transport from the ocean to the atmosphere near the end of the temperature decrease associated with the cold surge.

Results

Conclusion