1978－1979年冬季季風實驗（Winter MONEX）期間重要大氣現象分析

Some Prominent Atmospheric Events in Asia during the Period of Winter MONEX, 1978-79

吳宗堯(Tsung-Yao Wu) ； 王時鼎(Shih-Ting Wang)

《大氣科學》 6卷1期 (1979/05) Pp. 55-65

並列摘要

(1) Polar Outbreaks in the Low Latitudes during the Period of Winter MONEX, 1978-79Among 25 frontal passages over Taiwan during the period of winter MONEX, there were three fronts caused by polar outbreaks. The dates were 10-11 December, 18-19 December and 31 January to 1 February, respectively, and the last one was the strongest among all yet with snow ever recorded at An-Pu station near Taipei. For further study and reference, the surface synoptic charts, the 500mb anomaly charts, and the time cross sections of wind aloft at Ma-Kung, showing the monsoon surges, for these three outbreaks are briefly documented.(2) An Unsteady Easterly Wave in the South China Sea during the Period of Winter MONEXAn unsteady easterly wave occurred in the South China Sea was Observed duing the period of Winter MONEX. It seems that this easterly wave did not belong to the pure tropic origin, but was one existed in the monsoon mixed with trade wind. At the beginning it seems a standing wave of which the forcing factor was crographic in nature. Concerning the whole life cycle of the wave, the successive 850mb charts, time cross section of wind aloft at Pratas Island are prepared for demonstration and further analysis.(3) On the ”Warm Winter” in Taiwan during the Period of MONEX It is noted that the temperature is above normal in Taiwan in winter, 1978-79, and at the same period, the severe cold weather was experienced in Northen America and Europe. After being analysed the synoptic charts, it is found that in this period the blocking phenomena occurred frequently in the western hemisphere, while the zonal flow dominated in Asia region. these pronounced features could be used to tell the difference in weather phenomena happened in both regions of East and West. In addition, we noticed that the unusually strong and persistent upper easterly wind in the stratosphere in the late winter over Taiwan may be considered as an indicator and predictor for the warm winter of the region.