Recent cooling trend over northern Japan in August in relation to the weakening of the Tibetan high
Recent cooling trend over northern Japan in August in relation to the weakening of the Tibetan high
复制标题
与青藏高原高压减弱有关的日本北部8月近期降温趋势
DOI：
10.2480/agrmet.65.2.1
复制
发表时间：
2009
影响因子：
1.3
通讯作者：
S. Yamakawa
中科院分区：
文献类型：
--
作者：
Y. Nagano;H. Kato;S. Yamakawa
本文研究了8月100 hPa青藏高压在东亚活动的年际变化。此外，本研究统计分析了青藏高压的年际变化对日本北方天气的影响。日本北方100 hPa高度场在1991年以前一直为正距平，但1992年以后经过不连续的变化，一直为负距平。自1992年以来，日本北方上空的青藏高压明显减弱。利用气压模式分析日本周围出现的锋面频率，发现自1992年以来，平均频率增加了约2.5倍，这在统计上是显着的。另外，北海道的气温自1992年以来一直呈负距平，当时也出现了不连续的变化。西藏高压的强度与日本周围锋面出现频率的增加和北海道气温的下降有直接关系。本研究还分析了典型年份。在1982年和1990年，当西藏高压很强时，北海道气温很高，日本周围出现了几个锋。而1993年和2002年的青藏高压范围较小，北海道气温较低，日本周边锋出现频率较高。
This study examines interannual changes in the behavior of the August 100 hPa Tibetan high in East Asia. In addition, this study statistically analyzes the influence of interannual changes of the Tibetan high on the weather in northern Japan. A positive anomaly of geopotential height at the 100 hPa was endured before 1991 over northern Japan, but a negative anomaly has continued since 1992 after discontinuous change. The Tibetan high weakened significantly over northern Japan since 1992. Using pressure patterns to analyze the frequency of the front appearing around Japan shows that the mean frequency has increased about 2.5 times since 1992, which is statistically significant. In addition, the temperature in Hokkaido has shown a negative anomaly since 1992, when discontinuous change also occurred. The strength of the Tibetan high is directly related to the increase in the frequency at which the front appears around Japan and the temperature drop in Hokkaido. This study also analyzes typical years. In both 1982 and 1990, when the Tibetan high was strong, temperatures were high in Hokkaido and a few fronts appeared around Japan. In contrast, in 1993 and 2002, the extent of the Tibetan high was smaller, temperatures were lower in Hokkaido, and the appearance frequency of the front around Japan was higher respectively.