Analysis on spatial-temporal variation of the anomalous warm winter in China and the general circulation features in Northern Hemisphere
Based on the data of the temperature grades in China (1911-1989) ,analysis on spatial-temporal variation of the anomalous warm winter(AWW) in China and the general circulation features in the NorthernHemisphere is made.It is found that the AWW years mainly occur in theperiod of 1940's and last 10 years with different cyclic stages. Especiallyobvious AWW appears in the regions of Northwest China, Changjiang River Basin and South China. During the last 10 years, the AWW probability takes place most frequently in the region of Northeast China and South China, while rather rarely in the region of Southwest China.The years of AWW have significantly increased in the north of China since 1980's, especially in the region of Northeast China. And the general circulation of the Northern Hemisphere is characterized by the westerly belt here, which appears mainly in Wave 3 and by the anomalous field over Asia, which is lower in west and higher in east.