摘要
１０年以内的各种气候变化，除正常年变化外，其余各种变化或因周期太短（如正常日变化、天气周期变化），或因气温振幅太小（如年际变化、月、季变化等），对３.２ｍ地温变化幅度的贡献均在０.０５—０.１５℃之间，故消除了正常年变化（取距平后的）３.２ｍ地温场（Ｔ′３２）在相当程度上是３２ｍ以下地热活动的反映，特别是｜Ｔ′３２｜≥０５℃的高（低）温中心，基本上是地下热活动的反映。分析了１９８０年以来逐季的Ｔ′３２图，发现其高值中心的演变颇有规律：从初生到最强阶段中心位置少动，此时Ｔ′３２水平梯度较大，强盛阶段一般与本区地震多发时段相连，在减弱和消失阶段表现为水平梯度变小，中心分裂。一个高温中心一般可维持１—５年。处在强盛阶段及稍后一些的高温中心区，当其尺度达到１０００ｋｍ时（用高温区周围的低温轴线的包围区计算），本身可以“制造多雨系统”，使得高温区多雨；当尺度小于１０００ｋｍ时，一般只能影响已有的天气气候系统。
All of the atmospheric vibrations with the time scale less than 10 years are only a little contribution to the amplitude of soil temperature at depth 3 2 m (about 0 05 0 15 ℃,except the normal annual cycle),due to that of the short period (such as diurnal cycle,natural synoptic period) or the small amplitude of air temperature (such as monthly、seasonal or interannual variation) So that the anomaly field of T 3 2 (T ′ 3 2 ) is almost like a indicator of thermal process in lithosphere, specially the high(low) value regions with the |T ′ 3 2 |≥0 5 ℃ are definitive indicator. After analysing the seasonal mean field of T ′ 3 2 since 1980,it is found that the high value centers of T ′ 3 2 have a regular evolution:the location of high center is almost steady during the initiate stage until the warmest stage,which is also the seisms active stage,hence the horizonal gradient of T ′ 3 2 decreased and the center separated each other during the weakening stage. Whenever the horizontal scale of high temperature region reaches to 1 000 km in the warmest stage,the precipitation system in atmosphere will be aroused over the high temperature region,which will have more rain;if the scale less than 1 000 km,the precipitation system will not be aroused.
出处
《高原气象》
CSCD
北大核心
1994年第2期178-187,共10页
Plateau Meteorology
基金
中科院KY85-10-03课题
国家重大基础研究项目
关键词
地温距平场
地震
汛期预报
降水
s:Soil temperature anomaly field
Seisms
Precipitation anomaly field
Flood season's forecasting.
