关键词: 季节冻土, 退化, 气候变化, 响应, 青海

Abstract:

Based on the mathematical statistic method of correlation analysis, the impact of natural factors of climate and topography upon spatial-temporal distribution of seasonal tjale is analyzed, and the response of tjale to air temperature, precipitation and cloudiness is also simulated. The results show that the topography and climate factor have a significant influence on the distribution and evolution of seasonal tjale in Qinghai, the topographic factors include altitude, longitude, latitude, slope, direction of inclination and so on. Since atmosphere is most active and sensitive compared with the others in the climate system, the climate factor and its change have significant effect on the seasonal tjale, at the same time, in that the tjale's response upon the temperature variation is most sensitive, so it is considered that global warming is the primary factor to cause seasonal tjale degeneration. The variation of local climate effect of the increasing of heat island effect brought by the urbanization in Xining and the decreasing of water effect caused by the descending of water level in Qinghai lake intensify the response of seasonal tjale upon climate change to some extent, the seasonal tjale has an evident time-delay upon the response of the air temperature variation at dekad and month scale, while it is not so significant on the interannual scale. At the same time, the response of surface temperature upon the temperature change is delayed gradually with the depth increasing, it shows : more deeper, the delay effect is more obvious.

Key words: seasonal tjale, degeneration, climate change, response, Qinghai