摘要
把SMMR监测地表土冻融两参数:37GHz亮温T_(37)及18～37GHz亮温谱梯度SG归纳成单一模式。它已部分容纳土中含水量对SG的影响,所以冻融区分准确率有所提高,降低了含水量变化带来的波动。1983年SMMR在青海高原的水平极化18及37GHz亮温记录与台站5cm深冻融地温实况相比较,确定模式统计形式,并据此监测青藏高原地表土全年冻融动态过程。结果表明,本区地表土的冻融变化随海拔、坡向及纬度等诸要素而变化。
The brightness temperature at 37 GHz (T37) and spectral gradient of brightness temperature between 18 and 37 GHz (SG) are usually used as indictors for monitoring freezing/ thawing condition of terrain soil. This study sums them up as an algorithm. Since the algorithm has partly considered the influence of soil's water content on SG, its accuracy for classification of freezing / thawing condition has some improvement and it partly decreases the accuracy variation caused by the change of water content. The station soil temperature at 5 cm depth in Qinghai Plateau is compared with the records of horizontally polarized brightness temperature at 37 and 18 GHz from SMMR in 1983. The statistical form of the algorithm is determined and has used to monitore the dynamic course of freezing/ thawing condition over whole Tibetan Plateau in 1983. The results show that the freezing / thawing condition is changed with several environmental factors such as elevation, direction of slop and latitude.
出处
《冰川冻土》
CSCD
北大核心
1996年第S1期329-335,共7页
Journal of Glaciology and Geocryology
关键词
地表土冻融
微波遥感
青藏高原
freezing / thawing condition of terrain soil, microwave remote sensing,Tibetan Plateau
