Analyzing the relationship between land surface temperature and vegetation cover: a case of typical grassland in North China

摘要

Land surface temperature (LST) is widely thought to closely relate with vegetation cover (often expressed with VI, I.e. vegetation index), and negative LST/VI relationship is often used to estimate LST. However, this issue hasn't reached academic agreement yet as the LST/VI relation isn't linear, static and independent of other factors. This study examined the temporal variation of LST/VI relation and its link with soil moisture and with multi-phase MODIS products. The results indicate that in regions of high latitude where the condition of thermal energy is among ecologic limiting factors, the negative LST/VI relation doesn't hold true. The study also shows that the LST/VI association depends on soil moisture, which further complicates their relationship. This examination underlines that when the LST/VI slope is used to estimate LST, the uncertainty of LST/VI relation and the influence of soil moisture should both be carefully take into account.