Ts-NDVI space is a method used extensively to monitor drought, which combines spectral reflectivity and thermal infrared information. The temporary and spatial dependence and instability exist in Ts-NDVI space. Studying the features of Ts-NDVI space's structure and the relationship between the structure and climate feature is necessary to evaluate the Ts-NDVI space's temporary and spatial dependence and instability and to prove the drought monitoring and drought forecast. With the modis data and precipitation of Heilongjiang Province from 2000 to 2008, the study about interannual and seasonal variation of Ts-NDVI space and the relationship between the structural variation and climate characteristics are conducted. The single Ts-NDVI space based on primary satellite data and the composed general Ts-NDVI space based on multi-year satellite data are used in the study. The results show that: Some features are the variation of Ts-NDVI space's intercept and slope of dry and wet edge. The interannual variation ranges of the intercept and slope of dry and wet edge of Ts-NDVI space are all large, while the variation of slope is in the inverse way of the variation of intercept. The slope is to decrease if the intercept increases and vice versa, which is more obvious in wet. The seasonal variation of Ts-NDVI space is very evident and the variations of dry and wet edge are in the same way. The dry and wet edge's intercepts increase from spring to summer and decrease from summer to autumn. The max intercepts of both dry edge and wet edge are all in summer. The variation range of intercept is larger than that of slope. The wet edge is more sensitive to the environment, especially from spring to summer. The precipitation gives more impact on Ts-NDVI space, especially on wet edge. The composed general Ts-NDVI space by multi-year satellite data can reflect the climate feature within the same temporary and spatial scale. The intercept of dry edge can denote the min precipitation, and the intercept of wet edge can denote the max precipitation during the years. The correlation between the wet edge and the max precipitation is more evident.
