Monitoring drought stress in north-eastern China by means of rainfall data and diachrone indices derived from Pathfinder AVHRR-imagery.

For climatic stress detection and monitoring in the Heilongjiang Province, north-eastem China, an indicator on the interannual vegetation state was extracted from the AVHRR Pathfinder image set (1981-2000) and compared to the rainfall variations over the growing season (June to August). The results show that the vegetation status does not closely depend on rainfall variations in this region. Temperatures, which showed a rapid augmentation in the northern high latitudes since the early 1980s, seem to be a more crucial limiting factor for vegetation growth. Rapid land cover change and large natural disasters are also likely to impact the relationship between rainfall and vegetation.