Abstract
This study proposes a modified vegetation-dependent temperature-vegetation dryness index (TVDI) model for analyzing regional drought disasters in the Beijing-Tianjin-Hebei Metropolitan Region (BTHMR) of China. First, MODIS monthly normalized difference vegetation index (NDVI), land surface temperature (LST) data and land use/cover data (Land cover type2) were pre-processed as a consistent big dataset. The land use/cover data were modified and integrated into six primary types. Then, these land types were used as the base data layer to calculate the TVDI by parameterizing the relationship between the MODIS NDVI and LST data. By emphasizing different types of land uses, this study was able to compare and analyze the differences of the TVDI indices between the entire study area (no consideration of the land types) and the six classified land uses. The soil moisture data were used to validate the modified TVDI values based on different land uses, which confirmed that the modified model more effectively reflected drought conditions. Finally, the aforementioned model was used to analyze the temporal and spatial variation of drought experienced by vegetation cover from 2000 to 2014. The results of the modified model were validated with the synchronized soil moisture and precipitation data. The case study clearly demonstrated that the modified TVDI model, which is based on different vegetation indexes, could better reflect the drought conditions of the study area.
Highlights
IntroductionPeriodically occurring and complex natural disaster. Prolonged drought causes reductions in crop production on one hand and directly affects the sustainable development of agriculture and societal stability on the other hand [1,2]
Drought is a common, periodically occurring and complex natural disaster
As a consequence of global warming, climate change directly influences the distribution of precipitation and spatial patterns [5,6], which, again, results in prolonged droughts in certain areas
Summary
Periodically occurring and complex natural disaster. Prolonged drought causes reductions in crop production on one hand and directly affects the sustainable development of agriculture and societal stability on the other hand [1,2]. As a consequence of global warming, climate change directly influences the distribution of precipitation and spatial patterns [5,6], which, again, results in prolonged droughts in certain areas. Since the 1980s, the temperature in the BTHMR has markedly increased; reduced precipitation, a shortage of water resources, and the drying of the climate have become evident, causing frequent meteorological disasters. These meteorological disasters have caused enormous economic lost in this area; an annual average of tens of billions of Yuan has been lost since the 1990s, and the loss has increased every year [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
