Welcome to Acta Prataculturae Sinica ! Today is Share:

Acta Prataculturae Sinica ›› 2014, Vol. 23 ›› Issue (2): 98-107.DOI: 10.11686/cyxb20140212

Previous Articles     Next Articles

Dynamic monitoring of drought based on Temperature Vegetation Dryness Index in Guangdong Province

WANG Ying1, WANG Jing-song1, YAO Yu-bi1,2, ZHAO Fu-nian1   

  1. 1.Key Laboratory of Arid Climatic Change and Reducing Disaster of Gansu Province, Key Open Laboratory of Arid Change and Disaster Reduction of China Meteorological Administration, Institute of Arid Meteorology, China Meteorological Administration, Lanzhou 730020, China;
    2.Meteorological Bureau of Dingxi City, Dingxi 743003, China
  • Received:2013-05-27 Online:2014-02-25 Published:2014-04-20

Abstract: Guangdong Province has been suffering from seasonal drought and the dynamic monitoring of drought by remote sensing data could be an important tool. The EVI-TS space was constructed by Moderate Resolution Imaging Spectro radiometer (MODIS) data, the dry and wet edges were extracted with a linear fitting method and then the Temperature Vegetation Dryness Index (TVDI) was calculated for Guangdong Province in 2011 and the Temporal-spatial distribution of drought was analyzed. 1) With an increase of the Enhanced Vegetation Index (EVI), the maximum land surface temperature decreased and the difference value between the maximum and minimum land surface temperature also decreased. The maximum and minimum land surface temperature both had an approximately linear relation to the EVI. The seasonal variation of EVI-TS space was obvious. When the temperature decreased, the EVI-TS space shrank and with a change of temperature, the intercept of the dry and wet edges changed correspondingly, i.e. the intercept was smaller in winter and bigger in summer. 2) Winter drought was very serious, while spring and autumn drought were also serious to some degree in Guangdong Province in 2011. The drought in winter and spring had similar distribution areas, and the grade weakened gradually from south to north. The drought in coastal areas was more serious than in inland areas. The geographical distribution of autumn drought approximately increased from south to north, which was the opposite to winter and spring droughts. According to the weather data in Guangdong Province, the results of the drought monitoring by remote sensing were in conformity with reality. 3) There was a significant negative correlation between TVDI and soil moisture and the results showed that the soil moisture can be successfully reflected by the TVDI data. The TVDI was negatively correlated with precipitation, temperature and mean relative humidity. TVDI had a high correlation coefficient with precipitation. TVDI was sensitive to precipitation on the station scale, which is a similar trend to the change of TVDI and precipitation in the time series. Continuous precipitation for a certain time was followed by a decline in the TVDI which indicated slight drought only and vice versa.

CLC Number: