A scheme for meteorological drought analysis at various temporal and spatial scales based on a spatial Bayesian interpolation of drought severity derived from Standardized Precipitation Index (SPI) values at observed stations is presented and applied to the Huai River basin of China in this paper, using monthly precipitation record from 1961 to 2006 in 30 meteorological stations across the basin. After dividing the study area into regular grids, drought condition in gauged sites are classified into extreme, severe, moderate and non drought according to SPIs at month, seasonal and annual time scales respectively while that in ungauged grids are explained as risks of various drought severities instead of single state by a Bayesian interpolation. Subsequently, temporal and spatial patterns of drought risks are investigated statistically. Main conclusions of the research are as follows: (1) drought at seasonal scale was more threatening than the other two time scales with a larger number of observed drought events and more notable variation; (2) results of the Mann–Kendall test revealed an upward trend of drought risk in April and September; (3) there were larger risks of extreme and severe drought in southern and northwestern parts of the basin while the northeastern areas tended to face larger risks of moderate drought. The case study in Huai River basin suggests that the proposed approach is a viable and flexible tool for monitoring meteorological drought at multiple scales with a more specific insight into drought characteristics at each severity level.
|Number of pages
|Stochastic Environmental Research and Risk Assessment
|Published - Oct 31 2014
Bibliographical noteFunding Information:
This work was jointly supported by the Major Program of National Natural Science Foundation of China (51239004), the National Basic Research Program of China (2010CB951102) and the National Natural Science Foundation of China (51009150). The authors are grateful to Doctor David Emanuel from University of California Davis and three anonymous reviewers for their helpful comments that substantially improved the manuscript.
© 2014, Springer-Verlag Berlin Heidelberg.
- Bayesian interpolation
- Drought assessment
- Huai River basin
- Standardized Precipitation Index
- Temporal and spatial patterns