Investigation of Precipitation Droughts by Use of Kriging Method

By Tiao J. Chang,⁽¹⁾ Member, ASCE

Abstract:

Precipitation droughts were defined using monthly precipitation time series and different truncation levels-namely, 70%, 80%, 90%, and 95%-in which a 70% truncation level means that 70% of the recorded monthly precipitations are greater than or equal to the value. Conditional probabilities that droughts of certain truncation levels will advance to their next higher levels were estimated at each gage location. There are 21 precipitation stations selected in the Scioto River Basin, in Ohio, for the study of regional drought characteristics. The kriging method based on the minimum unbiased estimation was used to obtain a regional distribution of conditional drought probabilities for each truncation level. Contour lines of conditional probabilities for each truncation level were constructed to show possible drought-prone distributions for the ungaged region. This reflects the areal severity of water shortage in case of drought.

1. Prof., Civ. Engrg. Dept., Ohio Univ., Athens, OH 45701-2979 Note. This paper is part of the Journal of Irrigation and Drainage Engineering, Vol. 117, No. 6, November/December, 1991. ©ASCE, ISSN 0733-9437/91/0006-0935/ Paper No. 26493.





For more information on this or any other paper contact Terry Chang by email at tjchang@bobcat.ent.ohiou.edu

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