Spatial Grouping of Drought Using Standardized Precipitation Index in Isfahan Province

Document Type : Technical Note


1 Assoc. Prof., Dept. of Water Engineering, College of Agriculture, Isfahan University of Technology

2 Grad. Student of Desertification, Isfahan University of Technology

3 Assist. Prof., Dept. of Range and Watershed Management, Isfahan University of Technology


The determination of spatial distribution of drought attributes in Isfahan province is essential for the study and management of drought. In this study, using ten drought attributes based on severity, duration and frequency of standardized precipitation index in 45 stations in Isfahan province and cluster analysis of this attributes, 5 spatial groups were identified in Isfahan province. The spatial distribution of these groups shows that the change in severity and duration of drought is based on various longitudes and latitudes in Isfahan province.


1- Thompson, S. A. (1999). Hydrology for water management, 2nd Ed., A. A. Balkema, Rotterdam.
2- Smith, K. (2000). Environmental hazards, assessment risk and reduction disasters, 3rd Ed., Routledge, London.
3- Gottschalk, L. (1985). “Hydrological regionalization of Sweden.” J. Hydrological Sciences Journal, 30(3), 65-83.
4- Romero, R., Summer, G., Ramis, C., and Genoves, A. (1999). “A classification of the atmospheric circulation patterns producing significant daily rainfall in the Spanish Mediterranean area.”
International Journal of Climatology, 19(7), 765-785.
5- Singh, C. V. (1999). “Principal components of Monsoon rainfall in normal, flood and drought years over India.” International Journal of Climatology, 19(3), 639-652.
6- Stahl, K., and Demuth, S. (1999). Methods for regional classification of stream flow drought series: Cluster analysis, Technical report to the ARIDE project, No. 1, Freiburg University Publication.
7- Ramos, M. C. (2001). “Divisive and hierarchical clustering techniques to analyze variability of rainfall distribution patterns in a Mediterranean rgion.” Journal of Hydrology, 57(1), 123-138.
8- Moron, V. (1997). “Trend, decadal and interannual variability in annual rainfall of subequatorial and tropical North Africa (1990-1994).” International Journal of  Climatology, 17(5), 785-805.
9- Keyantash, J., and Dracup, J. A. (2002). “The quantification of drought: A evaluation of drought indices.” Bulletin of the American Meteorological Society, 38(8), 1167-1180.
10- Mckee, T. B., Doesken, N. J., and Kleist, J. (1993). “Drought monitoring with multiple timescales.” Preprints, 8th Conf. on Applied Climatology, Anaheim, CA, Amer. Meteor. Soc., 179-184.
11- Jobson, J. D. (1992). Applied multivariate data analysis, Vol. II: Categorical and multivariate methods, 2nd Ed., Springer-Verlag, New York.
12- SAS/STAT user’s guide; Version 8. (1999). SAS Institute  Inc., Cary, NC, USA.