Delineation of homogeneous hydrometeorological regions using wavelet-based global fuzzy cluster analysis

Bharath, R and Srinivas, VV (2015) Delineation of homogeneous hydrometeorological regions using wavelet-based global fuzzy cluster analysis. In: INTERNATIONAL JOURNAL OF CLIMATOLOGY, 35 (15). pp. 4707-4727.

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Abstract

Identification of homogeneous hydrometeorological regions (HMRs) is necessary for various applications. Such regions are delineated by various approaches considering rainfall and temperature as two key variables. In conventional approaches, formation of regions is based on principal components (PCs)/statistics/indices determined from time series of the key variables at monthly and seasonal scales. An issue with use of PCs for regionalization is that they have to be extracted from contemporaneous records of hydrometeorological variables. Therefore, delineated regions may not be effective when the available records are limited over contemporaneous time period. A drawback associated with the use of statistics/indices is that they do not provide effective representation of the key variables when the records exhibit non-stationarity. Consequently, the resulting regions may not be effective for the desired purpose. To address these issues, a new approach is proposed in this article. The approach considers information extracted from wavelet transformations of the observed multivariate hydrometeorological time series as the basis for regionalization by global fuzzy c-means clustering procedure. The approach can account for dynamic variability in the time series and its non-stationarity (if any). Effectiveness of the proposed approach in forming HMRs is demonstrated by application to India, as there are no prior attempts to form such regions over the country. Drought severity-area-frequency (SAF) curves are constructed corresponding to each of the newly formed regions for the use in regional drought analysis, by considering standardized precipitation evapotranspiration index (SPEI) as the drought indicator.

Item Type:	Journal Article
Publication:	INTERNATIONAL JOURNAL OF CLIMATOLOGY
Publisher:	WILEY-BLACKWELL
Additional Information:	Copy right for this article belongs to the WILEY-BLACKWELL, 111 RIVER ST, HOBOKEN 07030-5774, NJ USA
Keywords:	wavelets; hydrometeorological regions; cluster analysis; India; SPEI; regional drought analysis
Department/Centre:	Division of Mechanical Sciences > Civil Engineering
Date Deposited:	10 Feb 2016 05:58
Last Modified:	10 Feb 2016 05:58
URI:	http://eprints.iisc.ac.in/id/eprint/53209

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