FREQUENCY ANALYSIS OF MEAN MONTHLY STREAM FLOW IN CORUH BASIN TURKEY

YERDELEN C., KAHYA E.

Fresenius Environmental Bulletin, vol.19, no.7, pp.1300-1311, 2010 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 19 Issue: 7
  • Publication Date: 2010
  • Journal Name: Fresenius Environmental Bulletin
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED)
  • Page Numbers: pp.1300-1311
  • Istanbul Technical University Affiliated: No

Abstract

This paper analyzes mean monthly stream-flow data recorded from 29 stream-flow gauging sites in Coruh basin, Turkey. In regional mean monthly stream-flow analysis based on L-moments, at first, discordancy measures have been used to screen data on each of the 29 gauging sites. Homogeneity of the basin has been tested using L-moment-based heterogeneity measure. We divided Coruh basin into 5 subregions and single sites. A number of L-moments-based frequency distributions (i.e., generalized logistic (GLO), generalized extreme value (GEV), generalized Pareto (GPA), generalized normal (GNO), Pearson type III (PE3), and 5-parameter Wakeby (WAK) distribution) have been used in order to find a suitable distribution for quantile estimates. We determined that the GNO, GPA, and WAK distributions appeared to be a robust distribution in Coruh basin. Finally, we carried out the Monte Carlo simulations for the quantile estimation accuracy. As a result, the GPA, GNO and WAK distributions generated similar quantiles.