On identifying relationships between the flood scaling exponent and basin attributes

Chaos. 2015 Jul;25(7):075405. doi: 10.1063/1.4916378.

Abstract

Floods are known to exhibit self-similarity and follow scaling laws that form the basis of regional flood frequency analysis. However, the relationship between basin attributes and the scaling behavior of floods is still not fully understood. Identifying these relationships is essential for drawing connections between hydrological processes in a basin and the flood response of the basin. The existing studies mostly rely on simulation models to draw these connections. This paper proposes a new methodology that draws connections between basin attributes and the flood scaling exponents by using observed data. In the proposed methodology, region-of-influence approach is used to delineate homogeneous regions for each gaging station. Ordinary least squares regression is then applied to estimate flood scaling exponents for each homogeneous region, and finally stepwise regression is used to identify basin attributes that affect flood scaling exponents. The effectiveness of the proposed methodology is tested by applying it to data from river basins in the United States. The results suggest that flood scaling exponent is small for regions having (i) large abstractions from precipitation in the form of large soil moisture storages and high evapotranspiration losses, and (ii) large fractions of overland flow compared to base flow, i.e., regions having fast-responding basins. Analysis of simple scaling and multiscaling of floods showed evidence of simple scaling for regions in which the snowfall dominates the total precipitation.

MeSH terms

  • Absorption, Physicochemical
  • Computer Simulation
  • Floods / statistics & numerical data*
  • Models, Chemical
  • Models, Statistical*
  • Rain*
  • Rivers / chemistry*
  • Soil / chemistry*
  • United States
  • Water / chemistry*

Substances

  • Soil
  • Water