Published in

American Geophysical Union, Journal of Geophysical Research: Atmospheres, 2(119), p. 594-613, 2014

DOI: 10.1002/2013jd020505

Links

Tools

Export citation

Search in Google Scholar

Robust Ensemble Selection by Multivariate Evaluation of Extreme Precipitation and Temperature Characteristics

Journal article published in 2014 by Stephan Thober, Luis Samaniego ORCID
This paper is made freely available by the publisher.
This paper is made freely available by the publisher.

Full text: Download

Green circle
Preprint: archiving allowed
Green circle
Postprint: archiving allowed
Orange circle
Published version: archiving restricted
Data provided by SHERPA/RoMEO

Abstract

[1] Extreme hydro-meteorological events often cause severe socio-economic damage. For water resources assessments and policy recommendations, future extreme hydro-meteorological events must be correctly estimated. For this purpose, projections from Regional Climate Models (RCMs) are increasingly used to provide estimates of meteorological variables such as temperature and precipitation. The main objective of this study is to investigate whether a full ensemble or a subset of RCMs reproduces the spatio-temporal variability of observed extremes better than single models. The implications for policy recommendations and impact assessments are then discussed. In particular, the key conditions under which a subset of RCMs could be used for impact assessments are examined. Temperature and precipitation fields of 13 ENSEMBLES RCMs are compared against observations from Germany between 1961 and 2000. Eleven indices characterizing extreme meteorological events were selected for this comparison. The ability of the individual RCMs is estimated based on an overall score and a rejection rate. The former quantifies the biases of these indices. The latter estimates the mean statistical significance quantified by the Wilcoxon rank-sum test. The performance of all possible combinations of RCMs is investigated. Computationally feasible algorithms for finding the best-performing subensemble are also presented and evaluated. One of the proposed algorithms is able to find subensembles with the lowest rejection rate, which are useful for either policy recommendations or impact assessments. These subsets of RCMs showed smaller and less significant bias than single RCMs or the full ensemble over several regions.