File(s) not publicly available

Reason: This item is currently closed access.

Bias correction of daily precipitation simulated by a regional climate model: a comparison of methods

journal contribution
posted on 27.07.2016 by Thomas Lafon, Simon J. Dadson, Gwen Buys, Christel Prudhomme
Quantifying the effects of future changes in the frequency of precipitation extremes is a key challenge in assessing the vulnerability of hydrological systems to climate change but is difficult as climate models do not always accurately simulate daily precipitation. This article compares the performance of four published techniques used to reduce the bias in a regional climate model precipitation output: (1) linear, (2) nonlinear, (3) γ-based quantile mapping and (4) empirical quantile mapping. Overall performance and sensitivity to the choice of calibration period were tested by calculating the errors in the first four statistical moments of generated daily precipitation time series and using a cross-validation technique. The study compared the 1961-2005 precipitation time series from the regional climate model HadRM3.0-PPE-UK (unperturbed version) with gridded daily precipitation time series derived from rain gauges for seven catchments spread throughout Great Britain. We found that while the first and second moments of the precipitation frequency distribution can be corrected robustly, correction of the third and fourth moments of the distribution is much more sensitive to the choice of bias correction procedure and to the selection of a particular calibration period. Overall, our results demonstrate that, if both precipitation data sets can be approximated by a γ-distribution, the γ-based quantile-mapping technique offers the best combination of accuracy and robustness. In circumstances where precipitation data sets cannot adequately be approximated using a γ-distribution, the nonlinear method is more effective at reducing the bias, but the linear method is least sensitive to the choice of calibration period. The empirical quantile mapping method can be highly accurate, but results were very sensitive to the choice of calibration time period. However, it should be borne in mind that bias correction introduces additional uncertainties, which are greater for higher order moments.

Funding

This work was funded by the UK Department for Food and Rural Affairs via the Environment Agency and by the UK Natural Environment Research Council (NE/011969/1).

History

School

  • Social Sciences

Department

  • Geography and Environment

Published in

International Journal of Climatology

Volume

33

Issue

6

Pages

1367 - 1381

Citation

LAFON, T. ... et al., 2013. Bias correction of daily precipitation simulated by a regional climate model: a comparison of methods. International Journal of Climatology, DOI: 10.1002/joc.3518.

Publisher

John Wiley & Sons (© Royal Meteorological Society)

Version

VoR (Version of Record)

Publisher statement

This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/

Publication date

2013

Notes

Closed access.

ISSN

0899-8418

eISSN

1097-0088

Language

en

Exports