Accessibility navigation


Uncertainty in the relationship between climate forcing and hydrological response in UK catchments

Downloads

Downloads per month over past year

Arnell, N. (2011) Uncertainty in the relationship between climate forcing and hydrological response in UK catchments. Hydrology and Earth System Sciences, 15 (3). pp. 897-912. ISSN 1027-5606

[img] Text - Published Version
· Please see our End User Agreement before downloading.

2170Kb

To link to this article DOI: 10.5194/hess-15-897-2011

Abstract/Summary

This paper assesses the relationship between amount of climate forcing – as indexed by global mean temperature change – and hydrological response in a sample of UK catchments. It constructs climate scenarios representing different changes in global mean temperature from an ensemble of 21 climate models assessed in the IPCC AR4. The results show a considerable range in impact between the 21 climate models, with – for example - change in summer runoff at a 2oC increase in global mean temperature varying between -40% and +20%. There is evidence of clustering in the results, particularly in projected changes in summer runoff and indicators of low flows, implying that the ensemble mean is not an appropriate generalised indicator of impact, and that the standard deviation of responses does not adequately characterise uncertainty. The uncertainty in hydrological impact is therefore best characterised by considering the shape of the distribution of responses across multiple climate scenarios. For some climate model patterns, and some catchments, there is also evidence that linear climate change forcings produce non-linear hydrological impacts. For most variables and catchments, the effects of climate change are apparent above the effects of natural multi-decadal variability with an increase in global mean temperature above 1oC, but there are differences between catchments. Based on the scenarios represented in the ensemble, the effect of climate change in northern upland catchments will be seen soonest in indicators of high flows, but in southern catchments effects will be apparent soonest in measures of summer and low flows. The uncertainty in response between different climate model patterns is considerably greater than the range due to uncertainty in hydrological model parameterisation.

Item Type:Article
Refereed:Yes
Divisions:Faculty of Science > School of Mathematical and Physical Sciences > Department of Meteorology
Interdisciplinary centres and themes > Walker Institute for Climate System Research
ID Code:19936
Publisher:Copernicus

Download Statistics for this item.

University Staff: Request a correction | Centaur Editors: Update this record

Page navigation