Evaluation of changing surface water abstraction reliability for supplemental irrigation under climate change

Rio, M.; Rey, D.; Prudhomme, C.; Holman, I.P.. 2018 Evaluation of changing surface water abstraction reliability for supplemental irrigation under climate change. Agricultural Water Management, 206. 200-208. https://doi.org/10.1016/j.agwat.2018.05.005

Before downloading, please read NORA policies.

Preview

Text
N520194PP.pdf - Accepted Version
Download (2MB) | Preview

Official URL: http://dx.doi.org/10.1016/j.agwat.2018.05.005

Abstract/Summary

In many temperate parts of the world, supplemental irrigation is crucial to assure both crop yield and quality. Climate change could increase the risks of irrigation being restricted by increasing crop water requirements and/or decreasing water availability. In England, water abstraction for irrigation is limited by maximum annual volumetric limits, as specified in the abstraction licences, and surface water abstraction restrictions imposed by the regulator during drought. This paper assesses how climate change might impact future irrigation abstraction reliability from surface water in England. Firstly, the probability of annual abstraction being close to the maximum licence limit was estimated for the baseline (1961–1990) and future (2071–2098) periods in each catchment based on observed relationships between annual weather and irrigation abstraction in three licence usage groups. Secondly, the current river discharge triggers for mandatory drought restrictions were used to assess the annual probability of surface water abstraction restrictions being imposed by the regulator in each period. Results indicate significant future increases in irrigated abstraction licence use due to an increase in aridity, particularly in the most productive agricultural areas located in eastern and southern England, assuming no adaptation. The annual probability of having less than 20% licence headroom in the highest usage group is projected to exceed 0.7 in 45% of the management units, mostly in the south and east. In contrast, irrigators in central and western England face an increased risk of drought restrictions due to the lower buffering capacity of groundwater on river flows, with the annual probability of mandatory drought restrictions reaching up to 0.3 in the future. Our results highlight the increasing abstraction reliability risks for irrigators due to climate change, and the need for the farming community and the regulator to adapt and collaborate to mitigate the associated impacts.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.1016/j.agwat.2018.05.005
UKCEH and CEH Sections/Science Areas:	UKCEH Fellows
ISSN:	0378-3774
Additional Keywords:	drought, England, resilience, irrigated agriculture, risk, adaptation
NORA Subject Terms:	Hydrology
Date made live:	31 May 2018 14:33 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/520194

Item Type:

Publication - Article

Digital Object Identifier (DOI):

https://doi.org/10.1016/j.agwat.2018.05.005

UKCEH and CEH Sections/Science Areas:

UKCEH Fellows

ISSN:

0378-3774

Additional Keywords:

drought, England, resilience, irrigated agriculture, risk, adaptation

NORA Subject Terms:

Hydrology