Preprints
https://doi.org/10.5194/hess-2021-123
https://doi.org/10.5194/hess-2021-123

  17 Mar 2021

17 Mar 2021

Review status: a revised version of this preprint is currently under review for the journal HESS.

Storylines of UK drought based on the 2010–2012 event

Wilson C. H. Chan1, Theodore G. Shepherd1, Katie A. Smith2, Geoff Darch3, and Nigel W. Arnell1 Wilson C. H. Chan et al.
  • 1Department of Meteorology, University of Reading, Reading, UK
  • 2UK Centre for Ecology and Hydrology, Wallingford, UK
  • 3Anglian Water, Peterborough, UK

Abstract. Spatially extensive multi-year hydrological droughts cause significant environmental stress. Given the impacts of climate change, the UK is expected to remain vulnerable to future multi-year droughts. Existing approaches to quantify hydrological impacts of climate change are often scenario-driven and may miss out plausible outcomes with significant impacts. Event-based storyline approaches aim to quantify storylines of how observed events could hypothetically have unfolded in alternative ways. This study uses the 2010–2012 drought, the most recent period of severe hydrological drought in the UK, as a basis, and analyses counterfactual storylines based on changes to 1) precondition severity, 2) temporal drought sequence, and 3) climate change. Evidence from multiple storylines shows that maximum intensity, mean deficit and duration of the 2010–2012 drought were highly conditioned by its meteorological preconditions, particularly for northern catchments at shorter time scales. Recovery time from progressively drier preconditions reflect both spatial variation in drought conditions and the role of physical catchment characteristics, particularly hydrogeology in the propagation of multi-year droughts. Two plausible storylines of an additional dry year with dry winter conditions repeated either before the observed drought or replacing the observed dramatic drought termination confirm the vulnerability of UK catchments to a three dry winter scenario. Applying the UKCP18 climate projections, we find that drought conditions worsen with global warming with a mitigation of drought conditions by wetter winters in northern catchments at high warming levels. Comparison of the storylines with a benchmark drought (1975–76) and a protracted multi-year drought (1989–93) shows that for each storyline, drought conditions could have matched and exceeded those experienced during the past droughts at catchments across the UK, particularly for southern catchments. The construction of storylines based on observed events can complement existing methods to stress test UK catchments against plausible unrealized droughts.

Wilson C. H. Chan et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on hess-2021-123', Anonymous Referee #1, 28 Apr 2021
    • AC1: 'Reply on RC1', Wilson Chan, 24 May 2021
  • RC2: 'Comment on hess-2021-123', Gemma Coxon, 14 Jun 2021
    • AC2: 'Reply on RC2', Wilson Chan, 29 Jun 2021

Wilson C. H. Chan et al.

Wilson C. H. Chan et al.

Viewed

Total article views: 678 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
487 178 13 678 28 3 5
  • HTML: 487
  • PDF: 178
  • XML: 13
  • Total: 678
  • Supplement: 28
  • BibTeX: 3
  • EndNote: 5
Views and downloads (calculated since 17 Mar 2021)
Cumulative views and downloads (calculated since 17 Mar 2021)

Viewed (geographical distribution)

Total article views: 445 (including HTML, PDF, and XML) Thereof 445 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 24 Jul 2021
Download
Short summary
This study selects the 2010–12 UK drought and investigates alternative unfolding of the drought from changes to its attributes. We created storylines of drier preconditions, alternative seasonal contributions, third dry winter and climate change. Storylines of the 2010–12 drought show alternative situations that could have resulted in even worse conditions than observed. Event-based storylines explore plausible situations that may lead to high-impacts and help stress test existing systems.