Less reliable water availability in the 21st century climate projections
Article first published online: 10 MAR 2014
© 2013 The Authors.
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.
Volume 2, Issue 3, pages 152–160, March 2014
How to Cite
Kumar, S., Lawrence, D. M., Dirmeyer, P. A. and Sheffield, J. (2014), Less reliable water availability in the 21st century climate projections. Earth's Future, 2: 152–160. doi: 10.1002/2013EF000159
- Issue published online: 15 APR 2014
- Article first published online: 10 MAR 2014
- Accepted manuscript online: 17 DEC 2013 09:15AM EST
- Manuscript Accepted: 10 DEC 2013
- Manuscript Revised: 5 DEC 2013
- Manuscript Received: 21 AUG 2013
- NSF. Grant Numbers: 0947837, 0830068
- NOAA. Grant Numbers: NA09OAR4310058, NA11OAR4310097
- NASA. Grant Number: NNX09AN50G
- U.S. Department of Energy. Grant Number: DE-FC02-97ER62402
- Water availability;
- climate projections;
The temporal variability of river and soil water affects society at time scales ranging from hourly to decadal. The available water (AW), i.e., precipitation minus evapotranspiration, represents the total water available for runoff, soil water storage change, and ground water recharge. The reliability of AW is defined as the annual range of AW between local wet and dry seasons. A smaller annual range represents greater reliability and a larger range denotes less reliability. Here we assess the reliability of AW in the 21st century climate projections by 20 climate models from phase 5 of the Coupled Model Intercomparison Project (CMIP5). The multimodel consensus suggests less reliable AW in the 21st century than in the 20th century with generally decreasing AW in local dry seasons and increasing AW in local wet seasons. In addition to the canonical perspective from climate models that wet regions will get wetter, this study suggests greater dryness during dry seasons even in regions where the mean climate becomes wetter. Lower emission scenarios show significant advantages in terms of minimizing impacts on AW but do not eliminate these impacts altogether.
Modeling of future water availability predicts that wet regions become wetter and dry regions become drier, leading to an increasing likelihood of seasonal droughts and floods in regions where such vulnerability is already high.