Climate Change and Groundwater
|May 9, 2011||Posted by karmadsen under blog, Climate Change, Conservation, Desertification, Groundwater and Agriculture, Groundwater Pumping, Groundwater Regulation, water ecology, Water Rights|
This April, the U.S. Bureau of Reclamation published a report describing the squeeze climate change will put on the water budget of the Western United States. Groundwater is fairly sensitive to climate change.1 As temperatures increase, evapotranspiration will accelerate, impacting the entire hydrologic cycle and will lower the water level of aquifers and surface water bodies. With less snow and more rain falling, recharge patters will alter. The peak annual of recharge may shift towards the winter months and away from the spring. Recharge will also become more spread-out across seasons, as hydraulic storage in snow decreases.2
And all this could have an impact on our wallets. As change climate robs us of aquifer storage, the cost of water and food will climb. Modeling scenarios predict that warming temperatures will reduce the productivity of the Ogallala Aquifer, which accounts for 30% of all groundwater withdrawls in the US. 96% of water pumped from the Ogallala Aquifer goes to agriculture.1
The challenges is being taken seriously by the scientific departments of the federal government. In 2009, the Federal Climate Change and Water Working Group was formed to identify data gaps and support collaboration between government agencies and the scientific community. It includes NOAA, the USGS, the USACE, and the Bureau of Reclamations.
Simulated impact of climate change on long-term average annual diffuse groundwater recharge (under four different climate change models)3
1. U.S. Department of the Interior. (2011). SECURE Water Act Section 9503(c) – Reclamation Climate Change and Water 2011. Denver, Colorado: Bureau of Reclamation
2. Brekke, L.D., Kiang, J.E., Olsen, J.R., Pulwarty, R.S., Raff, D.A., Turnipseed, D.P., Webb, R.S., and White, K.D. (2009). Climate Change and Water Resources Management: A Federal Perspective. Circular 1331. Reston, Virginia: US Gelogical Survey. US Department of Interior.
2. M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden, and C.E. Hanson (eds). (2007). Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, 2007. Cambridge, United Kingdom and New York, NY, USA: Cambridge University Press. Section 3.4.2 Groundwater: Figure 3.5. Simulated impact of climate change on long-term average annual diffuse groundwater recharge. Availalbe at: http://www.ipcc.ch/publications_and_data/ar4/wg2/en/ch3s3-4-2.html.
*Image reproduced with permission given in the copyright of the Intergovenmental Panel on Climate Change