Land, Energy and Water Systems: Intersects and Climate [INVITED]

Climate change affects water, and land resources, and with growing human activity, each of these sectors relies increasingly on the others for critical resources. Events such as drought across the South Central U.S. during 2011 demonstrate that climatic impacts within each of these sectors can cascade through interactions between sectors. Energy, water, and land resources are each vulnerable to impacts on either of the other two sectors. For example, energy systems inherently require land and water. Increased electricity demands to contend with climate change can impose additional burdens on overly subscribed water resources. Within this environment, energy systems compete for water with agriculture, human consumption, and other needs. In turn, climate driven changes in landscape attributes and land use affect water quality and availability as well as energy demands. Diminishing water quality and availability impose additional demands for energy to access and purify water, and for land to store and distribute water.

In some situations, interactions between water, energy, and land resources make options for reducing greenhouse gas emissions vulnerable to climate change. Energy options such as solar power or biofuel use can reduce net greenhouse gas emissions as well as U.S. dependence on foreign resources. As a result, the U.S. is expanding renewable energy systems. Advanced technology such as carbon dioxide capture with biofuels may offer a means of removing CO2 from the atmosphere.

But as with fossil fuels, renewable energy sources can impose significant demands for water and land. For example, solar power mayrequire significant land to site facilities and water for cooling or to produce steam. Raising crops to produce biofuels uses arable land and water that might otherwise be available for food production. Thus, warmer and drier climate can compromise these renewable energy resources, and drought can stress water supplies creating competition between energy production and agriculture. These kinds of stresses often initiate innovated technological developments, such as dry cooling to reduce water demands in the U.S. Southwest for utility-scalesolar development, however, the need for large areas of land remain, and often, large land tracts in this region are under Federal ownership and used as conservation or wildlife refuges.

Conflicting stakeholder views, institutional commitments, and international concerns can constrain options for reducing vulnerability to climate change, and interactions among water, energy, and land resource sectors can intensify such constraints. While management decisions may focus primarily on one of these resource sectors, where the three sectors are tightly coupled, options for mitigating or adapting to climate change may be limited more than expected. For example, the Columbia River Treaty between Canada and the U.S. emphasizes hydroelectric power and flood control, but with warmer temperatures and drier summers projected for the Northwest, diminishing water supplies will result in increased pumping for resource production (i.e., deeper groundwater) and transmission. Finally, coordinated water management for agriculture, ecosystem services, and hydropower will be an important aspect of adaptation not necessarily accommodated by the Treaty.