Energy, water and land use: How do they affect each other in a changing climate?
Water supply, land use and energy production are all impacted by climate change. How these three sectors interact complicate climate change mitigation and adaptation decisions.
In May 2014, the U.S. Global Change Research Program released The Third National Climate Assessment. The report details current and predicted impacts in the United States resulting from a changing climate. Over 300 experts contributed to the three-year effort to develop the report. Impacts are described as they affect geographic regions, and sectors such as health, water, forests and agriculture.
An interesting chapter describes how water, energy and land use interact, and how climate change may affect those interconnected sectors. This way of looking at climate change paints a more complex picture than looking at each category separately.
Here is an example: During 2011 and 2012, much of the nation experienced drought and heat waves. High temperatures increased demand for electricity for air conditioning, and increased water withdrawals were needed by power thermo-electric plants to meet that need. At the same time, water demand increased to irrigate agricultural crops, reducing river flows in some areas needed by power plants. The poor harvest in 2012 intensified concerns about use of corn for food vs. use of corn for ethanol fuel.
As communities explore ways to mitigate and adapt to climate change, the dependence of energy supplies on land and water will come into focus. Every option to address these issues involves trade-offs. There are no simple solutions.
A lot of attention in recent years has focused on expanding production of biofuels from crops (especially corn), grasses and trees. Energy from biofuels can replace burning of fossil fuels and potentially reduce the amount of carbon dioxide and other greenhouse gasses entering the atmosphere. At the same time, these alternative sources of energy require increases in the amount of land dedicated to their production – for example, as much as 30 to 60 million acres may be needed to meet the U.S. Renewable Fuel Standard goal of 16 billion gallons of cellulosic biofuels (a type of fuel derived from many different plants other than corn or soybeans). Production also requires additional water supplies, which might be less available because of climate change-induced drought in many parts of the country.
Another example of tradeoffs associated with changing energy sources is the increased United States natural gas exploration and production, including Michigan. From a climate change perspective, natural gas has fewer impacts than energy produced from coal. Increased use of natural gas can reduce greenhouse gas emissions compared to use of other fossil fuels. On the other hand, additional land is needed in natural gas production areas to service the need for drilling sites, storage and transportation, with corresponding increases in environmental concerns. Also, most of the new supply results from use of hydraulic fracturing technology that injects a mixture of sand, water and chemicals into deep shale formations. Each well requires millions of gallons of water for this process - supplies that may be less available in some parts of country near drilling activity.
The report concludes by recommending a better understanding of the relationship between energy, water and land use. This increased knowledge can help improve evaluation of options for addressing climate change issues in Michigan and the rest of the nation.