White House Council on Environment Quality, Interagency Water Resources and Climate Change Adaptation Workshop Response Comments.

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1 White House Council on Environment Quality, Interagency Water Resources and Climate Change Adaptation Workshop Response Comments from American Society of Agronomy Crop Science Society of America Soil Science Society of America Contact: Dr. Karl Glasener, Director of Science Policy phone: November 12, 2009 General Comments (not focused on specific question 1-5). The big picture is that without climate change the demands on water for both agriculture and other uses (industry, residences, recreation, biodiversity, etc) will continue to intensify. Moreover, the rate at which this intensified competition will occur is far greater than the rate of impacts from climate change. So the big issue is how to produce enough food for 9+ billion people by 2040 and how to do so with much less water from irrigation than we presently use. Note that irrigated agriculture produces 40% of global food supply on 18% of the arable land area. It is critical to maintain increases in crop yields on irrigated land if we are to avoid expanding agriculture elsewhere at the expense of rain forests and wetlands. Conversion of these "Carbon-rich" ecosystems to crop land is the single greatest threat to accelerated greenhouse gas emissions and climate forcing. Agriculture must meet future food requirements on existing farmland, which means that average yields must increase by approximately 80% by Everything that needs to be done for water issues related to climate change should be done anyway to ensure adequate sustainable food production on existing farmland while using less irrigation water than we are currently using. Successfully addressing this issue is a prerequisite for addressing climate change, and it is much more immediate challenge than climate change. Responses to Workgroups 5 Questions 1. What do you see as the key impacts of a changing climate for water resources? Rain, Temperature, and Snowpack Melt Variation A key issue across much of the US will be changes in precipitation, temperatures, and rate of snow pack melt. Variation in any, especially in combination, will impact water resources greatly. Precipitation could decrease in important agricultural regions of the US. If temperatures increase, as is likely in the South West US, where population growth is continuing then both agricultural and urban sectors will have increased competition for increasingly scarce water resources going into the future. This impact will cause effects up through the headwaters of rivers and watersheds that supply much of the water to the Southwest. Climate models suggest selected areas that are currently very productive as rain fed agricultural areas, such as Central and Southern Europe extending into Asia, will see elevated temperatures and significantly lower precipitation during the growing season. Loss of productivity in these areas will increase production pressure on lands that are less likely to be impacted by climate change, such as those in the Midwestern U.S. Increased production pressures, likely to be

2 reflected in higher crop prices, will result in increased intensification of agricultural practices on existing farmed lands with favorable climate (such as those in the Midwestern U.S.). This will likely result in increased pressure to utilize environmentally sensitive land for crop production, and the elevated application of nutrients and pesticides to support elevated crop yields. This combination of pressure for elevated production, the practices that will likely be used, and increased frequency of extreme events in these areas will lead to increased challenges to maintain or improve water quality Water resources, like rainfall events, will likely undergo greater fluctuations. East of the Missouri River, this will be chronically problematic. West of the Missouri River (approximately) the fluctuations (depending on duration) could become very challenging for population centers. Climate models seem to indicate that total annual precipitation may not change much for the Great Plains. However, warmer temperatures will result in smaller and earlier snow melt, more erratic rainfall, higher intensity rainfall, and higher crop water requirements (evapotranspiration). These will result in less ability to store water and higher water requirements, and likely decreases in agricultural productivity in the Great Plains. Summer dew point temperatures are rising in Iowa (data unpublished and not sure about other locations, have not seen those data). Rising dew points result in extended diurnal periods of wet crop leaves and improved environment for disease infestation, especially fungal diseases. Fungicide applications will likely increase to combat fungal disease incidence with associated water quality impacts. In Western U.S. the ratio of precipitation to potential evaporation is falling and is projected to drop below 1 (PET greater than precipitation). This will increase demand for water, especially if crops are produced in these areas. Snowpack is a highly important natural mechanism for water storage. The impacts will cross the continental divide and will begin to influence those rivers and watersheds such as the N & S Platte River, and other Eastward flowing rivers that feed into the Missouri River. The Missouri river watershed incidentally is one of the largest watersheds in the United States and the largest watershed feeding the Mississippi River. The impact of global change is likely already being felt throughout the Rocky Mountains in the form of more rapid and earlier snowpack melt-off in the spring and pest damage (e.g. the Mountain Pine Beetle and possibly increased Spruce Beetle attacks). These extensive insect outbreaks have devastated enormous areas of forest and their outbreaks may be attributable to higher winter-time low-temperature minimums. The result is a synergistic effect wherein the loss of live trees results in an even more rapid and earlier snowpack melt-off and threatened water supply timing and amounts. Land Ownership vs. Renters The majority of harvested agricultural lands are rented. Research indicates renters have little incentive to implement conservation practices on land they do not own and more incentive to implement practices to insure short term profits - continuous row cropping monocultures with associated nutrient loading practices, for example. Frequency of intense storms is increasing in the Central U.S. (26% increase in frequency of extreme events between 1970 and 2002) and when coupled with practices associated with short term profit motivation on more than 50% of harvested lands, threats to water quality are amplified.

3 Cellulosic biofuel coupled with the changing climate could be devastating if the cellulosic material of choice comes from row crops. Row crop residues are the most important soil and water conservation tool in the upper Midwest. Excessive removal of row crop residues and application of higher levels of nutrients to replace those removed in the residue, coupled with the increased frequency of extreme events, amplifies water quality threats. Again, consider the incentives of a land renter vs. land owner/operator to forgo short term profits by leaving crop residue in the field. Forgoing the short term profit for the renter is a cost. For the owner it is an investment. The three way combination of potential residue removal, land renter profit motives, and elevated storm threats creates a serious water quality concern. Water Quantity Climate extremes, especially increased drought, will amplify the demands for irrigation water in drought affected areas. Ancient aquifers are currently being mined and many are no longer containing sufficient water to support irrigation. Additionally, aquifers such as the Ogallala or High Plains will likely experience increased water withdrawals in response to increased demands for crop production as areas within the world become less favorable for rain fed agriculture (see #3 under water quality). Floods, as have been recently experienced, in all likelihood will become more frequent and more extreme. Flood plains that are often highly productive will experience lower levels of production due to more frequent flooding damage to crops and increased soil and nutrient loss to surface waters 2. Are there key programs, policies, or other actions that Federal agencies should adopt to support or guide adaptation to climate change? It is essential to include and incorporate climate change into water management planning processes. The changes will be slow and the predictions of change are uncertain but they will occur. Adjustment of planning to include scenarios of climate change, not only sea level rise but also changes in the quantity and distribution of precipitation. These predictions will be incredibly challenging for south FL, but it is irrational to invest in hydrology-driven restoration without some idea of how the hydrology will change in the next 100 years. These changes could easily make restoration options which are attractive today become less attractive in the future and vice versa. Do not abandon current water planning strategies, but these plans should be adjusted to give consideration of changing temperature and precipitation and hydrology. Flood plain management will be increasingly critical. Land management practices that slow runoff and/or keep water where it falls will be increasingly important. Policies that diminish incentives for absentee land ownership of agricultural land will be increasingly important. Increasingly, renters basically require a government payment as their incentive for utilizing selected conservation practices, practices that would favorably affect water quality and, for many storm events, water quantity. This is very expensive for tax payers and it is not sustainable - when the payment stops, so do many of the conservation practice. Owner operators have internal incentives to preserve land they own and it is more often reflected favorably in practices used than when land is rented. Many of these practices will reduce runoff and favorably affect water

4 quality. If the land ownership profile does not change, increased expenditures for conservation practices will be required No single policy or policy change will fix this challenge or can be totally blamed for water challenges. However, a variety of policies are counterproductive relative to water quality and quantity. An example of such a policy that has negatively impacted water quality is the farm bill, especially the sections on farm subsidies that ultimately encourage a given crop to be produced at the exclusion of others in a given region Policies favoring dedicated perennials, especially in environmentally sensitive areas, for cellulosic biofuels create a win/win situation. Land ownership again is an issue as establishment of these crops is typically multi-year and not easily incorporated into short term lease arrangements. Increased water storage will be critical to maintaining current water resource supplies. Some breeding (crop adaptation) will help maintain productivity. Continuing research on irrigated crop production with deficit irrigation will also help maintain productivity. Agricultural and forestry disciplines are the key knowledge resources within the Federal and State workforces that have the ability to address the environmental issues associated with land management for adaptation to climate change. Rather than providing funding for research to be done by DOE and NASA to address long-term land-use and management issues, it should be apparent that USDA is the Department whose in-house research along with that of Land-Grant Universities best provides the adaptive long-term research to maintain and protect private and forest lands and keep them productive to help meet US needs for water resources as well as for food and fiber. 4. How can water resources and climate change adaptation planning be coordinated or integrated with other water resources planning efforts? Can you provide examples of such coordination already underway? Understanding the functionality of watersheds and how to manage their water is highly important. Presently some of the longest continuous research on watersheds is done by the USDA Agricultural Research Service at locations across the United States. Collectively the scientists operating these watersheds could likely provide information for a coordinated and integrated water resources planning effort. 5. Are there water resources and climate change studies or reports that the workgroup should consider in its work? Again, review the long-term watershed effort conducted by the USDA/ARS. Consultation with the active scientists and hydrologists who work on these watersheds can likely reveal relevant studies or study plans. Also please review the following:

5 Soil and Water Conservation Society Conservation implications of climate change: Soil erosion and runoff from cropland. Soil and Water Conservation Society, Ankeny, IA. Soil and Water Conservation Society Planning for Extremes: A report from a Soil and Water Quality workshop held in Milwaukee, WI November 1 3, Soil and Water Conservation Society, Ankeny, IA.