Climate change impacts on Northeast agriculture
CALS Impact Statement
Prior climate change studies have focused on major world food crops such as wheat and maize, but this is not relevant to the Northeastern U.S. (NE) agriculture economy, which is dominated by dairy and high-value horticultural crops. We used new, high resolution climate projections to evaluate factors relevant to major NE commodities. A longer growing season could create new opportunities for farmers with enough capital to take risks on new crops (assuming a market for new crops can be developed). However, farmers will face new challenges from marginally over-wintering insects, and increased threat of invasive weeds and insects shifting their range northward. Water management will be more challenging due to increased frequency of flooding from high rainfall events, and yet also increased risk of short-term droughts during late summer. By mid-century warmer winters will negatively affect yields of our apple and native grape varieties that require more than 1000 hours of “winter chill” to bloom properly in spring. Of more immediate concern are erratic winters leading to more freeze damage from premature mid-winter leaf-out, or delayed hardening in fall. Increased summer heat stress will have a substantial negative impact on dairy milk production by mid century. Farmer adaptations to climate change will not be cost- or risk-free, and the impact on individual farm families and rural communities will depend on commodity produced, available capital, and timely, accurate climate projections.
Most analyses of climate change impact on U.S. agriculture are based on crop model simulations for one or more of the major world food crops such as wheat, maize (field corn), rice, and soybean. The problem with this approach for the Northeastern U.S. (NE) is that, with the exception of corn, these crops are relatively unimportant economically to the region compared to high value horticultural crops such as apples, grapes, cabbage, and sweet corn. The dairy industry, which dominates the NE agriculture economy (more than $1.5 billion per year for New York state alone), has not been well-addressed in prior analyses. Another shortcoming of many prior analyses is that potential effects of climate change on weeds, insects, and disease pests are not considered, as it is assumed that farmers will adapt with appropriate changes in control strategies as needed. Little thought has been given to farmer risks and costs involved in adapting to a changing and very uncertain climate.
We conducted an analysis based on output from new high resolution climate projections for the region, run with the “business as usual” (A1fi) and “lower” (B1) future greenhouse gas emissions scenarios developed by the Intergovernmental Panel on Climate Change. We evaluated future impacts on: the frost-free period; the frequency of high temperature stress thresholds affecting crops and dairy milk production; winter temperature effects on winter chill requirement for maximum yield of fruit and other crops; minimum winter temperature effects on potential northward migration of invasive weeds and insect pests, and frequency of summer droughts. We also considered farmer adaptation options in relation to potential costs, risks, and vulnerabilities. The results were published as part of a comprehensive document, “Confronting Climate Change in the U.S. Northeast, released in July 2007, and available on-line at www.northeastclimateimpacts. Several press events were held in July for the public release, with coverage in the New York Times, Boston Globe, Washington Post, and dozens of other newspapers, as well as television and radio broadcasts across the region. Since the release, Wolfe as lead author of the agriculture section has held briefings with NYS Department of Environmental Conservation (DEC), Senator Clinton’s staff, and also given dozens of presentations to farmer, gardener, and general public audiences. Results are also “in press” in a peer reviewed journal.
Leadership at the NYSDEC has adopted the report as the foundation of a new major emphasis on climate change preparedness at the agency. Plans for briefings with the New York Department of Agriculture and Markets, and a similar agency in Pennsylvania, are underway. Many Cornell Cooperative Extension staff have been made aware of the findings, either through presentations to farmer or Extension audiences, or through the website, and are integrating the information into their education programs. The New York State Water Resources Institute, has adopted climate change as a major new theme of its activities. Many hundreds of farmers have now heard directly from Wolfe or others involved in the project, and/or have read about the results at the website or through publications in grower outlets, such as a comprehensive article in the September 2007 issue of The Farmer (Northeast Organic Farming Association, NOFA, periodical). Integrated Pest Management (IPM) specialists throughout the region now routinely consider the reality of climate change in planning the timing of scouting programs and in developing plans for monitoring potentially invasive insect and weed pests.