1. What is the Climate Change and Agriculture: Effects and Adaptation Technical Report?
The USDA peer-reviewed report offers a review of the expected consequences of climate change on U.S. agriculture, focusing on the next 25 to 100 years. Written by 56 expert authors from Federal service, universities, and non-government organizations, the report draws on more than 1,000 scientific citations, expanding and updating the information published in SAP 4.3: The Effects of Climate Change on Agriculture, Land Resources, Water Resources and Biodiversity in the United States.
Climate Change and Agriculture: Effects and Adaptation was developed in support of the National Climate Assessment, which is generated every four years through the U.S. Global Change Research Program. The report assesses our understanding of climate change’s influence on U.S. agriculture and potential adaptation strategies, but consistent with the requirements of such an assessment, makes no recommendations.
2. What are some of the report’s findings?
Projections for crops and livestock production systems reveal that climate change effects over the next 25 years will be mixed. Continued changes by mid-century and beyond, however, are expected to have generally detrimental effects on most crops and livestock.
Crop production is influenced by complex relationships with temperature, precipitation, carbon dioxide concentrations, weeds, pests, and disease. As temperatures increase, crop production areas may shift to regions where the temperature range for optimal growth and yield have moved, though production in any given location will be more influenced by available soil water during the growing season. Weed control costs total more than $11 billion a year in the U.S.; those costs are expected to rise with increasing temperatures and carbon dioxide concentrations.
3. Will livestock be affected, as well?
Yes, changing climate will also influence livestock production. Deviations from the narrow range of optimal core body temperatures for any specific type of livestock can damage performance, production, and fertility, limiting the production of meat, milk, or eggs. Changes in forage type and nutrient content will likely influence grazing management needs. Insect and disease prevalence are expected to increase under warmer and more humid conditions, diminishing animal health and productivity.
4. What other effects are anticipated for U.S. agriculture?
Changes in climate increasingly compromise the ability of ecosystems to provide necessary services to agriculture, including water quality and quantity. Climate change projections suggest increased variability in temperature and precipitation. Extreme events including dry spells, sustained droughts, and heat waves, can have large effects on crops and livestock. Although climate models are limited in their ability to predict the timing of individual extreme events, we can discern an increase in the incidence and intensity of such events. The timing of extreme events could affect sensitive stages of crop growth, and may place greater stresses on livestock, affecting the productivity of both crops and animals in the U.S. agricultural system.
5. Can U.S. agriculture adapt to changing climate?
U.S. agriculture has a long history of successful adaptation to climate variability. The accelerating pace and intensity of climate change, however, present new challenges for production.
Adaptation strategies used by U.S. producers include shifts in the timing of farming operations, selection of specialized crop and livestock varieties, pesticide use, technology, and other sustainable practices to increase resiliency. In the short term, these strategies will provide substantial adaptive capacity, protecting domestic producers and consumers from many of the effects of climate change - except the occurrence of protracted extreme events, such as drought. In the longer term, adaptation may be more difficult and costly as plant and animal species’ physiological limits are exceeded more frequently and crop and livestock system productivity become less predictable.
6. How will climate change influence the economics of agricultural production – will costs rise?
Research suggests that U.S. cropland agriculture will be fairly resilient to climate change in the short term, with expansion of irrigated acreage, regional shifts of crop acreage, and other adjustments partially compensating for yield effects caused by changing climate patterns. The degree of economic impact will vary regionally, with producers in some areas of the U.S. potentially benefitting and others suffering losses as a result of yield changes, adjustments to prices, and increased risk and economic variability. This short-term balance will likely give way to net losses in the longer term as temperatures continue to increase and other changes in climate become more pronounced. There remains a great deal of uncertainty about likely economic impacts due to uncertainty about climate projections and abiotic impacts as well as to limitations of research scope, including a common failure to address weather extremes, to incorporate potential pest impacts, and to consider climate impacts on livestock and non-commodity crops in a sophisticated way. Furthermore, considering climate effects on domestic yields alone is generally a poor predictor of U.S. welfare measures; domestic markets are highly interconnected with international markets and are therefore sensitive to yield and production changes worldwide.
7. What is USDA doing about climate change?
USDA is using the report’s findings to develop adaptation strategies and technical advice for producers that support decision-making under changing climate conditions. The Agricultural Research Service conducts research into the anticipated effects from climate change and evaluates adaptive strategies that increase the resilience of crops and livestock. The Foreign Agricultural Service sponsors scientific exchange programs to support climate change objectives. The Forest Service is involved on multiple fronts on maximizing carbon storage over the long-term. The Farm Service Agency manages programs which help to diminish atmospheric greenhouse gas concentrations while achieving other environmental benefits. The National Institute of Food and Agriculture supports climate objectives through research, education, and extension services. The Natural Resources Conservation Service provides financial and technical assistance to help agricultural producers become more resilient to climate change and reduce greenhouse gas emissions. And USDA’s Risk Management Agency has developed tools to assist with the management of limited irrigation water supplies during water shortages.
8. Where can I find more information?