Impacts on Agricultural Productivity and Resource Availability
Climate change will affect crop and livestock production worldwide. These effects will stem from higher temperatures, longer growing seasons, greater carbon dioxide concentrations, changes in water availability, and increased variability in temperatures and water supplies, among other effects. These changes will also affect pest populations, which, in turn, affect crop and livestock production.
The U.S. Climate Change Science Program (CCSP) report "Synthesis and Assessment Product 4.3 (SAP 4.3): The Effects of Climate Change on Agriculture, Land Resources, Water Resources, and Biodiversity in the United States" integrates the Federal research efforts of 13 agencies on climate and global change. The report focuses on the next 25 to 50 years, and finds that climate change is already affecting U.S. water resources, agriculture, land resources, and biodiversity, and will continue to do so.
Adaptation and Market Effects
As a result of climate-induced changes in productivity and resources, agricultural yield potentials will change. Farmers will adapt to changing yield potentials by altering varietal selection, cropping patterns, grazing locations, and input use. These impacts will affect national and international markets; the prices of food, fiber, and energy; agricultural incomes; and the environment.
Adaptive responses to global climate change will likely include both the use of new crop varieties and replacement of one crop by another. Genetic combinations that are optimal for present growing environments may not be best as the growing environment changes. Plant breeding efforts can create varieties better suited to changed environments, and new genetic material could enhance efforts to breed new crop varieties. ERS research will examine farmers' responses to changing resource availability and productivity changes and will help in finding efficient alternatives. Farmer responses, possibly aided by policy changes, can help facilitate continued commodity production, conservation of natural resources, and food security in the face of climate change. The development of knowledge and tools to enable adaptation to climate change will improve the resilience of agricultural ecosystems.
Existing ERS research results, including studies not initially focused on climate change, can inform climate adaptation-related questions. For example, ERS research finds strong links between public and private investment in agricultural research and development and agricultural productivity growth in crops and livestock (see Economic Returns to Public Agricultural Research, September 2007). Productivity growth is uniformly stressed as a key component of meeting the challenges of climate and biofuel policy goals. Research on R&D trends, policies and benefits may provide valuable insights on options for improved targeting of scarce public and private resources to adapt to climate change effects and respond to climate change impacts.
In another example, ERS research on crop genetic resources (see Agricultural Resources and Environmental Indicators, 2006 Edition) indicates that these resources are essential to maintaining and improving agricultural productivity. But habitat loss, the dominance of scientifically bred over farmer-developed varieties, and genetic uniformity are all threats to continued diversity. The U.S. system for genetic resource conservation may lack sufficient diversity to reduce some crops' vulnerability to pests and diseases. Changing climatic regimes and associated increases in crop stressors (such as pests, drought, flood and early frost events) may increase demand for a wider range of genetic material.
Climate change is expected to make agricultural production more uncertain since producers must adapt to new and changing weather patterns and therefore also new and changing agricultural markets. Decision support refers to the provision of scientific information and tools to USDA agencies, stakeholders and producers to improve decision making. ERS research can provide the economic analysis on which decision support relies, as well as provide insights to help target scarce decision support dollars to improve net benefits.
Decision-support resources can be targeted at three broad categories: (1) monitoring, reporting, discussion and planning that uses state-of-the-science syntheses and assessments by decision makers, stakeholders, the media, and the general public (2) management decisions (i.e. climate adaptations) undertaken by agricultural producers, and managers of natural resources and climate services; and (3) climate change policy formulation, program development, and program implementation. Each of these categories has a unique set of stakeholders and requires different decision-support tools.
An example of ERS analysis on decision support tools can be found in The Value of Plant Disease Early Warning Systems: A Case Study of USDA's Soybean Rust Coordinated Framework (April 2006). Early-warning systems for plant diseases are valuable when the systems provide timely forecasts that farmers can use to inform their pest management decisions. This study evaluates the benefit of a website that provides real-time, county-level information to farmers on the spread of soybean rust. Results suggest that such information is valuable, and that its value depends most heavily on farmers' perceptions of the forecast's accuracy. The predicted increases in pest invasions associated with a changing climate suggest that the value of this type of decision support tool may increase.