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.
Decision Support
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.