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Climate influences the environment, natural resources, the economy, and other aspects of life in all parts of the world. Natural and human contributions to changes in climate may have substantial environmental, economic, and societal consequences. Decision-makers, resource managers, and other interested individuals need reliable science-based information to make informed decisions regarding policy and actions. In order to understand climate change and its impacts, we need to understand some of the range and complexity of the climate system itself.
What is the Difference between Weather and Climate?
Weather consists of the hourly and day-to-day variations in the meteorological conditions, such as precipitation or temperature. Climate is the average weather conditions in given locations over longer periods of time.
What is Climate Change?
Climate change is any long-term, significant shift in the “average climate” that a given region experiences. Average climate may include average temperature, precipitation and wind patterns, as well as natural variability and extremes.
What is the Difference between Climate Change and Climate Variability?
Climate change involves significant changes in the climate system over time periods ranging from decades to millions of years.
Climate variability refers to inherent fluctuations within the climate system. These fluctuations can occur on a variety of timescales, from seasonal and annual,to longer term fluctuations, like the “little ice age” of the 15th through the 18th centuries. Examples of seasonal fluctuations are the El Niño and La Niña phenomena. The El Niño phenomenon is “characterized by unusually warm oceanic temperatures while La Niña brings unusually cool oceanic temperatures in the central and eastern equatorial Pacific" (NOAA, 2010).
The Greenhouse Effect and Climate Change
Greenhouse gases (GHGs), such as carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and water vapor (H2O) are a critical part of our climate system. These gases are effective in trapping heat at the earth’s surface. Without GHGs, most of the currently cultivated regions of the earth would be too cold for agricultural production. However, human activity is contributing to increases in GHG concentrations in the atmosphere and the increases are causing potentially detrimental changes in temperature and other aspects of climate. Although agricultural sources account for only 6 percent of the total GHG emissions in the USA, many sources can be reduced with minimal economic impact. Producers have opportunities to employ practices that save money and time, and take advantage of market forces that may lead to new commodities such as, carbon, bioenergy crops, and GHG emissions reductions.
Climate Change Impacts on Agricultural Production
Climate change and climate variability present a challenge to ecologically, economically, and socially sustainable land management. Drought, floods, and temperature fluctuations due to climate change can directly affect agricultural operations through damage to crops and livestock. Indirect effects of climate change include higher soil erosion rates, more invasive species, and changes in soil and vegetative relationships. Climate change, much like climate variability, will likely have significant regional differences, and the consequences of these changes will not be spread evenly, or even in the same manner, across the planet. Therefore, regionally and locally unique solutions for adapting to these changes will need to be developed.
The Natural Resources Conservation Service (NRCS) is focusing global climate change efforts in several areas: 1) quantifying the effects of conservation practices on greenhouse gas emissions and carbon sequestration; 2) refining incentives in conservation programs to address the effects of climate change on agriculture; 3) developing and encouraging the use of conservation practices and systems that reduce GHG emissions; and 4) enhance opportunities to increase farm profitability on the emerging voluntary markets.
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