Many lines of evidence, from ice cores to marine deposits, indicate that Earth’s temperature, sea level, and distribution of plant and animal species have varied substantially throughout history. Ice cores from Antarctica suggest that over the past 400,000 years global temperature has varied as much as 10 degrees Celsius through ice ages and periods warmer than today. Before human influence, natural factors (such as the pattern of earth’s orbit and changes in ocean currents) are believed to be responsible for climate changes.
The Climate System.
Past Climate and Trends
Since the Industrial Revolution, human influences including fossil fuel emissions, urbanization, large-scale agriculture, deforestation and other activities have disturbed the natural system. Many scientists suspect that these activities have contributed a portion of the 1 degree Celsius increase in global average temperature over the past century and are in some part responsible for ocean warming, rising sea levels, melting glaciers and retreating sea ice.
The following resources are intended to provide a basic understanding of earth’s climate system, natural and human-related factors that influence climate change, climate variability, and weather, and an overview of regional and global trends in temperature and precipitation that influence management decisions made by animal producers. Related: How Does Climate Change Impact Animal Agriculture?
Fact sheet: Why Does Climate Change? (look below the preview box and title for a download link)
If you would like to use the video, slides, or factsheet for educational programs, please visit the curriculum page for download links for this and other climate change topics.
- IPCC Fifth Assessment Report (AR5) on Climate Change – Intergovernmental Panel on Climate Change (2014)
- National Climate Assessment (2014, multiple federal agencies)
- Carbon, Climate Change and Controversy (Shepherd, J. M., 2011)
- Global Climate Change Causes– web site (NASA, 2012)
- Climate Change Indicators for the US (EPA,2013)
- Climate Monitoring (NOAA)
- NOAA Climate Measurement Definitions
About the Author
Pam Knox is a climatologist at the University of Georgia Athens. She has extensive experience in climate and agriculture topics. More about Pam….
This page was developed as part of a project “Animal Agriculture and Climate Change” an extension facilitation project to increase capacity for ag professionals. It was funded by USDA-NIFA under award # 2011-67003-30206.