Model Simulation of Past, Present and Future Climate Change

This animation shows the warming of the Earth's surface according to the results of the climate model (called the NCAR Community Climate System Model) from 1870-2100. This simulation is one of many using the CCSM for the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). It was a large effort sponsored by the National Science Foundation and the Department of Energy.

The model predicts that temperature increases over time and varies from place to place, which can be seen in the map. Red colors on the map indicate warmer temperature. And blue colors indicate cooler temperatures.

The graph shows how the model predicted average temperature change over time. To look into the possible future of climate change, the model was run with different scenarios about how humans will impact the amount of heat-trapping greenhouse gases in the atmosphere during the 21st Century.

• In the commitment scenario, there are no changes in greenhouse gases relative to the year 2000.
• In the B1 scenario, the amount of carbon dioxide greenhouse gas increases but only to 550 parts per million (ppm).
• In the A1B scenario the amount of carbon dioxide increases to 720 ppm.
• And in the A2 scenario it increases to 840 ppm.