Greenhouse Gases and Sulfate Aerosols

Climate models are often used to simulate future climates assuming specific changes in our environment. Predicted global temperature changes are shown by computing the effects of expected increased atmospheric levels of carbon-dioxide and sulfate aerosols. This simulation estimates potential global change using a coupled climate model that has interactive atmosphere, ocean, land, and sea ice components. A control climate was established by running the model for over 70 years with solar forcing and greenhouse gases held at present day levels. Two additional experiments were then performed, one of which has expected increases in greenhouse gases, such as carbon dioxide, and another, in which the additional effects of sulfate aerosols are included. The differences from the control for a running average of the Dec/Jan/Feb surface air temperature are shown in the next sequences which span over 70 years into the future. Note that some regions experience cooling relative to the control experiment, and other areas have less warming than with increasing greenhouse gases alone. Temperature and albedo differences are represented as shown below for a running average of the means of Dec/Jan/Feb.