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Global Climate Models:

What They Do And Do Not Show By Brad Udall Director CU-NOAA Western Water Assessment

Computer-based climate models allow scientists to investigate how changes in sunlight, concentrations of greenhouse gases, tiny atmospheric particles called aerosols, and even volcanoes, might affect the Earth’s climate. The models are critical because scientists have no way to otherwise experiment on the Earth. Today’s sophisticated global climate models, or GCMs, are derived from the first ones created in the 1960s and from weather prediction models dating to the 1950s. Projecting climate is easier than predicting weather because scientists are not interested in the forecasts for a given day in the future. Instead, they are concerned about long-term averages, extremes and patterns that determine climate. At their heart, GCMs are mathematical representations of the Earth’s natural systems including the atmosphere, oceans, icecovered areas, land and vegetation. The models are some of the most complex computer codes written by humans and run on the largest supercomputers in the world. Approximately 25 climate models have been developed in about 12 modeling centers around the world. The U.S. has three major modeling centers: NOAA’s Geophysical Fluid Dynamics Laboratory in Princeton, N.J.; NASA’s Goddard Institute for Space Studies in New York City; and Boulder’s National Center for Atmospheric Research.

Citizen’s Guide to Colorado Climate Change

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Citizen's Guide to Colorado Climate Change  
Citizen's Guide to Colorado Climate Change  

This guide presents a range of contemporary climate change information presented by Colorado experts.