Global Climate Change

Many lines of scientific evidence show the Earth's climate is changing. This page presents the latest information from several independent measures of observed climate change that illustrate an overwhelmingly compelling story of a planet that is undergoing global warming. It is worth noting that increasing global temperature is only one element of observed global climate change. Precipitation patterns are also changing; storms and other extremes are changing as well.

Climate is the average pattern of weather over the long term. The earth’s climate has warmed and cooled for millions of years, since long before we appeared on the scene. There’s no doubt that the climate is growing warmer currently; indications of that change are all around us.

Though climate change isn’t new, the study of how human activity affects the earth’s climate is. The exploration of climate change encompasses many fields, including physics, chemistry, biology, geology, meteorology, oceanography, and even sociology.

At this Web site, you can explore scientific data relating to the atmosphere, the oceans, the areas covered by ice and snow, and the living organisms in all these domains. You’ll also get a sense of how scientists study natural phenomena—how researchers gather evidence, test theories, and come to conclusions.