Our aim is to help people understand global climate change — and how the factors that drive climate are changing. We start with climate diagnostics — people are usually most interested in climate change itself. But cause-and-effect analysis requires also data on climate forcings (which drive climate change) and feedbacks (which amplify or diminish climate change). Future climate depends on how climate forcings change — human-made greenhouse gases, especially carbon dioxide, and forcings that are not yet well measured, especially aerosols. The speed and degree of climate change also will depend upon how fast amplifying feedbacks such as cloud and sea ice changes, meltwater from Greenland and Antarctica, and permafrost melt come into play.
