The challenge of global change: Responding through research, education, and data and information management

The Earth is a place of change. The geological record testifies that the Earth's environment has been subject to change over eons—much of it occurring slowly over many millennia, but some relatively rapidly over decades. The changes are in response to such phenomena as the migration of continents, the building and erosion of mountains, the reorganization of oceans, the orbital relationships of the planets to the Sun, variations in solar output, and even the catastrophic impacts of large meteorites. The underlying causes lead to changes on local, regional, and global scales: a succession of warm and cool epochs, the appearance and disappearance of large deserts and marshlands, new distributions of forests and grasslands, advances and retreats of great ice sheets, rising and falling sea and lake levels, and the extinction of vast numbers of species.