The Mid-Atlantic Region and its climate: past, present, and future

The physical and human geographies and the historical climate of the Mid-At lantic Region of the United States are described to provide a baseline for an ongoing assessment of likely climate change impacts in the region. This region consists of 358 counties intersecting part or all of 8 states and 4 physiographic zones. This geographic diversity provides different sets of o ptions for societies to adapt to environmental changes. Since 1967, the reg ion's human population has grown in both number (19%) and income (116%), an d important local ecosystems are experiencing associated stresses. Since 18 95, the region's climate has become slightly warmer (+0.5 degrees C) and si gnificantly wetter (+10%), although the warming has abated recently. Projec tions indicate that these broad regional socio-economic, ecological and cli matic trends should persist through the 21st century. The significance of t hese changes in society, ecosystems and climate are evaluated in the more d etailed, sector-specific analyses in the subsequent articles of this Specia l.