Supports the study of land use change in urban environments in three ways:

Temporal Urban Mapping

The USGS has been mapping past landscapes in order to predict metropolitan area's future urban form. Temporal urban mapping involves interpreting historical aerial photographs and historical USGS topographic map editions in order to map urbanized area extent, primary transportation routes, and land use data. NMD's temporal urban mapping also includes using contemporary data sources such as digital orthophotoquads and Landsat Thematic Mapper (TM) satellite imagery to map landscape change.

Urban Growth and Land Use Modeling

As part of NMD's urban growth research, the USGS is using the Deltatron Land Cover Model (LCM) developed by the University of California-Santa Barbara. The LCM version is capable either of predicting land use and land cover (LULC) or of modeling just the future urbanized area. The LCM predicts the probability of an area becoming urbanized on the basis of (or) by using the temporal urban mapping data themes, such as where urban lands presently occur, what lands have slopes that are likely to develop, and how the existing transportation infrastructure will influence future land use patterns. Generating an urban growth prediction (base scenario) using the LCM does not take into consideration factors such as socioeconomic projections for population, employment, or housing. Therefore, the model can only predict where urban growth is likely to occur on the basis of historical land use trends, current landscape characteristics, and the absence of constraints such as land use zoning.

Geographic Analysis

Temporal urban mapping databases and urban growth predictions are analyzed for patterns, rates, and trends in land use change. Population, socioeconomic, and environmental conditions are correlated with land use change to assess land transformation causes and impacts. For selected study areas, research:

• What are the rates of land use change?
• How do rates of change vary by geographic area?
• How do rates of change vary over time and space?
• What are the factors (e.g., driving, enabling, shaping, constraining, and sustaining) that influence land use patterns and how do they change temporally?
• What are the regional consequences of land use change?