urban areas agricultural forested water

These are land use maps for the White Clay Creek watershed in southeastern Pennsylvania and northeastern Delaware. The left image was derived from a 1996 Landsat TM satellite image, while the right image is the SLEUTH predicted land use for the year 2025. These results are not intended as a verified study of the area. White Clay Creek was chosen merely to serve as an example of implementation. It has some interesting features, however. The eastern region of the basin displayed rampant suburbanization during the 1990s and the presence of a natural preserve area can be seen by the forested areas in the west. More information about the basin can be found in the US Department of the Interior's White Clay Creek Watershed Management Plan (White Clay Creek Wild and Scenic River Study Task Force, 1998).

On the left is the 1996 surface temperature image (tstar) in gif format for this same area. On the right is the image for the predicted temperature field in 2025. Note that the output from the climate module is at 1-km resolution, while the original land use maps (above) are at 25 meter. To generate this output, the climate module was run with the "high impact" option for the form of development. These images have been scaled such that, in both, white would represent the maximum possible tstar value. Areas of warming can be seen where new development or "filling in" occurred - in northern regions and the east, for example. The climate module creates similar output for the vegetation (fr) and the surface moisture (etrn) variables. These images should be used in conjunction with the ascii files that contain the raw data. To generate the integer-based gif images, the tstar and etrn climate variables were multiplied by 100 and then all variables' values were truncated.

Some suggestions for application of the Climate module to the SLEUTH model output:

• The natural preserve area in the west was part of the excluded layer of the SLEUTH model, preventing it from becoming developed. This area could be stripped of its exclusion privileges and the impacts explored.
• The climate module could be re-run with different options for the form of development. The role vegetation plays in determining how development impacts the local microclimate could then be observed - especially for a particular parcel of land that is about to be developed.
• Climate layers could be generated for each year of the SLEUTH model output and a gif animation created.