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GLOBE data overlayed with DMSP nighttime lights

GLOBE Data: Underlays maps of "fires" and "urbanization" to help plot human impact.

The GLOBE DEM is useful as a base map for plotting other information. Here are some examples, using data from the Defense Meteorological Satellite Program's Operational Linescan System.

OLS is being used at NGDC to develop a digital spatial data set of "stable lights"". These are lights that "tend to be on every night" and include human settlements, gas flares in petroleum fields (such as the Niger Delta and the interior of Algeria). One can consider both of these factors to be effects of human settlement or urbanization.

The Gallery of GLOBE Images shows several images of DMSP stable lights plotted on GLOBEal imagery. In this image, low levels of stable light intensity are shown in shades of blues (from dark to light). These could be considered small settlements, or fringe areas of larger settlements, or simply areas with relatively lower light intensity. High levels of stable light intensity are shown as oranges through reds. These might be the cores of larger settlements, more intense gas flaring, etc.

In addition, the DMSP Program at NGDC is attempting to monitor nighttime lights that are transient - or usually not on. Typical examples of such lights are wildfires. In Africa, farmers in some regions use burning to clear fields, as part of their preparation for the next season's planting. Lower levels of transient light intensity are shown above as "olive" (green-brown colors). Brighter shades of olive through brown-gold show greater intensities of transient lights.

Immediately below this text you will see a close-up of parts of West Africa. The Niger Delta can be seen as the most intense stable lights, followed by the cities of Lagos (Nigeria), Accra (Ghana) and Abidjan (Cote d'Ivoire) westward along the coast of the Gulf of Guinea.

high resolution image with urbanization and fires

A approximately 1.5km (1 arc-minute grid) high-resolution GLOBE image with urbanization and fires is also available. This image is big (over 3 megabytes) If you are on a slow internet connection, you may not want to load it. If you have a fast connection, you may still have to increase your memory allocation in your browser. [For example, in Netscape, go to Edit:Preferences:Advanced:Cache and increase memory cache, say, to 12000 (12 MB) and the disk cache to at least that size).