Mar 10, 2010 • In an article titled “Modeling the human invader in the United States,” USGS scientists Thomas Stohlgren, Catherine Jarnevich, and Chandra Giri modeled humans as an “invasive species” as they “spread” in the conterminous U.S. from 1992 to 2001. Using the Landsat-derived National Land Cover Data (NLCD) together with a modeling program they mapped urbanization. (An area the size of Massachusetts was urbanized during the nine-year period studied and agricultural lands and forests were most likely to be urbanized.) The model, called Maxent, predicts species spread based on environmental factors. The authors used Maxent to model and map human spread from 1992 to 2001 and then compared it to the Landsat NLCD information. Using selected environmental variables (temperature, humidity, elevation, slope, geology) the model was 92.5 percent accurate. Based on their model results the authors concluded that humans have a highly predictable urbanization or “spread” pattern based on the environmental drivers of topography (elevation and slope) and climate (temperature and humidity).


Stohlgren, T., C. Jarnevich, and C. Giri (2010). Modeling the human invader in the United States. Journal of Applied Remote Sensing, vol. 4, 18 Feb. 2010