June 2002

• Assisted doctoral-level graduate work concerning landscape change in neotropical forests.

  GLCF greatly facilitates students' acquisition and analysis of remote-sensing data for several tropical regions. Since remote-sensing data was prohibitively expensive several years ago, scenes of the neotropics were unavailable to students. GLCF is now providing this data at little or no cost. For a recent doctoral dissertation, GLCF made available data that allowed a student to compare several regions of the neotropics in order to estimate rates of deforestation. Students interested in remote-sensing data for tropical regions also benefit from GLCF's data-sharing arrangements where GLCF offers scenes that are only available through EROS.

• GLCF attends the third international conference on urban remote sensing

  A paper was given regarding the growth of urban areas and using remotely sensed data to characterize contemporary growth patterns. This paper, "A Tale Of Two Cities: Characterizing Urban Growth Using Variable Resolution Remote Sensing Data" by Francis E. Lindsay, UMIACS, and Jeffrey G. Masek, NASA's Goddard Space Flight Center, was work sponsored in part by the Global Land Cover Facility. The paper was presented at the 3rd International Symposium on Urban Remote Sensing held in Istanbul, Turkey.

  The following is the abstract of the paper and presentation. The presentation is available from the Global Land Cover Facility.
  
  Satellite remote sensing offers considerable promise for examining the dynamics of urban growth, and relating observed patterns to basic principles of socio-economics. It is clear from past research that substantial variations exist in the rate at which North American cities have grown during the last several decades. These differences may relate to regional economic conditions, policy choices at the metropolitan level, or other physical geographic factors. Similarly, within individual cities, growth has not occurred in a spatially uniform manner, but is often more heavily concentrated in particular areas. In this paper we discuss the outcome of our research that compares urban growth and land-use efficiency between two very different metropolitan areas. We elucidate these differences by exploring varied urban centers namely Washington, D.C. and Portland, Oregon. Using Landsat and SPOT remote sensing data, we have mapped urban growth using a modified change-vector approach. Mapped rates of urban expansion since the 1970's appear to reflect economic conditions as well as land-use policy, and per capita growth rates (land-use efficiencies) range from 100 m2/person (Portland) to 400 m2/person (Washington).

  To evaluate these results quantitatively, we have created a GIS-based numerical model for urban growth that relies on economic placement theory, available land for development, population, and transportation convenience. The model results show graphically how individual decision-making cascades to form the complex urban patterns observed in the satellite data.

• Decline of Coastal Marshes in the Chesapeake and Delaware Bays

  Professor Michael Kearney of the University of Maryland Department of Geography recently published an article in EOS describing the loss of coastal marshes in the Chesapeake Bay watershed. These losses were measured in part through the use of GLCF-supplied Landsat imagery. The losses are associated with sea level rise in the eastern United States. The decline of coastal marshes represents a major collapse of a significant ecosystem and may also lead to major releases of carbon.

  Dr. Kearney's article received overwhelming local press coverage from publications including the Baltimore Sun, the Richmond Times-Dispatch, Scripps Howard News Service and Geotimes. Dr. Kearney also gave several radio and TV interviews on the subject.

  Click here to view a review published in the Geotimes.

  For further information on the subject of watersheds and our coastal wetlands, please see the GLCF web site. GIS and remote sensing data available from GLCF may be used to highlight those areas most needing remediation.

  Citation: "Landsat Imagery Shows Decline of Coastal Marshes in Chesapeake and Delaware Bays." Eos, volume 83, Number 16, pp. 173, 177-178, 16 April 2002.