Ecologists now accept human beings and our activities as a significant influence on the Earths ecology. ASTER data is being used to better understand urban ecology, in particular how humans build their cities and affect the surrounding environment. Will Stefanov of Arizona State University will present the first set of ASTER images of the urban skeleton of the amount of built structures in 12 cities around the world and discuss the Urban Environmental Monitoring project which will examine 100 urban centers to look for common features (or lack of them) in global city structure and monitor change over time.

Ecologists now accept human beings and our activities as a significant influence on the Earths ecology. ASTER data is being used to better understand urban ecology, in particular how humans build their cities and affect the surrounding environment. Will Stefanov of Arizona State University will present the first set of ASTER images of the urban skeleton of the amount of built structures in 12 cities around the world and discuss the Urban Environmental Monitoring project which will examine 100 urban centers to look for common features (or lack of them) in global city structure and monitor change over time.

provides an online tour of residential, commercial, industrial, and religious locations spanning more than 2 centuries of history. Through maps, descriptions, and photographs of places both famous and little-known, the guide shows why residents and visitors have become so fond of Baltimore.

A flyby of the Washington-Baltimore corridor, from Landsat imagery draped over elevation data

Using data from different spacecraft and some powerful computer technology, visualizers at the Goddard Space Flight Center present you with a collection of American cities in a way you have never seen them before. Starting with our camera high above the Earth, we rush in towards the surface at what would be an impossible speed for any known vehicle. Passing though layers of atmosphere, the colors of our destinations shimmer with their own unique characteristics, and suddenly we find ourselves floating in virtual space just above the ground. This particular zoom also incorporates a fly through the clouds revealing the Terra-MODIS wonderglobe with clouds.

Here we see an image of the Washington,DC area taken with the Landsat satellite. The dates of the images are from 1986, 1990, 1996, 2000. For over 26 years, Landsat images have been used to help urban planners understand where growth is taking place and help geographers evaluate how different urban planning programs effect population growth and land use.

Here we see an image of the Washington,DC-Baltimore area taken with the Landsat satellite on March 27, 1998. For over 26 years, Landsat images have been used to help urban planners understand where growth is taking place and help geographers evaluate how different urban planning programs effect population growth and land use.

Here we see an image of the Baltimore-D.C. area taken with the Landsat satellite on March 27, 1998. For over 26 years, Landsat images have been used to help urban planners understand where growth is taking place and help geographers evaluate how different urban planning programs effect population growth and land use.

A special algorithm has been applied to the Landsat 7 image to illuminate the changes in low-density residential land use which exemplify sprawl. There is a link between impervious surfaces within a watershed, (here we see a subset of the Chesapeake Bay watershed area) and the water quality within the watershed. In general, once 10-15 % of an area is covered by impervious surfaces, increased sediments and chemical pollutants in runoff have a measurable effect on water quality. When 15-25% of a watershed is paved or impervious to drainage, increased runoff leads to reduced oxygen levels and impaired stream life. When more then 25% of surfaces are paved, many types of stream life die from the concentrated runoff and sediments. Red represents high concentrations of impervious surfaces. Blue represents moderate concentrations and green represents low concentrations of impervious surfaces.

A special algorithm has been applied to the Landsat 7 image to illuminate the changes in low-density residential land use which exemplify sprawl. There is a link between impervious surfaces within a watershed, (here we see a subset of the Chesapeake Bay watershed area) and the water quality within the watershed. In general, once 10-15 % of an area is covered by impervious surfaces, increased sediments and chemical pollutants in runoff have a measurable effect on water quality. When 15-25% of a watershed is paved or impervious to drainage, increased runoff leads to reduced oxygen levels and impaired stream life. When more then 25% of surfaces are paved, many types of stream life die from the concentrated runoff and sediments.