University Times

Have a few minutes before you have to punch the ol' time clock? Try calling up the Department of Geology and Planetary Science (GPS) web site at: www.geology.pitt.edu Whether you want to review the geological history of the Pittsburgh area or get the latest data on earthquakes and volcanoes or see some satellite pictures of your favorite planet, the GPS web site can get you there. The on-line vector/raster dynamic map serving link allows you to click on and zoom into maps of Moscow, Washington, D.C., and Pittsburgh, as well as world maps.

In addition to standard departmental information, such as academic programs, requirements, facilities and faculty, the GPS web site is linked to a whole host of scientific and entertaining sites.

Part of the reason for increasing the number of visuals on the web site is to tout the exploding field of geographic information systems (GIS), said William Harbert, who chairs the GPS department. "Really, it's an entirely new form of cartography. People think of maps as ways to get to the Turnpike, but you have to think of them now as visually referenced information systems, with much more potential."

Unlike traditional maps, which selectively emphasize topography or roads, for example, computer-scanned digitized maps can be combined with other digital map data to provide additional detail.

GIS applications integrate information types that can be referenced by geographic location, informing fields such as environmental science, resource management, geology, ecology, city and regional planning and civil engineering.

"Our particular niche is to have a demonstrated critical expertise in the increasingly important tool of GIS," Harbert said of his department, which offers an undergraduate certificate in GIS.

Recent news stories indicate that GIS data have been used in disaster relief efforts to pinpoint the most needy areas; such data also are being used in medicine, marketing and measuring. Layers of demographic data can be added to landscape maps and then analyzed to spot patterns and predict trends, in everything from the size and characteristics of an area's population to the number of bears in a national forest.

The companion discipline of remote sensing involves the enhancement and interpretation of data obtained from aircraft and satellite photographs. Appropriately enhanced, these data can provide positionally accurate information about land use patterns, natural hazards, vegetation health and geological conditions and can measure change over time. Even moving targets like oil spills can be mapped using remote sensing data.

Closer to home, GIS images are being used more and more by Pitt's Facilities Management team for compiling physical plant data. "You can measure how many buildings are within a designated distance with pinpoint accuracy," said Nicholas Contis, systems supervisor. He said that mosaics of fly-over images provide design blueprints for the entire campus infrastructure. "It has University-wide application and helps us do our job. You can cut part of the image out of the campus, superimpose it at the exact latitude and longitude on a fly-over image and study sewer lines, electric lines, water lines and other physical plant systems."

Some of the information would help with maintenance and repair decisions, he said. "Say, you find water leaks, and through these maps you recognize a trend that the leaks are all in a particular area. You may decide the appropriate action is to replace the large water main in that area, instead of dealing with the problem leak by leak."

GIS began in 1990 when the United States Geologic Survey, the U.S. Department of Agriculture's Natural Resource Conservation Service and Farm Service Agency proposed a national program to ensure the public domain availability of digital orthophoto quadrangle (DOQ) data.

DOQs are aerial photographs in digital form in which displacements caused by camera orientation and terrain have been removed. These products combine the image characteristics of a photograph with the geometric quality of a map and can be used in numerous GIS applications either alone or in combination with other digital data, such as digital line graphs or digital topographic maps called raster graphics.

Harbert recently provided a series of Pittsburgh fly-over digital images to the Carnegie Museum of Natural History's new Earth Theater, which produced a 20-minute piece called "The Millennium Show." The show whisks the audience through some of the major events of the geological history of the Earth, including the birth of the moon, the Ice Age, the Age of Dinosaurs and the formation of the continents and oceans.

Part of the show includes a Pittsburgh fly-over that was prepared by Pitt's GPS department.

According to Kerry Handron, director of the Earth Theater, "Bill Harbert gave these images to us as a way to bring us up to the present. Data tells us that all the rivers in this area used to run north. Now we get a contemporary, accurate look at the Three Rivers. Bill read the script I had written and matched the images to fit," Handron said.

The Earth Theater's Millennium Show is viewed at a 210-degree radius around the audience, with a 40-foot diameter screen viewed at audience level. More than 11,000 people have seen the show since the theater opened in December, Handron said.

"No tapes, no slides, no film," she said. "Only digitized images from a very large hard-drive." Handron says the images run at a speed of 30 per second.

Faster than the ol' time clock, anyway.

–Peter Hart

This is the first in an occasional series on interesting Web sites at Pitt. Suggestions on other Pitt sites are welcome. E-mail your suggestions to the University Times: utimes@pitt.edu