In a computer lab at the University of Alabama, Birmingham (UAB), anthropology professor Sarah Parcak scours satellite images for hidden Egyptian archaeological sites half a world away.
With the help of new technology that is revolutionizing research in such fields as archaeology, public health, and social science, Parcak and her collaborators are hoping to map the sites and explore them before urbanization and development destroy them.
In UAB’s new $150,000 lab, equipped with 10 computer workstations running a series of geographic information system and remote sensing programs, Parcak can travel the world, zooming in close enough to note the outlines of forgotten settlements, some buried beneath modern cities.
She has identified more than 100 previously unknown ancient sites, including a lost temple buried beneath agricultural fields, a major town in the East Nile Delta dating to the time of the pyramids, a large monastery from 400 A.D. in Middle Egypt, and a massive, largely buried city beneath a field on the East Delta dating to 600 B.C.
The far-ranging investigation uses eyes in the sky that can read not only visible light reflected from the earth, but other forms of reflected radiation, such as infrared and microwaves.
That view from the sky is matched up with on-the-ground investigations: traditional earth-digging archaeology in which spotted sites are excavated, dated, and mapped using GPS technology.
“This technology is changing the way we do archaeology,” said Parcak, who travels to Egypt two or three times a year working with her husband, Greg Mumford, who also teaches anthropology at UAB.
“The field of remote archaeology has advanced quite rapidly with the introduction of high-resolution satellite images,” she added.
Although the technology Parcak uses is much more advanced, she compares its use of high-resolution satellite images to Google Earth’s.
The satellites use infrared technology to “see” beneath modern towns and settlements.
“By manipulating the data on a variety of computer screens, you can make things appear that you wouldn’t see with your naked eye,” she said.
Parcak said she tested the technology on a modern settlement that she knew had an archaeological site underneath, to test its effectiveness. While the technology has a more difficult time seeing beneath the ground in very cultivated areas, it works very well in the desert, she said.
Parcak–whose work is the subject of a Discovery Channel special that will air later this school year–has been working with the technology for about six years.
The idea for the lab came out of Parcak’s undergraduate coursework at Yale, where she used similar technology and approaches. It got traction when she hired on at UAB and talked to her former dean, Tennant McWilliams, about the concept. McWilliams and Parcak formed a partnership with Max Michael, the dean of UAB’s School of Public Health, to sponsor the Laboratory for Global Health Observation.
Public Health was interested in the power of satellite imagery for applications to modern-day disease, and Parcak is advising researchers there as they put the imagery to work.
With the satellite imagery, researchers can chart temperature variations to spot breeding grounds for malaria-carrying mosquitoes in East Africa.
Looking for particular chemical signatures in the imagery, they can detect pollutants in the soil and water in Sri Lanka.
Cases of West Nile virus can be mapped, and researchers can investigate their proximity to tire dumps, which seem to be a favorite breeding ground for the mosquito that carries the virus. Health disparities and disease outbreaks can be mapped, monitored, and better understood.
“It’s such a cool idea,” Michael said. “To me, the fun part of this is when you start making the connection between the technologies, the ideas just start coming. It was the best of the collaborative interactive spirit at UAB.”
Parcak’s research interest is not in the revered and well-studied monuments, such as the great temples of Giza or the Temple of Luxor.
“We’ve got a pretty good idea of how the upper 1 percent lived,” she said. Instead, she wants to know how and where the common folks lived.
Despite all the archaeological attention Egypt has received at the well-known sites, Parcak estimates that only 0.01 percent of the archaeological sites have been identified and studied for a civilization that spanned 6,000 years and covered a land mass of 387,000 square miles.
Parcak’s work has been focused on the flat flood plain of the Nile. That landscape is dotted with sandy mounds atop which people settled.
“Any time you see a significant change in elevation, you are going to find an archaeological site,” she said.
The satellite imagery is helping create a better understanding about how the Mediterranean coastline and the course of the Nile have changed through time and how settlements shifted accordingly.
Soils from ancient settlements are detectable because they have a higher organic content, which tends to retain more water. “Archaeological soils are chemically different than other soils,” Parcak said.
Besides her research, Parcak is teaching an intensive introductory class on the use of satellite remote sensing. Students are learning how satellites can be used in health as well as social science research.
According to Parcak, UAB’s investment in the remote sensing lab is paying off. Currently, the lab’s various research endeavors have produced grant applications that could bring in $1.7 million in external support.