Into a fierce sky climbs the helium-filled balloon, wrapped in a red nylon hood to protect it from the sun. Under the balloon, a digital camera rides in a gondola, and under the basket, three hundred feet below, is a man with a neatly groomed beard wearing a baseball cap.
Michael Ramsey, Pitt assistant professor of geology and planetary science, is at the northeastern edge of Phoenix, where the city spills into one of the hottest deserts in America, the Sonoran. If he turns south, he will see a vista of tough soil, ancient cacti, dead grasses, and exposed bedrock, ending in the gray wall of the McDowell Mountains. If he turns north, hell find a few lonely subdivisions, brown and dusty.
But Ramsey, a camera remote control in one hand and a two-way radio in the other, looks neither north nor south, nor even toward the cloudless sky where the balloon is rising. Instead, he gazes steadily downward as his hiking boots stride forward, looking for signs.
At 6 a.m., when Ramsey and his team arrived in the desert and started work, the air temperature was 60 degrees. Now, at noon, the mercury reads 110 and is still rising. The team must wrap up its work for the day before the mercury spikes around 3 p.m. There is one good thing about the heat, though; it makes the rattlesnakes sluggish.
Ramsey dodges saguaro cacti and keeps pace with the balloons slow migration. Then, coming upon a massive cactus surrounded by a pile of glistening cinders, he stops short and talks into the radio: Heres a scar. I want to get a photo of this. Then, walk it a hundred meters south.
On a far ridge, Ramseys voice squawks from the box. His colleague, Ramon Arrowsmith, an associate professor of geological sciences at Arizona State University, is well beyond talking distance from Ramsey. He holds a large spool of nylon cord that serves as a leash for the tethered balloon. (It was Arrowsmith who designed the balloon-and-camera rig.)
Despite the oppressive heat, Arrowsmith wears long sleeves and pants to protect himself from thorny brush. Turning southward, he scrabbles sideways around a 12-foot cholla cactus, trying to tow the balloon in a straight line, tugging it against the desert wind.
Meanwhile, Ramsey follows beneath the balloon, swigging Gatorade every few yards. He presses a button on his remote control at measured intervals. High above, the digital camera dangling from the balloon clicks repeatedly, capturing the Arizona desert one image at a time.
Michael Ramsey first became interested in natural hazards while studying volcanoes. Indeed, volcanoes remain his main interest. His summer months are devoted to visiting active peaks like Mount Semeru in Indonesia, Mount Unzen in Japan, and Bezymianny in Russia.
Im not the kind of geologist who goes out and looks at mountain ranges that have been there for 100 million years, says Ramsey. I tend to look at things that are very quick, whether theyre fires, floods, volcanoes. And he adds, Were doing these kind of studies to save lives.
There are more hazards in the world than Ramsey himself can study. Many cities need geologists to evaluate the hazards that threaten their growth, and to feed this demand for what is best described as urban geologists, Ramsey (with funding from the Alfred P. Sloan Foundation) helped create and codirects a new graduate program at Pitt, a masters degree in Geographical Information Systems and Remote Sensing.
Its basically an MBA in science, Ramsey says. The program is intended for working professionals, and hence most of the classes take place at night. Students take courses in the geology department, of course, but also in such departments as mathematics and information science. They even take a sequence of courses offered by the law school and the Joseph M. Katz Graduate School of Business.
After graduating, these students will bring Ramseys techniques to environmental nonprofits and land management agencies around the country, many of which are struggling with problems similar to those in Phoenix.
Cities grow in different ways, which were documenting quantitatively now, Ramsey explains. He says city planners need to ask themselves what kind of impact urban growth will have on their cities not only today, but in 2010, in 2050. They need urban geologists to answer these kinds of questions:
If we run models forward, and we raise sea level, we raise temperatures, and we grow your city by another two million peoplehow does your infrastructure handle that? How does the air pollution change? What kind of natural hazards come into play?
Its Ramseys skill at studying hazards that led NASA to buy his Gatorade and gear and send him to the Sonoran in search of brushfire scars, some of which may be up to 30 years old. Ramseys project proposal was screened rigorously by other scientists and by NASA administrators before being accepted.
Its quite a review process and only the very best get funded, says John LaBrecque, director of NASAs Solid Earth and Natural Hazards Program, which sponsors Ramseys research.
The data from Ramseys desert research should help NASA identify visual patterns in hazards, which will make them recognizable from satellite photos. Even from a picture taken in space, it will be clear where something like a fire scar ends and a road begins. Once NASA perfects its software, based on Ramseys findings, satellite photos could help urban geologists worldwide better identify geological threats to development, things like brush fires, flooding, erosion, and land pollution.
In Phoenix, the concern is brush fires. Ramsey searches to find where they once occurred and could happen again. After his afternoon in the Sonoran, he prints and pieces together the photographs taken from the balloon, assembling a detailed montage of the desert far superior in its detail to any aerial or satellite photo. In the foreground, you can see the teams maroon Toyota pickup, gear lashed to the roof. And, just south, theres a curious bald patch in the midst of the scrubby desert.
Its not easy to find old brushfire scars. Even an expert like Ramsey must poke around carefully at the base of the plants, looking for cinders and charred stems. Its evident that an untrained eye would never find the scars left by brush fires from years, even decades past. With new vegetation now budding, the scars are invisible to developers planning subdivisions and cul de sacs.
For instance, the curious bald patch appearing in his desert photograph is much more than a patch. Its a huge fire scar, an area remarkably devoid of life, even for a desert. The scar came from the Rio fire, started by a lightning strike on July 7, 1995. The Rio fire seriously threatened the suburb of Fountain Hills, charring nearly 36 square miles before it was extinguished.
Ramsey and his team have mapped the exact parameters of the Rio fire, just as they have done with several neighboring fires: the Pinnacle fire of 1988; the Camp fire of 1994; the Dynamite fire of 1995. The preponderance of fires in an area smaller than Pittsburgh is alarming, even more so as new houses are built amid the fire scars.
Even a single brushfire poses a grave threat to the communities in its way. Three years ago, there was the blaze in Los Alamos, N.M. The fire, started as a prescribed burn, quickly slipped out of the control of forest rangers and galloped across the land. Twenty-five thousand people had to be evacuated, and 400 families were left homeless when their houses burned. The destruction didnt end once the Los Alamos fire was extinguished. Without the plants to hold the soil in place, a wave of topsoil washed downhill at the first rain, complicating the recovery effort.
Ramseys Sonoran photographs suggest that the desert developers are moving into harms way. The half-dozen fire scars in northeastern Phoenix suggest that future brush fires are distinctly possibleperhaps even likely.
The fire scars increase the chances of flooding and serious erosion. Phoenix only receives eight inches of rain per year, but much of it comes during the yearly monsoon of July and August. Often, the rocky soil cant absorb all the water at once, and the rain rapidly funnels into a few dry creek beds, sometimes creating flash floods of 15 feet in the span of an hour. The floodtides often carry with them the very land itself.
Scott Hunt, who oversees the Phoenix district for the Arizona State Land Department, knows the dangers well. Obviously, with all the building thats going on around Phoenix, it makes things more complicated, he says. Youre more likely to have a house in the way of a fire. If a fire got started in the desert 10 or 15 years ago, we didnt have to worry about it as much. Now, because of the new growth, we have to start worrying about it.
Phoenix was one of the fastest-growing cities in the United States during the 1980s, and people continue to relocate there at a rapid pace. Its a city without definite borders. From the air, the buildings of Phoenix look like they were scattered from an airplane and took root wherever they landed.
Phoenix has a huge problem, Ramsey says. Its got this megamachine pushing to build and build, and developers dont want to hear about hazards or fires. The average there is an acre an hour that is plowed down and built. Urban growth, Ramsey adds, isnt a problem unique to Phoenix. Its a problem cities struggle with worldwide.
Four hundred, thirty-eight miles above the earth, NASAs TERRA satellite swoops through its orbit like a great, reflector-winged bird. Its underbelly is studded with instruments, and one of these is a sealed box of gold foil containing a set of electronic cameras that peer at the earth, registering visible light, infrared, and thermal signatures. At 10:30 a.m. on the morning Ramsey trekked through the Sonoran, TERRA soared across the equator, peering at the Arizona landscape, at the dusty brown bloom of cacti and scrubs, at the harsh, empty tract where the Rio fire occurred. And it took pictures of it all.
As it rolled northward, TERRA beamed those images to the Land Processes Distributed Active Archive Center in Sioux Falls, S.D. The computers there, owned by NASA and the U.S. Geological Survey, received and stored the satellite images, so that when Ramsey flips on the lights in his Pittsburgh laboratory and sits down at his computer, he can summon up the Arizona desert with the click of his mouse.
At his workstation in Pittsburgh, Ramsey leans forward, looking at TERRAs images of northeast Phoenix. He identifies the very road he drove, the fire scars he photographed from the weather balloon. The satellite photos, though, have far less detail than those taken from his balloon. It takes Ramseys trained eye to find these landmarks.
His work with NASA is to develop a computer program that can spot the fire scars on its own, to develop programs that would compensate for the lesser resolution of a satellite orbiting at such a distant altitude. NASA could then point TERRA at any city on earth to help urban geologists identify potential geographical hazardslong before developers ever draw up blueprints.
Working with NASA satellites isnt the typical geologists work. Usually, geologists collect most of their data by hand, taking rock samples, measuring fissures, examining soils. Ramsey knows all these traditional tasksbut its the addition of satellites to his repertoire, and his interest in cities, that make him a new kind of geologist.
Its really a hybrid thing now, Ramsey says of his work. It doesnt fit anywhere.
In the next year, he will visit volcanoes on both sides of the Pacific, he will receive a new grant from NASA that will send him to Mali, West Africa, where the spreading Sahara is whipping up transatlantic dust storms, and he will use TERRA to map 100 of the worlds largest urban centers, cities like Houston and Miami; Addis Ababa, Ethiopia; and Dar es Salaam, Tanzania. Through the soaring eye of TERRA, Ramsey will look on as these cities stretch and grow, renewing themselves but also encountering dangers never before imagined.
Christopher Weber is a Pittsburgh-based freelance writer who is a student in the MFA program at the University.
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