Shifting sands in Navajoland

TEESTO, ARIZONA

Reservation, at the end of a solitary, sand-choked dirt road, geologist Margaret Hiza Redsteer climbs out of her dark blue government Jeep, taps lightly on a door, and waits. And waits.

When Mary Biggambler finally pokes her head around the door, it's with a hearty laugh. "Oh, it's you!" she says. "We thought it was a Jehovah's Witness!"

Hiza Redsteer reintroduces herself, and tells Mary and Mary's husband, Levi, that she's back to check on a nearby weather station. She'd also like to measure the movement of a large sand dune, which appeared behind the Biggambler house just last fall. "Yeah, the sands are really coming up," says Mary. Though today is calm and blisteringly clear, the wind has blown fiercely this spring, flinging sand into eyebrows and under doors. Every two weeks or so, the president of the reservation's Teesto chapter arrives at the Biggamblers' with a front-end loader and scoops sand from the road, clearing the way for the Head Start bus to pick up the couple's granddaughter.

The 15-foot-high, sheer-faced dune behind the house may cause something worse than a roadblock. One cubic yard of sand -- about a pickup truck's load -- weighs more than a ton, and the dune, if it continues on its course, will eventually crush the nearby corral, perhaps even the Biggamblers' home.

Hiza Redsteer chitchats with the couple for a few minutes, learning that Levi was once a bull- and bronco rider, and that he used to play basketball on the reservation with her ex-husband's father. She then climbs back into the Jeep, preparing to head through the sage and snakeweed on the ever-fainter track to the weather station. "That's right!" laughs Levi. "Go play in the sand!"

is a fickle landscape. In wet years, its plentiful sand dunes -- which together cover about one-third of the reservation, an area larger than New Jersey -- sprout flowers and grass, creating the best grazing ground for Navajo sheep and cattle. In dry times, when the greenery is far sparser, the dunes fly free, reddening the horizon and washing up against sandstone mesas and volcanic buttes.

When sand dunes move, they shake out trapped silt -- the fine, nutrient-rich particles that turn the dunes into grasslands. Without silt, dunes are mostly piles of quartz, able to support little but tumbleweeds and other invasive species. With the decade-plus-long current drought and the resulting dune movement working against good forage on the reservation, many ranchers have reduced their herds and must now import hay for the remaining animals -- a costly proposition for an already marginal enterprise, especially with hay at a steep $14 per bale. While the states of Arizona and New Mexico require the use of weed-free hay, the Navajo Nation does not, and the resulting weeds lengthen the odds against native dune-dwelling plant species already weakened by drought.

Older residents vividly remember the dry times of the '50s and '70s, when blowing sand was also an annoyance and an economic hardship. But the stories pale alongside those of the most recent drought: In 1996, an elderly Tuba City couple, veterans of the last half-century's droughts, started having problems with sand and dust around their house. By 1999, their house was buried. "When I heard that," says Hiza Redsteer, "I started wondering if the '90s drought was different."

Global climate change is making its mark on the reservation. Average temperatures are rising, spring is arriving earlier, and the once-reliable annual monsoon seems more fitful than in the past, sometimes fizzling out early or starting late. Even as researchers debate the long-term effects of global warming on the region's precipitation, a study of climate models published in the journal Science last year projected that the current drought could become "the new climatology of the American Southwest" in a matter of years or decades.

When Hiza Redsteer and Casey Thornbrugh, one of her students, studied the local climate and its effects on dune plants, they found that abnormally high spring temperatures, in particular, produced less healthy vegetation -- and, by implication, less stable dunes. So if the climate models are correct, and premature springs continue, the ground on the Navajo Reservation may shift with new and more destructive vigor.

"How do we reverse the process -- and can we reverse the process?" Hiza Redsteer asks. "If warm spring temperatures are a critical factor, we may be fighting an uphill battle."

are more than academic: The Navajo Reservation was once her home. She grew up in the tiny northern Wyoming town of Story, the daughter of a Crow father and white mother, and while she says that "every kid is a natural geologist," no one suggested science might be in her future. Instead, she moved to Colorado and became a silversmith, trained by a company eager to exploit the '70s craze for handmade Native American jewelry. There, she met and married Robert Redsteer, and moved south to his home, the Navajo Reservation, to raise sheep and corn. "I thought I was going to live out here, have my kids, and live happily ever after," she says.

But politics intervened. Because of the bitter, long-running land dispute between the Navajo and Hopi tribes, Hiza Redsteer, her husband, and their three small children were resettled in Flagstaff in 1986. "I tried getting a job with a high school diploma, but that didn't work very well," she says. While living on the reservation, Hiza Redsteer had noticed serious problems with the amount and quality of water available to her family and neighbors, and in Flagstaff she resolved to return to school to study environmental science, eventually settling on a major in geology at Northern Arizona University.

By the time she graduated, she and Redsteer had parted ways, leaving her a single mother. But scholarships took her to graduate work in Montana and then to Oregon, where she earned her Ph.D. in 1999. "I just kept going to school," she laughs. "I would think, 'There's no way I'm going to make it,' and then something or someone miraculous would happen, like Dave Love."

During her graduate research, Hiza Redsteer studied the same Yellowstone-area volcanic deposits that renowned Wyoming geologist David Love had pored over early in his career. The coincidence inspired Love, at 81, to take Hiza Redsteer on a horse-packing trip through the rocks he still remembered. "After that, every once in a while he'd call me up and say, 'How are you doing?' " remembers Hiza Redsteer. "I'd say 'Fine,' and then he'd say, 'No, how are you really doing?' I'd say, 'Well, I don't know if the electricity is going to be on next month,' and he'd say, 'How much is the bill?' -- and he'd send me the money, along with extra for pizza and gum for the kids." Her children, now in their 20s and 30s and settled in the Pacific Northwest, encouraged her to continue her studies. "If they hadn't wanted me to finish school, I never would have been able to do it," she says.

Hiza Redsteer had never considered returning to the Navajo Reservation, where jobs of any sort were scarce, and jobs for a geology Ph.D., she thought, were nonexistent. But in 2000, while she was working for the U.S. Geological Survey in Denver, a colleague plunked a pile of black-and-white photos on her desk. They showed the extensive sand dunes on the reservation south of Tuba City. Hiza Redsteer, who had been hearing firsthand reports from her colleagues on the various effects of global warming, knew that climate change could also be making its presence felt in the dunes.

She moved back to Flagstaff to join the local USGS office, and by 2004, she had secured federal funding for her Navajo Land Use Project, which includes mapping the overall geology of the reservation, studying its history of land use, and tracking the nature and causes of sand dune movement. The drought was already well under way when Hiza Redsteer began, but at first she didn't realize just how active the dunes had become. "We tried to map where the dunes were, using aerial photos, but by the time we finished one photo, the dunes had moved," she says. "We had to step back and rethink the whole idea."

Hiza Redsteer and her colleagues have since set up two weather stations on the reservation, one near the Biggambler house, along with 20 dust traps. Invented by a USGS scientist for work in the Mojave Desert, the dust traps -- $15 affairs constructed of angel-food cake pans filled with glass marbles -- are gathering part of a sophisticated dataset. The information Hiza Redsteer collects about weather conditions, soil moisture, and local sand movement will be linked to patterns of climate and land-use changes, forming a database she hopes will help predict where and when the dunes will move next.

Hiza Redsteer, her colleague, Lee Amoroso, and Teesto chapter president Virgil Nez mark the leading edge of the looming dune with lengths of rebar and orange flagging tape. The blush-orange sand is soft, almost creamy, its tiny grains of quartz and feldspar buffed smooth, and the rebar slides in easily under Nez's hammer. Nez, who's been interested in Hiza Redsteer's project from the start, is already too familiar with the costs of the current drought: Last summer, when local wells ran low, he trucked water for the chapter from Winslow, a daily round trip of more than 80 miles.

Measuring tape unrolling in her hand, Hiza Redsteer walks toward the house, sighting her path by the family's satellite dish. "Five hundred and eighty-two feet," she shouts back to Amoroso. In a few weeks, she'll be back to check on the dune's progress.

While Hiza Redsteer hears some concern about climate change in her conversations with tribal members, she says others assume the current drought is just like its predecessors, another dry spell to be endured. Part of the reason is that, here as everywhere, climate is far from the only visible force of change. "You can look at the landscape and say, 'Wow, the climate has really done a job here,' but it's not just climate," she says, "It's how people are living, what they do when it gets drier or wetter." Since cars became common on the reservation in the 1950s, the number of roads has multiplied, concentrating livestock and further destabilizing the ground. With money scarce for maintenance, dirt roads can quickly turn into impassable arroyos, requiring new roads and yet more changes to the land. But researchers rarely stay long enough to untangle these factors, says Hiza Redsteer. "Scientists come and go out here. They'll say, 'We're going to do this for you,' but then they'll walk away and publish their results in a journal, and no one knows what happened." Geologists, who in the past scoured the reservation for coal and uranium, sometimes meet with extra suspicion. So when her study began, Hiza Redsteer made a point of visiting the reservation's monthly chapter meetings, explaining her plans and describing how her results could aid the tribe.

This summer, a team of Chinese scientists with experience in the Gobi Desert plans to visit Hiza Redsteer and the reservation, bringing with them their techniques for protecting villages from sand dunes using bamboo structures and -- ironically -- sandbags. Though stopping or diverting the sand behind the Biggambler house may seem quixotic -- Amoroso compares it to "nailing Jell-O to a wall" -- Hiza Redsteer believes it's her duty to attempt it. "We don't want to only point out problems," she says. "We want to try and work out solutions."

Just days after Hiza Redsteer measured the sand dune, Nez reported that a ferocious windstorm almost buried their three-foot high markers, leaving only four inches of rebar sticking out of the sand. A few weeks later, in early June, the rebar was gone. The dune now stands at least three feet closer to the Biggambler house.

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