Hannah Hoag

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  • Using technology to find hidden graves

    Using technology to find hidden graves

    DISCOVER

    One morning in July 2005, Amy Mundorff rode into the Bosnian countryside, tagging along with a team from the International Commission on Missing Persons. The roads wound past forests, farmland and villages. The group stopped near a filed in a hilly area on the outskirts of a village to meet an informant. From the gestures and the translator’s comments, Mundorff understood that the ground beneath the field might hold bodies.

    The war in Bosnia-Herzegovina had ended 10 years earlier, but thousands of people remained missing, many presumed buried in hidden graves scattered across the country. Mundorff, a forensic anthropologist wanted to learn how the team excavated and exhumed graves, and then sorted and identified the co-mingled human remains–her area of expertise.

    Backhoes scraped away the topsoil, peeling back the earth inches at a time. “they just dug and dug and dug,” recalls Mundorff. Once in a while, the machinery operators would stop and call over an investigator. “It was never anything human. There were roots, animal bones, rocks…but there were no graves,” says Mundorff. By the end of the day, the entire hillside had been dug up, and the team found nothing.

    Witness and survivor testimonies remain the most reliable way to locate hidden graves, but the approach is not foolproof. Many of the conflicts under investigation occurred years ago. Elderly witnesses may have fading memories that offer incomplete or incorrect accounts of atrocities. Sometimes the geography of a place changes. Roads get rerouted, forest are cleared, and the edges of villages expand.

    Mundorff knew from her own searches for buried murder victims in the United States that investigators often fail to locate hidden graves, but she didn’t expect it to be so difficult in Bosnia-Herzegovina: The country is smaller than Louisiana, and the whereabouts of 8,000 people remain unknown.

    “Even if we didn’t find that one grave, I thought we would find something because…where are they?” says Mundorff. She was disappointed and frustrated. “I thought, ‘God, there has to be something better out there.’”

    Keep reading this story in Discover.

  • Cities Beat the Heat

    Cities Beat the Heat

    Nature

    Rising temperatures are threatening urban areas, but efforts to cool them may not work as planned.

    The greenhouses that sprawl across the coastline of southeastern Spain are so bright that they gleam in satellite photos. Since the 1970s, farmers have been expanding this patchwork of buildings in Almería province to grow produce such as tomatoes, peppers and watermelons for export. To keep the plants from overheating in the summer, they paint the roofs with white lime to reflect the sunlight.

    That does more than just cool the crops. Over the past 30 years, the surrounding region has warmed by 1 °C, but the average air temperature in the greenhouse area has dropped by 0.7 °C. It’s an effect that cities around the world would like to mimic. As Earth’s climate changes over the coming decades, global warming will hit metropolitan areas especially hard because their buildings and pavements readily absorb sunlight and raise local temperatures, a phenomenon known as the urban heat island effect. Cities, as a result, stand a greater chance of extreme hot spells that can kill. “Heat-related deaths in the United States outpace — over the last 30 years — all other types of mortality from extreme weather causes,” says Kim Knowlton, a health scientist at Columbia University in New York. “This is not an issue that is going away.”

    Some cities hope to stave off that sizzling future. Many are planting trees and building parks, but they have focused the most attention on rooftops — vast areas of unused space that absorb heat from the Sun. In 2009, Toronto, Canada, became the first city in North America to adopt a green-roof policy. It requires new buildings above a certain size to be topped with plants in the hope that they will retain storm water and keep temperatures down. Los Angeles, California, mandated in 2014 that new and renovated homes install ‘cool roofs’ made of light-coloured materials that reflect sunlight. A French law approved in March calls for the rooftops of new buildings in commercial zones to be partially covered in plants or solar panels.

    But the rush to act is speeding ahead of the science. Although cool roofs and green roofs can strongly curb temperatures at the tops of buildings, they do not always yield benefits at the street level, and they may trigger unwanted effects, such as reducing rainfall in some places. “There was a notion that the community had reached a conclusion and there was a one-size-fits-all solution,” says Matei Georgescu, a sustainability scientist at Arizona State University in Tempe. “But that is not the case.”

    Keep reading in Nature …

  • The New Lice Wars

    The New Lice Wars

    Maclean’s

    Despite evidence that it’s time to abandon the no-nit rule requiring kids be sent home, schools have yet to get the message.

    When her three-year-old daughter was in daycare, Lisa got her first lice-alert telephone call. There were a slew of calls during senior kindergarten and more in Grade 1. The message was the same each time: Her daughter had nits in her hair and needed to be picked up. Lisa, who lives in Toronto, would postpone client meetings and collect her. “Thank God I work for myself. I have great clients,” says Lisa, who asked that her full name be withheld.

    The Toronto District School Board (TDSB) is one of the few school boards in Canada that sends kids home when head lice or their eggs, called nits, are discovered. Its no-nit policies require children to be free of nits before they return to school.

    These dreaded lice calls peak after school breaks—in September, January, and after the March break. Children pick up the bugs at sleepovers, camp, or on family vacations when they visit friends and relatives, and bring the hitchhikers to class.

    “There has been a concern about head lice in school for years, and the board developed a procedure for how best to deal with it,” says Chris Broadbent, the manager of health and safety at the TDSB. The policy, in place since January 2001, has been reviewed every few years, most recently, in May 2012. “We always look at the medical advice out there,” says Broadbent.

    But the current policy runs counter to the latest recommendations of the Canadian Paediatric Society (CPS). “We don’t think a no-nit policy makes any sense,” says Joan Robinson, a member of the Canadian Paediatric Society’s infectious disease and immunization committee. In 2008—and again in 2014—the CPS evaluated the available evidence on controlling nits and lice, and determined there was no medical rationale for excluding children from school because they had nits or lice. “Unless you inspect every child, every day, how do you know there isn’t a child in school who does have head lice?” asks Robinson. “It becomes discriminatory.”

    → Keep reading this story at Maclean’s

    “Male human head louse” by Gilles San Martin – originally posted to Flickr as Male human head louse. Licensed under CC BY-SA 2.0 via Commons – https://commons.wikimedia.org/wiki/File:Male_human_head_louse.jpg#/media/File:Male_human_head_louse.jpg

  • Greenland: A tale of fire and ice

    Greenland: A tale of fire and ice

    During the summer of 2012, fires exploded across the drought-stricken Colorado Front Range—a heavily populated area where the Great Plains meets the Rockies. One evening in early June, lightning struck a tree in the foothills west of Fort Collins. It ignited a fire that burned quietly for a few days and then rocketed downslope, fueled by a windstorm and bone-dry trees, dead from a mountain pine beetle infestation, and engulfed 30 square miles of forest in a single day.

    “This is the fire we always worried we might have,” Larimer County Sheriff Justin Smith had said at a news conference that night. The High Park fire grew to 136 square miles—four times the size of Manhattan. It was, at the time, the second-largest fire recorded in Colorado history.

    Jason Box, a glaciologist who grew up in Colorado, watched the disaster play out on television in the departure area at LaGuardia Airport in New York. “People were glued to the screens,” he says. Box, then a professor at the Ohio State University who now works for the Geological Survey of Denmark and Greenland, was waiting for a flight that would take him to Greenland for the 2012 field season to study the dynamics and melting of the Greenland ice sheet. He suddenly had a thought: Could soot from the wildfires melt Greenland’s ice sheet?

    Scientists have known for years that soot reduces the ability of snow and ice to reflect solar radiation back into space. They’ve found tiny black particles in the Arctic snow and ice that have come from the burning of fossil fuels, agricultural fields, trees, and grasslands thousands of miles away. Pure white snow is highly reflective—it has an albedo of 0.9, meaning it returns 90% of the solar energy that hits it. But snow that’s darker—say, if it is covered with soot—absorbs the sun’s energy, warming, melting and becoming even darker. It then absorbs more energy, launching a positive feedback cycle that causes local—and even regional—warming.

    If this cycle were to happen on a large scale in Greenland, it could spell trouble for the ice sheet, which holds 8% of the Earth’s freshwater and is suspended frozen atop the bedrock. If the ice sheet melted entirely, global sea levels would rise 23 feet. Yet even one foot—a plausible scenario that could play out within the next 35 years—would be enough to inundate millions of homes and send the cost of coastal damage from erosion, storm surges, and salt water encroachment soaring. Combined with the recent news that the West Antarctic ice sheet is already collapsing—which itself could release enough water to raise sea levels 13 feet—our descendants are likely looking at a very watery future.

    In Greenland that summer, Box tried to collect snow samples that would allow him to test his hypothesis, but launching a new project on the fly proved impossible. “I underestimated in the end how hard it would be to get those samples,” he says. “It was pretty discouraging.” But because any black carbon from the wildfires would get buried in subsequent snowfalls, he knew he had time. Or so he thought.

    .::. Keep reading this story at PBS’s NOVA Next.

  • Lady of the Lakes

    Lady of the Lakes

    Nature

    Diane Orihel set her PhD aside to lead a massive protest when Canada tried to shut down its unique Experimental Lakes Area.

    It was an ominous way to start the day. When she arrived at work on the morning of 17 May 2012, Diane Orihel ran into distraught colleagues. Staff from Canada’s Experimental Lakes Area had just been called to an emergency meeting at the Freshwater Institute in Winnipeg. “It can’t be good,” said one. (more…)