• Picture disaster

    We’re all glued to the television in voyeuristic horror when disaster strikes, and there’s been plenty of incidents already this year to strike our imagination: a volcano in Iceland, an earthquake in Haiti, and the worst environmental disaster in U.S. history with the BP oil spill. You know what I’m talking about. Doesn’t this do something to you? The oil slick is headed right into a wildlife refuge. Well, how did past generations who didn’t have television or a camera depict those dramatic moments in living geologic history? Through art, of course. I don’t normally do book reviews, but since this is topical, it’s worth a mention. The Illustrated History of Natural Disasters was released recently, a book cataloging depictions of famous disasters from the antiquity to modern times. The images are largely from private collections, gathered by a pair

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  • The cold tongue

    The disappearance of glaciers goes hand in hand with warming temperatures. But it turns out that the process may be more complicated than rising CO2 levels in the atmosphere. For insight, we look to the past. The Pliocene epoch was last era in which temperatures were this warm, about 3 to 5 million years ago. CO2 concentrations were 30 percent higher, sea levels 15 to 20 meters higher, and temperatures more than 5 degrees Fahrenheit hotter. And there were no glaciers, except intermittent ice caps on Greenland. What kept the ice sheets at bay has been explored in a recent paper in the journal Paleoceanography by UC Berkeley geographer M. Vizcaíno and colleagues. The scientists believe that during the Pliocene, a permanent “El Niño state” may have been taking place. El Niño is a familiar climate pattern that occurs every

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  • Hot as France

    The European heat wave the summer of 2003 is still etched in many Europeans’ minds, and my own. I was having the time of my life hiking through rural, southern France at the time, but couldn’t figure out why I could barely make 7 miles before passing out on a picnic blanket. After finally reaching a town with a newspaper circular, I found out what everyone else already knew: it was damn hot — on the order of 105 degrees. I headed north, but Paris wasn’t any cooler. Whether or not this heat wave had anything directly to do with climate change — it was one of the hottest on record — it sure did raise awareness of how vulnerable we all are to the heat. About 40,000 people died as a result of seven unrelenting days of intense sunshine.

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  • This old lake

    Lake Tanganyika is the world’s longest lake and at 10 million years, one of the oldest. Straddling four countries in East and Central Africa, Tanganyika spans 418 miles and plunges 1,870 feet deep, making it an important source of freshwater and fish for millions of people. It so happens that its features also make it a geologic gold mine. Deep in these waters, researchers are finding out more about modern day climate change. Taking sediment cores from the bottom of the lake, Brown University researcher Jessica Tierney and her colleagues are finding the geological evidence that can give perspective on modern day observations of climate change. The lake has been getting warmer over the last century and in tandem there has been less mixing of surface water levels with the deeper ones. A drop in phytoplankton biomass – the lake’s

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  • The Big Freeze

    Around 12,000 years ago, the Earth spun into The Big Freeze, a (geologically) brief cold snap known as the Younger Dryas event. Glaciers returned to parts of the Northern Hemisphere and humans who were around then probably shivered quite a bit. The Clovis people in North American, the first paleo-Indian inhabitants that made distinctive bone and ivory tools, took a population nosedive. What caused The Big Freeze? The prevailing theory is a shutdown of the ocean conveyor belt caused by a rapid influx of fresh water from the melting of an immense glacial lake — Lake Agassiz — the used to cover much of Canada. Comets are also speculated culprits. But a New Mexico team of researchers is looking into an unusual contributing factor — a steep decline in large animal flatulence. It’s no secret that humans probably caused the

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  • Sizzling Hot

    Massive wildfires that cause untold destruction of life and habitat are becoming a feature of modern climate change. A mere 1.8 degree jump in temperature is predicted to equal a 40 percent increase in lightening, the main ignition source of natural fires. We already get some 8 million strikes a day under modern atmospheric conditions. It’s becoming sizzling hot here on Earth. New research into the past is backing up modern day observations. In a paper published in May in Nature Geoscienc, researchers at University College Dublin and colleagues tracked down climate and fire conditions from 200 million years ago during a major environmental transition period in Earth’s history – the Triassic-Jurassic boundary. During this period, massive volcanism broke apart the super-continent of Pangaea and spiked CO2 levels from 600 to more than 2,100 parts per million by volume. For

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  • Rebound

    Greenland’s coastal areas, rebounding like a sponge as the ice melts away, is rising upward about an inch a year. Geophysicists at the University of Miami found that if the trend continues, the acceleration could be as much as two inches per year by 2025. “It’s been known for several years that climate change is contributing to the melting of Greenland’s ice sheet,” said Tim Dixon, a co-author of a study published in the latest Nature Geoscience. “What’s surprising, and a bit worrisome, is that the ice is melting so fast that we can actually see the land uplift in response,” he said. “Even more surprising, the rise seems to be accelerating, implying that melting is accelerating.” Apparently, the same uplift of rocky surfaces is happening on the islands of Iceland and Svalbard. The research fits expectations of what happens

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  • Ice, ice baby

    Maybe the most defining characteristic of the Arctic is its ice. What would the Arctic be, if not for a frigid, barren, icy landscape? We’ve come to lament the loss of sea ice in the Arctic. Yet it’s interesting to note that the Arctic has, in fact, been ice free and for long periods of time. As recently as 125,000 years ago, the summertime brought ice-free conditions. In fact, it probably wasn’t until 14 million years ago — the launch of a cooling period — that the Arctic sea ice achieved any kind of perennial presence. Sea ice has varied by cycles of warm and cold, determined by Earth orbital patterns and other factors. Just 5,500 years ago — around the time of the first human writings — the Arctic ice became thick and “old,” the kind of ice we

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  • Reading the leaves

    We know there’s a relationship between rising levels of CO2 and warmer temperatures. That, of course, is the crux of global warming science and plays an important part in the models that predict future climate change. But looking at the past can be just as informative. A group of Penn State-led geoscientists and ecologists are shedding light on the matter by looking at the ecological conditions that lead to types of carbon in plants leaves. In a paper published in March 2010 in Proceedings of the National Academy of Science, the team reported a study involving 3,000 modern plants from diverse environments. They looked at two naturally-occurring carbon isotopes — carbon 12 and carbon 13 — in plant leaves to get a better sense of the environmental conditions in which they were growing. It turns out not just atmospheric carbon

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  • Lessons from the Ozone Hole

    Happy 25th anniversary, ozone hole. Maybe it’s bad juju to celebrate our environmental calamities, but in this case the discovery of a big hole letting in UV radiation over the Antarctic gave us a chance to respond before it was too late. The discovery itself, therefore, is worth celebrating, not least because it happened under bad odds. You’d think a big hole would be easy to see. But, in fact, up until a May 1985 article in the journal Nature, most scientists had been using satellite measurements of annual, global levels of ozone to show a relatively small drop of some 7 percent over a 60-year period. They knew chlorofluorocarbons and the like wrought havoc on stratospheric ozone, but the problem didn’t seem alarming. Then a team of scientists at the British Antarctic Survey looked at the data differently. Using

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