• Past warming one-tenth rate of modern day climate change

    Climate scientists find it useful to use analogs to put modern day change into historical perspective. No analog is more useful than the Palaeocene–Eocene Thermal Maximum, a period of rapid warming that occurred 56 million years ago when the continents were virtually in the same location as today. During the PETM, temperatures shot up 9 to 16 degrees Fahrenheit over a period of 20,000 years, a result of a massive release of carbon into the ocean and atmosphere. A new study out of Penn State University finds that carbon is now being released into the atmosphere at a rate 10 times as fast. The results, published in the current online edition of the journal Nature Geoscience, suggests major implications for today’s warming world. The PETM brought on ocean acidification, which likely caused a major disruptions to ecosystems, including the widespread

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  • Western weed offers glimpse into climate change

    Invasive species are fending very well under higher temperatures and carbon dioxide conditions. And the yellow starthistle in the American West offers a glimpse of why. A native to the Mediterranean, this thorny yellow-blossomed plant has become a bane to ranchers in the West as it outcompetes native grasses and degrades pasture quality. Cattle don’t want to eat it and it’s toxic to horses. A Purdue University study found that yellow star thistle has some of the greatest response to elevated carbon dioxide every observed, and that makes it a stronger competitor to native grassland species. It’s been able to grow a more effective root system and it’s taken advantage of extra water in the soil that other grassland species are not using. All this is bad news for Western farmers, who already contend with tens of millions of dollars

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  • Climate does cause earthquakes, but at speed of geologic time

    What does the earthquake in Japan have to do with climate change? Nothing, is the easiest response. Yet I’ve been hearing such leaps of association, tossed off like some conspiracy of nature against the human race. But just when you get comfortable with your own answers to life’s questions, out of nowhere hurls some sticky complication. An article published recently in the journal Earth and Planetary Science Letters backs up the idea that earthquakes and climate change are interrelated. I’ve come across some research before about pressure changes in glacial melt triggering earthquakes in the Arctic. But this new research out of The Australian National University takes place in India of all un-glaciated places. India is a place of frequent monsoons that dump copious rainfall along the eastern Himalayas. The monsoons  erode away the land and reduce its elevation, thereby

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  • Russian heat wave in 2010 not caused by climate change

    Last summer Russia suffered a debilitating heat wave, its hottest since 1880, making Russian officials for the first time into advocates for stemming climate change (Russia doesn’t have a great reputation on the topic). But alas, as much as it would help the climate change cause to link yet another heat wave to global temperature rise, a new study says that Russia experienced a fluke unrelated to the trend last year that made 2010 the hottest on record. Proving that not wacky weather event is climate change related, the study out of NOAA and the University of Colorado at Boulder found that natural variability produced the 62-day mercury spike that killed 11,000 people in Moscow, scorched 300,000 acres, and destroyed 1,500 homes. By using simulation modeling, the researchers found that the heat wave was the result of abnormal atmospheric patterns

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  • Study: scientists should stress known facts about climate change to public

    Why is it that as the science gets stronger around climate change, public belief gets weaker? It’s not just Americans who are becoming more and more unsure about whether scientists believe climate change is real. In mainland Europe and Britain, people are expressing more uncertainty in polls, according to a paper published in late March in the online journal Nature Climate Change. The public faith in science is still strong, as demonstrated by the way climate skeptics use science-like language to reject the conclusions of specific scientists, the study says. So what’s the problem? Nick Pidgeon of Cardiff University and Varuch Fischhoff of Carnegie Mellon University believe that scientists have difficulty explaining complicated physical processes in the face of countering efforts to box their statements into definitive claims. Take simulation modeling, which is getting more and more complex as new

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  • Stronger winds, bigger waves could be result of warmer ocean

    Surfers, kiteboarders, and other ocean joy-riders might be pleased with this latest bit of news. Wind speeds and wave heights have been increasing over the past quarter century, a result possibly linked to warmer waters caused by climate change. A study published last week in the journal Science states that wind speeds over the majority of the world’s oceans have increased by at least 0.25 percent to 0.5 percent per year, a cumulative increase of 5 to 10 percent over the last 20 years. That’s quite a bit of lift. Meanwhile, waves have jumped in height, but less significantly. The overall pattern is a higher growth in big, big waves, which makes sense since these kinds of waves tend to be generated by storms. Bigger storms, like hurricanes and cyclones, could be related to the ocean patterns and are long

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  • Under higher CO2 levels, plants take up more toxic materials

    Higher concentrations of CO2 in the atmosphere generally increase plant growth and productivity. Plants take up more nutrients from the soil. But according to a new study, they also take up more toxic materials from the soil. Benjamin Duval from the University of Illinois at Urbana-Champaign and colleagues showed in a paper published this month in the journal Environmental Science & Technology that contaminants in the soil become increasingly mobile in vegetation and that these toxins could be cycling faster through the ecosystem. “Plants can’t always distinguish toxic elements from nutrients,” Duval said in a review of his study published in Chemical & Engineering News. “For instance, arsenic can look a lot like phosphorous, which plants need for their metabolism.” Duval and company collected soil and oak tree samples from a site at the Kennedy Space Center in Florida run

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  • Rapid increases in greenhouse gases part of Earth’s history

    Rapid increases in greenhouse gases have happened more frequently in the Earth’s history than previously realized, according to a Scripps Institution of Oceanography-led study published last week in the journal Nature. Scientists have studied extensively the the Palaeocene-Eocene Thermal Maximum (PETM), about 56 million years ago, a period of rapid global warming that’s associated with a temperature spike on par with expectations for today’s global warming scenarios. But according to the Scripps Institute, there’s been a series of six smaller greenhouse gas fluxes during the same geologic time period (the Palaeocene and Eocene epochs, 65 to 34 million years ago). These so-called “modest hyperthermals” (meaning a rapid, pronounced period of global warming) had shorter durations and recoveries (about a 40,000 year cycle) and involved an exchange of carbon between surface reservoirs into the atmosphere and then into sediment. The researchers

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  • Earlier phytoplankton blooms in Arctic could affect food chain

    Tiny phytoplankton are taking to warmer Arctic waters by blooming almost two months earlier in the spring season. A new study published in the April edition of the journal Global Change Biology says that the earlier bloom has consequences for the Arctic food chain and carbon cycling. It may sound like a good thing. Phytoplankton, the nutritive basis for much of ocean life, stimulates the production of zooplankton, which provides forage for larval fish, and so on. But more of it out there, at an earlier point in the season, could be disrupting the food web. The researchers, led by Mati Kahru at the Scripps Institution of Oceanography at the University of California, San Diego, say there could develop a mismatch between the reproductive cycles of marine organisms. For example, shrimp may have adapted their egg hatching times to the

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  • Polar ice sheet melt largest source of sea level rise

    Melting ice sheets from Greenland and Antarctica has long been tied to rising sea levels. But these two sources are outpacing all others — including mountain glaciers and ice caps — t0 become the dominant feature in raising the seas, according to a new study slated for publication this month in the journal Geophysical Research Letters. Part of the reason for the significance of these polar ice sheets is that the rate of melt is accelerating. Researchers at the University of California, Irvine and colleagues found that the two sheets lost a combined average of 36.3 gigatonnes more than they did the previous year. Mountain glaciers and ice caps are melting too, but at a rate three times smaller than the ice sheets. “That ice sheets will dominate future sea level rise is not surprising — they hold a lot

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  • Antarctic ice sheet may be more durable than thought

    The stability of Antarctic ice has long concerned climate scientists. If the west Antarctic ice sheet’s base were to collapse, global sea levels could shoot up by five meters. But new research shows the ice could be a bit more tough than scientists thought. In a study published online last month in the geo-science journal Palaeogeograpy, Palaeoclimtology, Palaeoecology, University of Exeter-led geographer Christopher Fogwill and colleagues found that blue-ice moraines in West Antarctica fluctuated in thickness during the ups and downs of the Earth’s glacial cycles. But for at least the past 200,000 years, and maybe as long as 400,000 years, they remained intact, even during warm, interglacial periods. Moraines are a pile of rocks, often covered in ice in glaciated areas, that have been amassed by moving glaciers. The scientists analyzed the moraines in the Heritage mountain range near

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  • Sixth extinction almost here, but not quite

    Scientists define a mass extinction as when the Earth loses more than 75 percent of its species in short geological time, within 2 million years. This hasn’t happened very often — only five times in the last 540 million years. Is it happening now again? The “sixth extinction” has been discussed by biologists for decades. In a paper published this week in the journal Nature, University of California at Berkeley-led biologists take stock on the status of the the Earth’s current mass extinction. In comparing extinction rates in the past to the modern day, the researchers analyzed “extreme diversity loss.” By this they mean not just species dieing out, but the rate of die-out relative to the formation of new species. This rate of die-off is crucial because a species typically takes  hundreds of thousands of years or longer to

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  • Climate change could signal prolonged droughts in American Southwest

    Think the 1930s “Dust Bowl” was bad in the American West? Scientists have found evidence of “mega-drought” events that lasted centuries to millennia in the same region during warm, interglacial periods in the Pleistocene era (370,000-550,000 years ago). The evidence heightens concern over how the region will react to the modern day global temperature spikes. The American Southwest is already predicted to get pretty dry during climate change, due to a drop in winter precipitation that would increase evaporation rates and lead to smaller snow packs that normally provide water during the warmer months. Led by University of New Mexico earth scientist Peter Fawcett, the paper published in this week’s journal Nature discusses the discovery of extreme arid conditions in the Valles Caldera region of New Mexico during the warmest phases of interglacials, when the mean annual temperature was comparable

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  • A case for curbing near-term pollutants that worsen climate change

    Carbon dioxide is usually the greenhouse gas of choice in climate discussions, mainly because it’s long lasting, so the impacts of higher levels unfold over decades, if not centuries. But a new policy paper by the UNEP and World Meteorological Association shines light on the lesser discussed, more immediately potent molecules in the atmosphere: black carbon, and ground-level ozone. The paper states that if reduction measures were introduced on these other molecules (by 2030), future global warming could drop by nearly 1 degree Fahrenheit, enough to cut in half the potential increase in global warming by 2050. These companion molecules are emitted in the same way that CO2 gets into the atmosphere: combustion of fossil fuels. Black carbon is a heavy particle, the result of incomplete combustion of a fossil fuel or biomass like wood, that gets into the atmosphere

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  • Extreme precipitation events pinpointed to global warming

    Extreme precipitation events seem to be becoming more common in the Norther Hemisphere. But it’s been very hard for scientists to pinpoint a major weather event to global warming. Still, when a 100-year flood comes and then returns in a matter of a few years, it’s hard not to consider it a sign of a warming world. Several papers published this week in the journal Nature demonstrate that such extreme precipitation events in specific localities is the result of climate change and not an overactive imagination. The scientists studied the actual, observable precipitation patterns in the 20th century and then compared them to climate model simulations and a splash of probability to discover a close, predictive match up. They claim that their results provide “first formal identification of a human contribution to the observed intensification of extreme precipitation.” The scientists,

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