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Increasing tornado outbreaks — Is climate change responsible?
Tornadoes and severe thunderstorms kill people and damage property every year. Estimated U.S. insured losses due to severe thunderstorms in the first half of 2016 were $8.5 billion. The largest U.S. impacts of tornadoes result from tornado outbreaks, sequences of tornadoes that occur in close succession. Last spring a research team led by Michael Tippett, associate professor of applied physics and applied mathematics at Columbia Engineering, published a study showing that the average number of tornadoes during outbreaks—large-scale weather events that can last one to three days and span huge regions—has risen since 1954. But they were not sure why.In a new paper, published December 1 in Science via First Release, the researchers looked at increasing trends in the severity of tornado outbreaks where they measured severity by the number of tornadoes per outbreak. They found that these trends are increasing fastest for the most extreme outbreaks. While they saw changes in meteorological quantities that are consistent with these upward trends, the meteorological trends were not the ones expected under climate change.
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U.S. record high temps could outpace record lows by 15 to 1 before century's end
If society continues to pump greenhouse gases into the atmosphere at the current rate, Americans later this century will have to endure, on average, about 15 daily maximum temperature records for every time that the mercury notches a record low, new research indicates.That ratio of record highs to record lows could also turn out to be much higher if the pace of emissions increases and produces even more warming, according to the study led by scientists at the National Center for Atmospheric Research (NCAR).
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A New Way to Image Solar Cells in 3-D
Next-generation solar cells made of super-thin films of semiconducting material hold promise because they’re relatively inexpensive and flexible enough to be applied just about anywhere.Researchers are working to dramatically increase the efficiency at which thin-film solar cells convert sunlight to electricity. But it’s a tough challenge, partly because a solar cell’s subsurface realm—where much of the energy-conversion action happens—is inaccessible to real-time, nondestructive imaging. It’s difficult to improve processes you can’t see.Now, scientists from the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have developed a way to use optical microscopy to map thin-film solar cells in 3-D as they absorb photons.
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Solar Cells Get Boost with Integration of Water-Splitting Catalyst onto Semiconductor
Scientists have found a way to engineer the atomic-scale chemical properties of a water-splitting catalyst for integration with a solar cell, and the result is a big boost to the stability and efficiency of artificial photosynthesis.Led by researchers at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), the project is described in a paper published this week in the journal Nature Materials.
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Can Radioactive Waste be Immobilized in Glass for Millions of Years?
How do you handle nuclear waste that will be radioactive for millions of years, keeping it from harming people and the environment?It isn’t easy, but Rutgers researcher Ashutosh Goel has discovered ways to immobilize such waste – the offshoot of decades of nuclear weapons production – in glass and ceramics.Goel, an assistant professor in the Department of Materials Science and Engineering, is the primary inventor of a new method to immobilize radioactive iodine in ceramics at room temperature. He’s also the principal investigator (PI) or co-PI for six glass-related research projects totaling $6.34 million in federal and private funding, with $3.335 million going to Rutgers.
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Super Emitters – are responsible for more than half of U.S. methane emissions
The bulk of methane emissions in the United States can be traced to a small number of “super emitting” natural gas wells, according to a new study.“We’re finding that when it comes to natural gas leaks, a 50/5 rule applies: That is, the largest 5 percent of leaks are typically responsible for more than 50 percent of the total volume of leakage,” said study co-author Adam Brandt, an assistant professor of energy resources engineering at Stanford’s School of Earth, Energy & Environmental Sciences.The findings, published online in the journal Environmental Science & Technology, could lead to more efficient strategies for sampling emissions and fixing the most significant leaks, said Brandt, who is also a senior fellow at Stanford’s Precourt Institute for Energy. By focusing on finding and fixing the biggest emitters, companies can significantly reduce the amount of methane leaking into the atmosphere.
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Soil management may help stabilize maize yield in the face of climate change
How will we feed our growing population in the face of an increasingly extreme climate? Many experts suggest the answer lies in breeding novel crop varieties that can withstand the increases in drought, heat, and extreme rainfall events predicted in the not-too-distant future. But breeding is only part of the equation, according to new research from the University of Illinois and several collaborating institutions across the Midwestern U.S."It might not be necessary to put all the stress of climate adaptation and mitigation on new varieties. Instead, if we can manage agroecosystems more appropriately, we can buffer some of the effects of climate instability," says U of I and USDA Agricultural Research Service ecologist Adam Davis.
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Increased ocean acidification is due to human activities, say scientists
Oceanographers from MIT and Woods Hole Oceanographic Institution report that the northeast Pacific Ocean has absorbed an increasing amount of anthropogenic carbon dioxide over the last decade, at a rate that mirrors the increase of carbon dioxide emissions pumped into the atmosphere.The scientists, led by graduate student Sophie Chu, in MIT's Department of Earth, Atmospheric, and Planetary Sciences, found that most of the anthropogenic carbon (carbon arising from human activity) in the northeast Pacific has lingered in the upper layers, changing the chemistry of the ocean as a result. In the past 10 years, the region's average pH has dropped by 0.002 pH units per year, leading to more acidic waters. The increased uptake in carbon dioxide has also decreased the availability of aragonite — an essential mineral for many marine species' shells.
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Detecting forest fragility with satellites
Over the past decades’ forests in different parts of the world have suffered sudden massive tree mortality. Now an international team of scientists led by researchers from Wageningen University in the Netherlands has found a way to spot from satellite images which forests may be most likely to fall prey to such die-off events.
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Climate change has less impact on drought than previously expected
As a multiyear drought grinds on in the Southwestern United States, many wonder about the impact of global climate change on more frequent and longer dry spells. As humans emit more carbon dioxide into the atmosphere, how will water supply for people, farms, and forests be affected?A new study from the University of California, Irvine and the University of Washington shows that water conserved by plants under high CO2 conditions compensates for much of the effect of warmer temperatures, retaining more water on land than predicted in commonly used drought assessments.According to the study published this week in the Proceedings of the National Academy of Sciences, the implications of plants needing less water with more CO2 in the environment changes assumptions of climate change impacts on agriculture, water resources, wildfire risk, and plant growth.