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Powering The Planet Eventhough dismissing claims that fossil fuels will not be plentiful enough to supply our needs, he warned of the potentially catastrophic environmental consequences of relying on them too heavily. "The people who claim CO2 in the atmosphere doesn't contribute to global warming are the biggest gamblers and risk-takers you've ever met," he declared, adding: "If I'm wrong, I'm a safe bet - just one more crazy MIT professor, and believe me there are plenty". Professor Nocera's area of research, and one he believes holds enormous long-term potential for energy creation, is solar power. If photosynthesis can be duplicated outside the leaf, he explained, the sun's energy can be harnessed as a fuel. The combination of water and light from the sun can be used to produce hydrogen and oxygen. The hydrogen can then be combined with the oxygen in a fuel cell to give back water and energy. There is, however, a catch. Admitting that our scientific know-how is still not advanced enough to enable this technique, he warned his audience: "If you want to buy into me, it will be the worst investment you've ever made in your lives"......... Posted by: Sarah Permalink January 28, 2006, 4:36 PM CT Cold Decembers often are followed by warm Januarys Early December temperatures indicated that it could be the sixth-coldest Indiana December in 110 years of recordkeeping, said Indiana State Climatologist Dev Niyogi, a Purdue assistant professor of agronomy and earth and atmospheric sciences. Warming during the last 10 days of the month, however, eliminated this possibility and led into a January thaw, which is something that happens as often as 65 percent of the time in the state following a subnormal December. "A January thaw exists when maximum temperatures are at least 6 to 10 degrees above the local normal maximum temperature for at least seven consecutive days," Niyogi said. "Of course, the normal maximum temperature will vary somewhat from north to south across Indiana, so we used 40 degrees or higher as our basis for estimating a thaw". Niyogi and Kenneth Scheeringa, a Purdue professional meteorology assistant and associate state climatologist, studied the years 1981 through 2005 to determine the frequency of January thaws. They found that such mid-winter temperature patterns occur most often in far southwestern Indiana at a rate of about 30 percent. In central Indiana, the rate is about 15 percent, while in north central Indiana it's about 8 percent......... Posted by: Tyler Permalink January 26, 2006, 12:01 AM CT A Look Deep Into The Centre Of The Earth Plumes are hot, narrow currents that well up in the mantle and which are responsible for the formation of long chains of volcanoes such as those of the Hawaiian Islands. The question of whether plumes rise from the boundary between the core of the Earth and the mantle that surrounds it, or from a much shallower boundary layer within the mantle, has been hotly debated for more than a quarter of a century. The new research proved the presence of material from the Earth's core by using a new type of mass spectrometer to analyse the isotope signature of the element thallium in Hawaiian volcanic rocks. Isotope analysis can reveal the physical, chemical and biological processes to which a single element has been subjected. Dr Mark Rehkamper , from Imperial College London's Department of Earth Sciences and Engineering and the senior author of the research, said: "It is only recently that researchers have developed the ability to analyse these volcanic rocks in enough detail to reveal exactly where in the Earth's interior they came from. The prior evidence has unfortunately been quite ambiguous but our new thallium isotope results are now able to conclusively rule out some of the alternative models. What remains is clear evidence of interaction between the Earth's core and mantle"......... Posted by: Tyler Permalink January 20, 2006, 6:39 AM CT Sensors for Environmental Observatories "In situ," or in place, sensors are producing a revolution in our understanding of the environment, as per the new National Science Foundation (NSF) report, Sensors for Environmental Observatories. Sensors, the report states, will enable a deeper and broader understanding of Earth's environment. Better-informed public policies that address the interactions between human society and the natural environment will be the result. Environmental scientists, with the support of NSF and other agencies, have in recent years designed and begun to implement several new environmental observing systems, including EarthScope, the National Ecological Observatory Network (NEON), the Ocean Observatories Initiative (OOI), and others. "These efforts will enable much-needed longer-term sensing of the environment," said Margaret Leinen, NSF assistant director for geosciences. "However, there are significant limitations to current sensor technology and the networks that collect data from them". To track changing conditions in deserts, forests, oceans or the atmosphere, environmental sensors must, like the postman, deliver information through snow, sleet, rain, and dark of night......... Posted by: Tyler Permalink January 18, 2006, 8:38 PM CT More Carbon From High Arctic Soil Ronald Sletten begins excavating a pit at a spot near Thule Air Base in Greenland as Jennifer Horwath examines the soil.A three-year study of soils in northwest Greenland found that a key prior study greatly underestimated the organic carbon stored in the soil. That's because the earlier work generally looked only at the top 10 inches of soil, said Jennifer Horwath, a UW doctoral student in Earth and space sciences. The earlier work, reported in 1992, estimated nearly 1 billion metric tons of organic carbon was contained in the soil of the polar semidesert, a 623,000-square-mile treeless Arctic region that is 20 percent to 80 percent covered by grasses, shrubs and other small plants. That research also estimated about 17 million metric tons of carbon was sequestered in the soil of the adjacent polar desert, a 525,000-square-mile area where only 10 percent or less of the landscape is plant covered. Horwath dug substantially deeper, in some instances more than 3 feet down, and found significantly more carbon. She concluded that the polar semidesert contains more than 8.7 billion metric tons of carbon, and the polar desert contains more than 2.1 billion metric tons......... Posted by: Tyler Permalink January 16, 2006, 10:40 PM CT Greenland Melting Faster In an update to findings published in the journal Geophysical Research Letters, a team led by Dr. Isabella Velicogna of the University of Colorado, Boulder, found that Greenland's ice sheet decreased by 162 (plus or minus 22) cubic kilometers a year between 2002 and 2005. This is higher than all previously published estimates, and it represents a change of about 0.4 millimeters (.016 inches) per year to global sea level rise. "Greenland hosts the largest reservoir of freshwater in the northern hemisphere, and any substantial changes in the mass of its ice sheet will affect global sea level, ocean circulation and climate," said Velicogna. "These results demonstrate Grace's ability to measure monthly mass changes for an entire ice sheet - a breakthrough in our ability to monitor such changes." Other recent Grace-related research includes measurements of seasonal changes in the Antarctic Circumpolar Current, Earth's strongest ocean current system and a very significant force in global climate change. The Grace science team borrowed techniques from meteorologists who use atmospheric pressure to estimate winds. The team used Grace to estimate seasonal differences in ocean bottom pressure in order to estimate the intensity of the deep currents that move dense, cold water away from the Antarctic. This is the first study of seasonal variability along the full length of the Antarctic Circumpolar Current, which links the Atlantic, Pacific and Indian Oceans......... Posted by: Tyler Permalink January 16, 2006, 10:36 PM CT Improving Pollution And forecasting Climate Launched in 2004, Aura helps researchers understand how atmospheric composition affects and responds to Earth's changing climate. The satellite works to reveal the processes that connect local and global air quality, and also tracks the extent Earth's protective ozone layer is recovering. The satellite is one in an international fleet of Earth-observing satellites nicknamed the "A-Train" that monitor the planet's atmosphere. "Aura is offering us a whole new way of looking at how pollution travels around the Earth, and precisely what the sources are," said Mark Schoeberl, project scientist for Aura at NASA's Goddard Space Flight Center, Greenbelt, Md. "The better we understand the origins of pollution, the more public health stands to benefit, across borders"......... Posted by: Tyler Permalink January 15, 2006, 8:13 PM CT Record-breaking Weather In 2005 "October 2005 was by far the wettest month in the last 57 years that the Lab has been keeping weather statistics, with almost double the amount of rain recorded in any October, and easily beating the prior monthly 13.01 inches of record rain in January 1979," said Victor Cassella, a Brookhaven Lab meteorologist. "We received 17.23 inches of rain in five consecutive days, from October 10 to 15, with 9 inches on October 14. Only in 1954, when Hurricane Edna dumped 9.02 inches of rain, did we get more than that amount of rain in one day". Cassella said the 2004-2005 snow season brought 78.5 inches of snow, the second snowiest season ever recorded. In the 1995-1996 season, 90.8 inches of snowfall was recorded at the Lab. But 2005 was the third consecutive year of more than 60 inches of snowfall, a pattern that has never been seen previously in the Lab's records. The average yearly snowfall in the area is 31.2 inches......... Posted by: Tyler Permalink January 13, 2006, 6:08 PM CT Insights Into Climate Changes Glacier fluctuations are sensitive indicators of past climate change, yet little is known about glacier activity in Pacific North America during the first millennium A.D. Alberto Reyes, a PhD student in the Department of Earth and Atmospheric Sciences, and his research team have found evidence for a regionally extensive glacier expansion during that time, suggesting that climate during the last several thousand years may have been more variable than previously thought. The research appears in the journal Geology. Reyes and his collaborators - mainly Dr. Dan Smith from the University of Victoria and Dr. Greg Wiles from the College of Wooster in Ohio - looked for a variety of clues in the field to help figure out the timing of past glacier fluctuations. At almost all of the glaciers studied, surface evidence previous to the "Little Ice Age" had been destroyed because glacial advance during that time had been so dramatic. Most of the evidence they found was in the form of buried soils and logs covered by glacial sediments. "In some cases, entire forest stands were buried by sediments, and their trunks sheared off by advancing ice," said Reyes, who initiated the work while a master's student at Simon Fraser University......... Posted by: Tyler Permalink January 11, 2006, 8:25 PM CT Prelude to an Earthquake? After sifting through seismic data from the two quakes, Valeri Korneev found a spike in the number of micro-earthquakes followed by a period of relative calm in the crust surrounding the quakes' epicenters - months before the quakes occurred. Eventhough more work needs to be conducted to determine whether other large quakes are foreshadowed by a similar rise and subsequent decline in small-magnitude tremors, Korneev's analysis suggests that these peaks may be indicative of the total set of geological stresses that affect the timing and location of large earthquakes. Understanding this total stress picture may eventually make it possible to predict destructive earthquakes within a much shorter time frame than currently possible. "Peaks in seismic activity in the crust surrounding a fault could help signal the arrival of large earthquakes," says Korneev of Berkeley Lab's Earth Sciences Division. "These peaks may be a good mid-term precursor and allow authorities to declare alerts several months before earthquakes"......... Posted by: Tyler Permalink |
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