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Tibet Provides Passage For Chemicals
Learning how water vapor reaches the stratosphere can help improve climate prediction models. Similarly, understanding the pathways that ozone-depleting chemicals can take to reach the stratosphere is essential for understanding future threats to the ozone layer, which shields Earth from the sun's harmful ultraviolet rays. Scientists from the Georgia Institute of Technology, Atlanta; NASA's Jet Propulsion Laboratory, Pasadena, Calif.; and the University of Edinburgh, Scotland, performed their analysis using data from the Microwave Limb Sounder instrument on NASA's Aura spacecraft, combined with data from NASA's Aqua and Tropical Rainfall Measuring Missions. The team collected more than 1,000 measurements of high concentrations of water vapor in the stratosphere over the Tibetan Plateau and the Asian monsoon region. The measurements were collected during August 2004 and August 2005, during the height of monsoon season. Through the use of wind data and NASA atmospheric models, they found the water vapor originated over Tibet, just north of the Himalayan mountain range......... Posted by: Sarah Permalink Source Teamwork And Task Performance For The Moon And Mars
NEEMO-9 astronaut/aquanaut Nicole P. Stott and University of Cincinnati physician Tim Broderick perform survey and mapping activities to record the coordinates of landmarks of interest around Aquarius during an EVA.
Between daily living, telemedicine activities and moon-walking simulations, participants in the NASA Extreme Environment Mission Operations (NEEMO) 9 project helped National Space Biomedical Research Institute (NSBRI) scientists study performance ability, problem-solving and team cohesion issues that could affect long-duration space flights. "The NEEMO undersea mission is a similar experience in key ways to what future space travelers might encounter," said Dr. David Dinges, team leader of NSBRI's Neurobehavioral and Psychosocial Factors Team and principal investigator on the project. "Crew members live and work together in a small space, isolated from the outside world, and must effectively perform difficult tasks at a high level of alertness, both as individuals and a team." Clinician astronaut, Dr. Dave Williams of Canada, led the NEEMO undersea excursion in Aquarius off the Florida coast. Aquarius, the only underwater laboratory in the world, is owned and funded by the National Oceanic and Atmospheric Administration and operated by the University of North Carolina at Wilmington. Two additional astronauts, Nicole Stott and Ron Garan, and Dr. Tim Broderick, a doctor at the University of Cincinnati, rounded out the crew. Jim Buckley and Ross Hein of UNCW provided undersea engineering support......... Posted by: Brooke Permalink Source Ozone Recovering But Unlikely To Stabilize At previous Levels
The recovery is a result of the 1987 Montreal Protocol banning chlorine pollutants from the atmosphere, said Betsy Weatherhead, a researcher with the Cooperative Institute for Research in Environmental Sciences, a joint institute of CU-Boulder and the National Oceanic and Atmospheric Administration. But by the end of the century, ozone levels could be slightly higher or slightly lower than before 1980 because of high natural variability and human caused changes like warming temperatures, said Weatherhead. A paper by Weatherhead and Signe Bech Andersen of the Danish Meteorological Institute in Copenhagen is featured on the cover of the May 4 issue of Nature. "We now have some confidence that the ozone layer is responding to the decreases in chlorine levels in the atmosphere due to the leveling off and decrease of CFCs, and most of the improvements are in agreement with what we had hoped for with the Montreal Protocol in place," she said. "But we are not out of the woods yet, and the ozone recovery process still faces many uncertainties."........ Posted by: Tyler Permalink Source Man-made Climate Change
A new study published in this week's issue of Nature is the first to show that human activity is altering the circulation of the tropical atmosphere and ocean through global warming. Researchers widely agree that the climate has warmed over the past century and that human activities, such as burning fossil fuels, have significantly contributed to this global warming. This study tapped historical records that date back to the mid-19th century as well as simple theory and state-of-the-art computer model simulations to detect and attribute these climate changes. The conclusion was that the principal loop of winds that drives climate and ocean behavior across the tropical Pacific is slowing down and causing the climate to drift towards a more El Niño-like state. This could have important implications for the frequency and intensity of future El Niño events and biological productivity in tropical oceans. In their paper, titled "Weakening of Tropical Pacific Atmospheric Circulation Due to Anthropogenic Forcing," the scientists identify a 3.5 percent weakening that has occurred since the mid-1800s in this air system known as the Walker circulation. They also cite evidence that it may weaken another 10 percent by 2100. "There is an indication that the slowdown may be intensifying," said Dr. Gabriel A. Vecchi, lead author from NOAA's Geophysical Fluid Dynamics Laboratory. "The trend since World War II is larger than that over the entire record, and the long-term trend is larger than what is expected from natural climate variability. This is why we employed a very long observational record - to be able to accurately detect and attribute these changes."........ Posted by: Tyler Permalink Source Is A Russian Peninsula Really Part Of North America?
Caption: In this view of tectonic plate convergence between North America and Asia, the Kamchatka Peninsula lies on the Okhotsk block in the box at the center of the map. Credit: National Geophysical Data Center/Jody Bourgeois For a number of years geologists have harbored a belief that the Kamchatka Peninsula, shrouded in mystery and secrecy on Russia's east coast, actually sits on the same tectonic plate as the mainland United States, Canada and Mexico. The North America plate extends through Alaska across the Bering Strait and into Siberia, but the question is whether it reaches as far south as Kamchatka. The idea that the peninsula is part of the North America plate is perhaps a case of "tectonic imperialism" reinforced by a lack of evidence to the contrary, said Jody Bourgeois, a University of Washington Earth and space sciences professor who studies historic and prehistoric evidence of earthquakes and tsunamis. But new research of earthquakes and tsunamis along the Bering Sea coastline, including a magnitude 7.7 quake in 1969, suggests that Kamchatka sits atop a smaller plate called the Okhotsk block, which is being deformed in a sort of convergence zone of tectonic plates, Bourgeois said. Another magnitude 7.7 earthquake on April 21 bolsters the evidence, she said, and a magnitude 6.6 quake on April 29 also could help clarify the picture. The earthquakes last month were not widely reported because they did not produce widespread damage or fatalities on the sparsely populated peninsula, which separates the Okhotsk Sea on the west from the Bering Sea and North Pacific Ocean on the east......... Posted by: Tyler Permalink Source Students Help Cryosat-2 Arctic Campaign
"Having these students take part in CryoSat campaign activities is the result of a unique collaboration between ESA and the Climate Change College," said Malcolm Davidson, CryoSat Validation Manager. "The students will contribute to the fieldwork by taking and analysing snow and ice samples on the ground along side the UK researchers already in place. Not only will the students gain first-hand knowledge of how important scientific fieldwork is carried out, but they will also gain a deeper insight into the importance of ESA's CryoSat-2 mission to better monitor and understand environmental changes, in particular, changes in ice cover in the polar regions. It should prove a wonderful experience." The go-ahead to build and launch the CryoSat-2 mission came in February 2006 after the loss of the first CryoSat last October due to a launch failure. The mission's objectives remain the same as before - to measure ice thickness on both land and sea very precisely to provide conclusive proof as to whether there a trend towards diminishing polar ice cover, furthering our understanding of the relationship between ice and global climate......... Posted by: Tyler Permalink Source NASA Unlocks The Puzzle Of Global Air Quality
UNH research associate professor and atmospheric chemist Jack Dibb and research project engineer Eric Scheuer are currently on the jetliner among a select group of researchers taking part in NASA's Intercontinental Chemical Transport Experiment, or INTEX-B. This two-phase experiment is aimed at understanding the transport and transformation of gases and aerosols on transcontinental and intercontinental scales and assessing their impact on global air quality and climate. The first phase of INTEX-B kicked off in March when NASA, in collaboration with several other agencies and universities, quantified the outflow and evolution of gases and aerosols from Mexico City, one of the most heavily polluted "megacities" in the world. The current phase of INTEX-B is probing large, polluted air masses flowing off the Asian continent towards North America. The DC-8, in conjunction with a National Science Foundation-National Atmospheric Research Center C-130 research aircraft, is now plying the air above the Pacific Ocean measuring a wide range of pollutants. Because of meteorological conditions, this time of year is the peak outflow of Asian pollution toward the North American continent. Dibb says that already, with just three flights completed, they are seeing "pervasive" pollution throughout the North Pacific......... Posted by: Tyler Permalink Source Geoinformation from space sharpens population density maps
EO-STAT 'real-world population' distribution of Austria in 3D Credits: GeoVille
GeoVille, an Austrian company specialising in geo-information, and Tele Atlas, the largest manufacturer of road networks worldwide, are providing detailed models of areas based on road network information, statistical population data - supplied by the German-based market research institute GfK - and Earth observation (EO) images from ESA's Envisat, NASA's LANDSAT and the French Space Agency's SPOT satellites. Results are then integrated into Tele Atlas' digital geographic database, MultiNet, and can - among other applications - be used to spot the target groups for geomarketing campaigns. Geomarketing determines consumer profiles as per geographical zones based on market-specific data by using geographical information along with population and economic statistics. Companies can use this information to visualize the geographic location of potential target groups before implementing costly marketing campaigns and to envision future growth on a local or national scale. For instance, this information can be used to strategically choose a heavily-populated area in which to place a business in another country without ever placing a foot in the region......... Posted by: Tyler Permalink Source How does your city grow?
In addition to urban development patterns in Austin and San Antonio, this map illustrates that areas overlaying an aquifer, where it is possible to obtain drinking water by sinking a well, tend to see more scattered development than areas where drinking water necessarily comes from a connection to a public water system.
Matthew Turner and Diego Puga of the University of Toronto (Puga is currently a visiting professor at Universitat Pompeu Fabra), Marcy Burchfield of the Neptis Foundation, a Toronto-based organization focused on urban and regional research, and Henry Overman of the London School of Economics present their findings in the recent issue of The Quarterly Journal of Economics, in a paper entitled Causes of Sprawl: A Portrait from Space. Heavily illustrated with Geographic Information System images, the paper challenges conventional wisdom about urban sprawl and presents a vivid and detailed picture of land consumption in America's cities. Though urban sprawl is widely regarded as an important environmental and social problem, as per the authors, much of the debate over sprawl is based on speculation. The data to conduct detailed and systematic measurement of how and where land is converted to urban use has, until now, simply not been available. Despite widespread interest in the topic, "we know next to nothing about the extent to which development is scattered or compact, and how this varies across space," they write......... Posted by: Tyler Permalink Source Correlation Of Lithotectonic Units Across The Eastern Himalaya, Bhutan
Drill core recovered from the fan can potentially provide information on which parts of the mountains were eroding when, and how fast this was occurring over the past 17 million years. Until now, the interpretation of this core has been based solely on what is known about the bedrock eroded from the mountains by the Ganges and its tributaries, despite the fact that the Brahmaputra contributes most of the deposited sediment. The study of Richards et al. redresses this imbalance by examining the isotope geochemistry of bedrock in eastern Himalayan tributaries of the Brahmaputra, where the monsoon is most intense. These data, combined with the first published ages for the deposition of the sediments, allow the lithologies of Bhutan to be correlated westward. For the first time, the offshore record can now be properly interpreted for the entire Himalayan mountain range......... Posted by: Tyler Permalink Source |
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