November 7, 2006, 4:55 AM CT

Measuring Natural Airglow In The Upper Atmosphere

The second of five Special Sensor Ultraviolet Limb Imager (SSULI) remote sensing instruments, developed by the Naval Research Laboratory, was launched on November 4, 2006 on board the DMSP F-17 satellite. SSULI is the first operational instrument of its kind and provides a new technique for remote sensing of the ionosphere and thermosphere from space. SSULI's measurements will provide scientific data supporting military and civil systems and will assist in predicting atmospheric drag effects on satellites and reentry vehicles.

A Boeing Delta 4 vehicle launched the Air Force's Defense Meteorological Satellite Program (DMSP) F-17 satellite and the SSULI sensor into low earth orbit from Vandenberg Air Force Base, California. SSULI will be powered on and start initial sensor checkout 30 days after launch.

"Characterization of the Earth's upper atmosphere and ionosphere is a critical goal for Department of Defense (DoD) and civilian users," said Andrew Nicholas, the SSULI Principal Investigator at NRL. He discussed the significance of the planned SSULI observations, saying, "The upper atmosphere affects a number of systems from global to tactical scales. These systems include GPS positioning, HF radio communications, satellite drag and orbit determination, and over-the-horizon radar. Both the neutral atmosphere and the ionosphere are driven by solar and geomagnetic forcing that occur on a number of timescales ranging from short (minute, hours) to medium (days to months) to long (years). Real-time global observations that yield altitude profiles of the ionosphere and neutral atmosphere, over an extended period of time (DMSP through the year 2016) will fill a critical need."........

Posted by: Brooke      Permalink         Source

November 6, 2006, 9:21 PM CT

Mars Science Laboratory Shakedown in the High Arctic

Members of the AMASE team (AMASE stands for Arctic Mars Analog Svalbard Expedition) last month completed their fourth field season on the Arctic island of Spitsbergen. They went to test out instruments similar to those that will fly on an upcoming mission to Mars, and to perform a field test of a prototype rover, Cliff-bot, that is capable of climbing up and down 80-degree slopes.

Spitsbergen is the largest island in the Norwegian Svalbard archipelago, which lies between the northern tip of Norway and the northern polar ice cap. It is an inviting destination for astrobiology scientists because it contains several Mars analog sites: geologic formations that resemble, in various ways, ones on Mars.

One such site contains Devonian-age redbeds, formed between 408 and 360 million years ago. Such red-rock formations are a familiar sight in the American southwest, eventhough there they are typically older. The redbeds in Svalbard, composed of rust-colored fluvial sandstones and mudstones, which contain the iron-bearing mineral hematite, are reminiscent of regions of layered terrain seen on Mars in images taken by orbiting spacecraft.

Svalbard's "blueberry site" was selected because sulfate-bearing sandstones there contain small spherical concretions similar to the "blueberries" found by NASA's Opportunity rover in Meridiani Planum. The martian concretions, which contain hematite, helped researchers confirm the former presence of liquid water on Mars. The Svalbard concretions do not contain hematite; they are rich in sulfate and carbonate minerals that also form in the presence of liquid water. Interestingly these concretions contain evidence of cryptoendolithic communities.........

Posted by: Tyler      Permalink         Source

November 6, 2006, 7:25 PM CT

Accurate Climate Change Predictions

Current climate change impact models that consider only one weather variable, such as increasing temperature, sometimes spawn unsubstantiated doomsday predictions, as per scientists at Purdue and North Carolina universities.

Climate change studies that assess the full range of interactions among temperature, radiation, precipitation and land use can better aid humans to prepare for extreme shifts in weather patterns, the researchers report in a special issue of the journal Global and Planetary Change.

Climate change impact models often don't consider whether shifting weather will allow for sustainable agriculture, said Dev Niyogi, corresponding author of the journal article and Purdue agronomy, and earth and atmospheric sciences assistant professor.

Niyogi's team looked at weather factor interactions and their impact on two different crop plants by using data for weather and field conditions that occurred in a year considered normal for the test area. By designing a study that changed many variables simultaneously, the scientists observed that the complex interactions of precipitation with other weather factors had the most impact on the overall health of crops and regional agricultural productivity. They concluded that lack of precipitation will have the most dramatic effect on living conditions in the future.........

Posted by: Tyler      Permalink         Source

November 1, 2006, 8:03 PM CT

Climate Change Tops Environmental Concerns

As per a recent MIT survey, Americans now rank climate change as the country's most pressing environmental problem--a dramatic shift from three years ago, when they ranked climate change sixth out of 10 environmental concerns.

Almost three-quarters of the respondents felt the government should do more to deal with global warming, and individuals were willing to spend their own money to help.

"While terrorism and the war in Iraq are the main issues of national concern, there's been a remarkable increase in the American public's recognition of global warming and their willingness to do something about it," said Stephen Ansolabehere, MIT's Elting R. Morison Professor of Political Science.

The survey results were released Oct. 31 at the seventh annual Carbon Sequestration Forum, an international meeting held at MIT that focuses on methods of capturing and storing emissions of carbon dioxide--a major contributor to climate change.

Ansolabehere's colleagues on the work are Howard Herzog, principal research engineer in MIT's Laboratory for Energy and the Environment (LFEE), LFEE research associates Thomas E. Curry and Mark de Figueiredo, and Professor David M. Reiner of the University of Cambridge.

The findings are a result of two surveys, the first administered in September 2003 and the follow-up in September 2006. Each survey included about 20 questions focusing on the environment, global warming and a variety of climate-change-mitigation technologies.........

Posted by: Tyler      Permalink         Source

October 31, 2006, 7:35 PM CT

Expect a Warmer, Wetter World this Century

Recent episodes of deadly heat in the United States and Europe, long dry spells across the U.S. West, and heavy bursts of rain and snow across much of North America and Eurasia hint at longer-term changes to come, as per a new study based on several of the world's most advanced climate models. Much of the world will face an enhanced risk of heat waves, intense precipitation, and other weather extremes, conclude researchers from the National Center for Atmospheric Research (NCAR), Texas Tech University, and Australia's Bureau of Meteorology Research Centre.

The new study, "Going to the Extremes," will appear in the recent issue of the journal Climatic Change.

A number of prior studies have looked at how average temperature or rainfall might change in the next century as greenhouse gases increase. However, the new research looks more specifically at how weather extremes could change.

"It's the extremes, not the averages, that cause the most damage to society and to a number of ecosystems," says NCAR scientist Claudia Tebaldi, lead author for the report. "We now have the first model-based consensus on how the risk of dangerous heat waves, intense rains, and other kinds of extreme weather will change in the next century".

The study is one of the first analyses to draw on extensive and sophisticated computer modeling recently carried out for the Intergovernmental Panel on Climate Change. The IPCC's next assessment report will be released early in 2007.........

Posted by: Tyler      Permalink         Source

October 27, 2006, 9:19 PM CT

How Oceans Emit Sulfur Into Atmosphere

Researchers have discovered a bacterial "switch gene" in two groups of microscopic plankton common in the oceans. The gene helps determine whether certain marine plankton convert a sulfur compound to one that rises into the atmosphere, where it can affect the earth's temperature, or remain in the sea, where it can be used as a nutrient.

"This new gene offers a powerful tool to study the question of how these plankton are involved with sulfur exchange between the ocean and atmosphere," said Mary Ann Moran, marine microbial ecologist at the University of Georgia. Moran and her colleagues published their findings in the Oct. 26, 2006, issue of the journal Science.

Much of the sulfur in the atmosphere comes from the surface of oceans, from a compound called dimethlysulfide, or DMS. Marine plankton control how much sulfur rises into the atmosphere by converting a compound called DMSP, or dimethylsulfoniopropionate, to DMS or to sulfur compounds that are not climatically active. Moran and her team discovered a gene that controls whether or not these sea drifters create DMS that rises into the air.

"Isolating and discovering a novel, keystone bacterium from the ocean first, and then sequencing its genome enabled this team to find the genes involved in the DMSP cycle," said Matthew Kane, program director in the National Science Foundation (NSF) Division of Molecular and Cellular Biosciences, which supported the research. "The research has revealed the previously hidden role that marine microbes play in the global sulfur cycle".........

Posted by: Sarah      Permalink         Source

October 26, 2006, 4:46 AM CT

World's Most Intense Thunderstorms

A summer thunderstorm often provides much-needed rainfall and heat wave relief, but others bring large hail, destructive winds, and tornadoes. Now with the help of NASA satellite data, researchers are gaining insight into the distribution of such storms around much of the world.

By using data from the NASA Tropical Rainfall Measuring Mission (TRMM) satellite, scientists identified the regions on Earth that experience the most intense thunderstorms. Their study was reported in the August 2006 issue of the Bulletin of the American Meteorological Society. The strongest storms were found to occur east of the Andes Mountains in Argentina, where warm, humid air often collides with cooler, drier air, similar to storms that form east of the Rockies in the United States. Surprisingly, some semi-arid regions have powerful storms, including the southern fringes of the Sahara, northern Australia, and parts of the Indian subcontinent. In contrast, rainy areas such as western Amazonia and Southeast Asia experience frequent storms, but relatively few are severe. Northern Pakistan, Bangladesh, and parts of Central Africa also experience intense thunderstorms.

"TRMM has given us the ability to extend local knowledge about storms to a near-global reach," said lead author Edward Zipser, University of Utah, Salt Lake City. "In addition to containing the only precipitation radar in space, TRMM's other instruments provide a powerful overlap of data that is extremely useful for studying storms".........

Posted by: Tyler      Permalink         Source

October 24, 2006, 8:23 PM CT

Soot from wood stoves impacts global warming

New measurements of soot produced by traditional cook stoves used in developing countries suggest that these stoves emit more harmful smoke particles and could have a much greater impact on global climate change than previously thought, as per a research studyscheduled to appear in the Nov. 1 issue of the American Chemical Society journal Environmental Science & Technology.

Perhaps as a number of as 400 million of these stoves, fueled by wood or crop residue, are used daily for cooking and heating by more than 2 billion people worldwide, as per the study's lead authors, Tami Bond, Ph.D., and doctoral candidate Chris Roden of the University of Illinois, Urbana-Champaign. In a field test in Honduras, the scientists observed that cook stoves there, which are similar to those used in other developing nations, produce two times more smoke particles than expected, based on prior laboratory studies. These dark, sooty particles, which are darker than those produced by grassland or forest fires, have a climate warming effect because they absorb solar energy and heat the atmosphere, as per Roden.

In earlier work, Bond estimated that burning firewood -- the principal fuel for cook stoves in the developing world -- produces 800,000 metric tons of soot worldwide each year. In comparison, diesel cars and trucks generate about 890,000 metric tons of soot annually. These two sources each account for about 10 percent of the soot emitted into the world's atmosphere each year, she said.........

Posted by: Tyler      Permalink         Source

October 24, 2006, 7:27 PM CT

New Theory For Mass Extinctions

A new theory on just what causes Earth's worst mass extinctions may help settle the endless scientific dust-up on the matter. Whether you favor meteor impacts, volcanic eruptions, cosmic rays, epidemics, or some other cause for the worst mass extinction events in Earth's history, no single cause has ever satisfied all researchers all the time for any extinction event. That may be because big extinctions aren't simple events.

The new Press/Pulse theory gets around the controversy by rejecting the all-or-nothing approach to mass extinction, calling instead on a combination of deadly sudden catastrophes - "pulses" - with longer, steadier pressures on species - "presses".

"What we wanted to do is move away from the idiosyncratic approach to extinction mechanisms and look for what these intervals had in common. If you have A and B you will get a mass extinction," said Ian West, a 2006 graduate of Hobart and William Smith Colleges in Geneva, NY.

West and Hobart and William Colleges paleontology professor Nan Crystal Arens are scheduled to present their work on the Press/Pulse theory on Wednesday, 25 October, at the Annual Meeting of the Geological Society of America in Philadelphia.

Using databases that chart genera of marine organisms and their extinctions through the fossil record, West and Arens divided the last 488 million years of geologic history into four groups: times of suspected impact events (Pulses), times of massive volcanic eruptions (Presses), times when neither Presses nor Pulses occurred, and times when Press and Pulse coincided. They compared average extinction rates in geologic stages in each of these groups.........

Posted by: William      Permalink         Source

October 22, 2006, 11:07 PM CT

Geological Feature Key To Finding Tombs

A 42-year-old method for finding water, monitoring pollution and helping with tunneling may also be a way to locate and protect tombs in the Valleys of the Kings and Queens and other burial sites in Egypt, as per Penn State researchers.

The idea that fracture traces could bare some connection to the rock cut tombs found in Egyptian valleys came to Katarin A. Parizek as she toured Egypt. K. Parizek, the daughter of Richard R. Parizek, professor of geology and geo-environmental engineering at Penn State, is a digital photographer, graphic designer and geologist. In 1992, on a Nile cruise to the Valley of the Kings near Luxor, she recognized the geological structures.

"A number of of the tombs were in zones of fracture concentration revealed by fracture traces and lineaments," says K. Parizek, an instructor in digital photography. "I knew that these fractures were what Dad used to find water or to plan dewatering projects."

Fracture traces are the above-ground indication of underlying zones of rock fracture concentrations. In 1964, Laurence H. Lattman and R. Parizek published a paper on fracture traces that indicated where increased weathering and permeability occurred and where people could drill wells more efficiently. These fracture traces can be between 5 and 40 feet wide, but average about 20 feet, and can be as long as a mile.........

Posted by: William      Permalink         Source