Tag Archives: atmosphere

UF Study Shows Tundra Fires Could Accelerate Climate Warming

By Guest PostJuly 31, 2011Environmentanaktuvuk river fire, arctic carbon cycle, arctic fires, arctic tundra, atmosphere, atmospheric carbon dioxide, canada, carbon, city of miami, ecologist, ecosystem ecology, global climate, global climate warming, greenhouse gases, michelle mack, Nature, north slope of alaska brooks range, organic matter, permafrost, radiocarbon dating, russia, smoke, soil bound carbon, ted schuur, terry chapin, tundra, university of alaska, university of florida, wildfires

GAINESVILLE, Fla. — After a 10,000-year absence, wildfires have returned to the Arctic tundra, and a University of Florida study shows that their impact could extend far beyond the areas blackened by flames.

In a study published in the July 28 issue of the journal Nature, UF ecologist Michelle Mack and a team of scientists including fellow UF ecologist Ted Schuur quantified the amount of soil-bound carbon released into the atmosphere in the 2007 Anaktuvuk River fire, which covered more than 400 square miles on the North Slope of Alaska’s Brooks Range. The 2.1 million metric tons of carbon released in the fire — roughly twice the amount of greenhouse gases put out by the city of Miami in a year — is significant enough to suggest that Arctic fires could impact the global climate, said Mack, an associate professor of ecosystem ecology in UF’s department of biology. (more…)

Rising Oceans – Too Late to Turn the Tide?

By Guest PostJuly 16, 2011Environmentantarctic ice sheets, anthropogenic reasons, atmosphere, atmosphere ocean interactions, bahamas, barbados, bette otto bliesner, cause and effect relationships, climate, climate models, computer simulations, current global warming, earth, global distribution of sea surface temperatures, great polar ice sheets, greenhouse gas concentrations, greenhouse gases, greenland, ice caps, jonathan overpeck, last interglacial period, melting ice sheets, mountain glaciers, natural reasons, nicholas mckay, paleoceanic records, paleoclimate, rising sea levels, sea level, thermal expansion of seawater, thermal expansion of warming ocean waters, university of arizona

*Melting ice sheets contributed much more to rising sea levels than thermal expansion of warming ocean waters during the Last Interglacial Period, a UA-led team of researchers has found. The results further suggest that ocean levels continue to rise long after warming of the atmosphere levels off.*

Thermal expansion of seawater contributed only slightly to rising sea levels compared to melting ice sheets during the Last Interglacial Period, a University of Arizona-led team of researchers has found.

The study combined paleoclimate records with computer simulations of atmosphere-ocean interactions and the team’s co-authored paper is accepted for publication in Geophysical Research Letters. (more…)

Mars: Red Planet’s Rapid Formation Explains Its Small Size Relative to Earth

By Guest PostMay 27, 2011Scienceali pourmand, atmosphere, chemical behavior, chondrites, composition of chondrites, computer simulation, dauphas and pourmand, earth, embryos, enriqueta barrera, fine scale chronology, geophysicist, hafnium, lithophile elements, mantle of mars, mars, martian meteorites, national science foundation, nicolas dauphas, non volatile elements, nsf, radioactive decay, red planet, refractory, solar system, tungsten in meteorites, tungsten isotopic composition, university of chicago, xenon content

*Mars developed far more quickly than our blue planet*

Mars developed in as little as two to four million years after the birth of the solar system, far more quickly than Earth, according to results of a new study published in this week’s issue of the journal Nature.

The red planet’s rapid formation helps explain why it is so small, say the study’s co-authors, Nicolas Dauphas at the University of Chicago and Ali Pourmand at the University of Miami. (more…)

Scientists Discover Animal-like Urea Cycle in Tiny Diatoms in the Ocean

By Guest PostMay 19, 2011Sciencealisdair fernie, andrew allen, animal like urea cycle, atmosphere, carbon recycling, chris bowler, david garrison, deep ocean, diatoms, environmental health of marine ecosystems, genome, marine diatoms, metazoan, national science foundation, nsf, nutrient, nutrient metabolism in diatoms, pennate diatom, photosynthesis, phytoplankton, rna interference, silica, unique cell walls, urea synthesis

*Cycle enables marine phytoplankton to use carbon and nitrogen from their environment*

Scientists have discovered that marine diatoms, tiny phytoplankton abundant in the sea, have an animal-like urea cycle, and that this cycle enables the diatoms to efficiently use carbon and nitrogen from their environment. (more…)

NASA Mission Will Observe Earth’s Salty Seas

By Guest PostMay 18, 2011Scienceaquarius, aquarius sac d observatory, Argentina, atmosphere, california, climate, comision nacional de actividades espaciales, conae, conveyor belt, deep ocean, delta ii rocket, earth climate, gary lagerloef, melting of sea ice, NASA, ocean circulation, ocean surface salinity, polar regions, radiometer, river runoff, salinity, salinity variations, seattle, space agency, vandenberg air force base, water cycle

PASADENA, Calif. – Final preparations are under way for the June 9 launch of the international Aquarius/SAC-D observatory. The mission’s primary instrument, Aquarius, will study interactions between ocean circulation, the water cycle and climate by measuring ocean surface salinity.

Engineers at Vandenberg Air Force Base in California are performing final tests before mating Aquarius/SAC-D to its Delta II rocket. The mission is a collaboration between NASA and Argentina’s space agency, Comision Nacional de Actividades Espaciales (CONAE), with participation from Brazil, Canada, France and Italy. SAC stands for Satelite de Applicaciones Cientificas. Aquarius was built by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and the agency’s Goddard Space Flight Center in Greenbelt, Md. (more…)

NASA Orbiter Reveals Big Changes in Mars’ Atmosphere

By Guest PostApril 22, 2011Scienceatmosphere, dry ice, frozen carbon dioxide, greenhouse effect, lake superior, liquid water, mars, mars reconnaissance orbiter, martian carbon dioxide, martian dust storms, martian surface, NASA, red planet, roberto seu, roger phillips, south pole

PASADENA, Calif. — NASA’s Mars Reconnaissance Orbiter has discovered the total amount of atmosphere on Mars changes dramatically as the tilt of the planet’s axis varies. This process can affect the stability of liquid water, if it exists on the Martian surface, and increase the frequency and severity of Martian dust storms.

Researchers using the orbiter’s ground-penetrating radar identified a large, buried deposit of frozen carbon dioxide, or dry ice, at the Red Planet’s south pole. The scientists suspect that much of this carbon dioxide enters the planet’s atmosphere and swells the atmosphere’s mass when Mars’ tilt increases. The findings are published in this week’s issue of the journal Science. (more…)

‘Thawing Permafrost Likely Will Accelerate Global Warming in Coming Decades’

By Guest PostFebruary 18, 2011Environmentalaska, Arctic, atmosphere, carbon, carbon dioxide concentration, climate change, CO2, earth, environmental sciences, fossil fuel emissions, frozen in soil, greenhouse gases, industrial age, kevin schaefer, last glacial period, lori bruhwiler, noaa, permafrost, Siberia, tingjun zhang, warming temperatures

Up to two-thirds of Earth’s permafrost likely will disappear by 2200 as a result of warming temperatures, unleashing vast quantities of carbon into the atmosphere, says a new study by the University of Colorado Boulder’s Cooperative Institute for Research in Environmental Sciences.

The carbon resides in permanently frozen ground that is beginning to thaw in high latitudes from warming temperatures, which will impact not only the climate but also international strategies to reduce fossil fuel emissions, said CU-Boulder’s Kevin Schaefer, lead study author. “If we want to hit a target carbon dioxide concentration, then we have to reduce fossil fuel emissions that much lower than previously thought to account for this additional carbon from the permafrost,” he said. “Otherwise we will end up with a warmer Earth than we want.” (more…)

Ice Cores Yield Rich History of Climate Change

By Guest PostFebruary 4, 2011EnvironmentAntarctica, atmosphere, borehole, carbon dioxide, climate history, climate record, concentration of greenhouse gases, core, coring, earth, gases, human activity, ice, ice core, isotopic composition, julie palais, kendrick taylor, krypton, logging, russia, sample, temperature of the ocean, vostok station, wais, west antarctic ice sheet divide, xenon

*Research project completes drilling for the year, reaching two miles below West Antarctic Ice Sheet*

On Friday, Jan. 28 in Antarctica, a research team investigating the last 100,000 years of Earth’s climate history reached an important milestone completing the main ice core to a depth of 3,331 meters (10,928 feet) at West Antarctic Ice Sheet Divide (WAIS). The project will be completed over the next two years with some additional coring and borehole logging to obtain additional information and samples of the ice for the study of the climate record contained in the core.

As part of the project, begun six years ago, the team, funded by the National Science Foundation (NSF), has been drilling deep into the ice at the WAIS Divide site and recovering and analyzing ice cores for clues about how changes in the concentration of greenhouse gases in the atmosphere have influenced the Earth’s climate over time. (more…)