Tag Archives: atmosphere

NASA Research Confirms it’s a Small World, After All

By Guest PostAugust 17, 2011Scienceatmosphere, baseline interferometry, champs sur marne, changes in earth size, charles darwin, delft university of technology, doppler orbitography and radiopositioning integrated by satellite, earth expansion contraction theory, earth is a small world, earth lithosphere, earth orbit, earth radius, france, french satellite system, geophysical research letters, global climate change, global positioning system, grace, gravity recovery and climate experiment, ground navigation, high precision space geodesy, international terrestrial reference frame, land, large scale climate events like el nino and la nina, models of ocean bottom pressure, mother nature, NASA, ocean, solid earth, the netherlands, tracking spacecraft, walt disney, xiaoping wu

A NASA-led research team has confirmed what Walt Disney told us all along: Earth really is a small world, after all.

Since Charles Darwin’s time, scientists have speculated that the solid Earth might be expanding or contracting. That was the prevailing belief, until scientists developed the theory of plate tectonics, which explained the large-scale motions of Earth’s lithosphere, or outermost shell. Even with the acceptance of plate tectonics half a century ago, some Earth and space scientists have continued to speculate on Earth’s possible expansion or contraction on various scientific grounds.

Now a new NASA study, published recently in Geophysical Research Letters, has essentially laid those speculations to rest. Using a cadre of space measurement tools and a new data calculation technique, the team detected no statistically significant expansion of the solid Earth. (more…)

Ethane Levels Yield Information About Changes in Greenhouse Gas Emissions

By Guest PostAugust 14, 2011EnvironmentAntarctica, atmosphere, atmospheric methane, carbon dioxide, change in energy use, change in human activities, decline in methane emission, donald blake, eric saltzman, ethane, fossil fuel emissions, global temperatures, greenhouse gas, greenland, hydrocarbons, julie palais, kristal verhulst, methane, michael prather, murat aydin, polar ice sheets in greenland and antarctica, potent greenhouse gas, qi tang, twentieth century, university of california

*Research at Greenland and Antarctic shows decline in methane and ethane levels*

Recent data from NSF-funded research in both Greenland and Antarctica demonstrate that fossil-fuel related emissions of both methane and ethane, two of the most abundant hydrocarbons in the atmosphere, declined at the end of the twentieth century, according to a paper published Thursday in the journal Nature.

The causes of the decline in methane emission rates to the atmosphere have been puzzling scientists for some time. This new study shows that a change in human activities may have played a key role in the recent leveling off of methane, which, being a potent greenhouse gas contributes to global temperatures. (more…)

Study Assesses Nations’ Vulnerabilities to Reduced Mollusk Harvests from Ocean Acidification

By Guest PostAugust 7, 2011Environmentatmosphere, carbon dioxide emissions, carbonate shells or skeletons, changes in ocean chemistry, CO2, co2 levels, corrosive environment, fossil fuel, gambia, haiti, hauke kite powell, industrial revolution, Madagascar, marine ecosystems, marine environments, marine fisheries, mollusk aquaculture, mollusk harvests, mollusks, mozambique, noelle lucey, ocean acidification, ph, sarah cooley, scott doney, senegal, shellfish, transition decade, whoi, woods hole oceanographic institution, world oceans

Changes in ocean chemistry due to increased carbon dioxide (CO2) emissions are expected to damage shellfish populations around the world, but some nations will feel the impacts much sooner and more intensely than others, according to a study by scientists at Woods Hole Oceanographic Institution (WHOI).

As CO2 levels driven by fossil fuel use have increased in the atmosphere since the Industrial Revolution, so has the amount of CO2 absorbed by the world’s oceans, leading to changes in the chemical make-up of seawater. Known as ocean acidification, this decrease in pH creates a corrosive environment for some marine organisms such as corals, marine plankton, and shellfish that build carbonate shells or skeletons. (more…)

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…)