Tag Archives: atmosphere

Water Evaporated from Trees Cools Global Climate

By Guest PostSeptember 17, 2011Environmentatmosphere, central park, earth, emissions of carbon dioxide, evaporated water, evaporation, george ban-weiss, global balance of energy, global climate, global warming, govindasamy bala, greenhouse gas, julia pongratz, ken caldeira, new york, vegetation, water, water vapor

Washington, DC — Scientists have long debated about the impact on global climate of water evaporated from vegetation. New research from Carnegie’s Global Ecology department concludes that evaporated water helps cool the earth as a whole, not just the local area of evaporation, demonstrating that evaporation of water from trees and lakes could have a cooling effect on the entire atmosphere. These findings, published September 14 in Environmental Research Letters, have major implications for land-use decision making.

Evaporative cooling is the process by which a local area is cooled by the energy used in the evaporation process, energy that would have otherwise heated the area’s surface. It is well known that the paving over of urban areas and the clearing of forests can contribute to local warming by decreasing local evaporative cooling, but it was not understood whether this decreased evaporation would also contribute to global warming (more…)

Thawing Permafrost Could Release Vast Amounts of Carbon and Accelerate Climate Change by the end of this Century

By Guest PostAugust 27, 2011Environmentalternative energies and atomic energy commission, amount of soil carbon, atmosphere, berkeley lab, boreal and arctic land ecosystems, canada, carbon, carbon dioxide, charles koven, climate changes, combine, computer modeling, energy, European Union, france, frozen soils, global warming, high latitude permafrost, intergovernmental panel on climate change, land surface ecosystem model, lawrence berkeley national laboratory, methane emissions, orchidee, organic matter, plant growth, project, rate of soil carbon decomposition, simulation, supercomputing facility, temperature, united kingdom

*New computer modeling study, led by a Berkeley Lab scientist, could help revise understanding of permafrost’s role in global warming*

Billions of tons of carbon trapped in high-latitude permafrost may be released into the atmosphere by the end of this century as the Earth’s climate changes, further accelerating global warming, a new computer modeling study indicates.

The study also found that soil in high-latitude regions could shift from being a sink to a source of carbon dioxide by the end of the 21^st century as the soil warms in response to climate change. (more…)

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…)

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…)