Tag Archives: atmosphere

Deforestation Causes Cooling in northern U.S., Canada

Deforestation, considered by scientists to contribute significantly to global warming, has been shown by a Yale-led team to actually cool the local climate in northern latitudes, according to a paper published Nov. 17 in Nature.

“If you cut trees in the boreal region, north of 45 degrees latitude, you have a net cooling effect,” says Xuhui Lee, the study’s principal investigator and professor of meteorology at the Yale School of Forestry & Environmental Studies. “You release carbon into the atmosphere by cutting down trees, but you increase the albedo effect — the reflection of sunlight.” (more…)

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NASA Probe Data Show Liquid Water Evidence on Europa

PASADENA, Calif. — Data from a NASA planetary mission have provided scientists evidence of what appears to be a body of liquid water, equal in volume to the North American Great Lakes, beneath the icy surface of Jupiter’s moon, Europa.

The data suggest there is significant exchange between Europa’s icy shell and the ocean beneath. This information could bolster arguments that Europa’s global subsurface ocean represents a potential habitat for life elsewhere in our solar system. The findings are published in the scientific journal Nature. (more…)

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Prehistoric Greenhouse Data from Ocean Floor Could Predict Earth’s Future, MU Study Finds

*Evidence of water mass moving south 70 million years ago shows how warmth was distributed*

COLUMBIA, Mo. – New research from the University of Missouri indicates that Atlantic Ocean temperatures during the greenhouse climate of the Late Cretaceous Epoch were influenced by circulation in the deep ocean. These changes in circulation patterns 70 million years ago could help scientists understand the consequences of modern increases in greenhouse gases.

“We are examining ocean conditions from several past greenhouse climate intervals so that we can understand better the interactions among the atmosphere, the oceans, the biosphere, and climate,” said Kenneth MacLeod, professor of geological sciences in the College of Arts and Science. “The Late Cretaceous Epoch is a textbook example of a greenhouse climate on earth, and we have evidence that a northern water mass expanded southwards while the climate was cooling. At the same time, a warm, salty water mass that had been present throughout the greenhouse interval disappeared from the tropical Atlantic.” (more…)

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U.S. Rivers and Streams Saturated With Carbon

*Significant amount of carbon in land is leaking into streams and rivers, then to the atmosphere*

Rivers and streams in the United States are releasing substantially more carbon dioxide into the atmosphere than previously thought.

This according to researchers publishing their results in the current issue of the journal Nature Geoscience. (more…)

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Extreme Space Weather at Mercury Blasts the Planet’s Poles

ANN ARBOR, Mich.— The solar wind sandblasts the surface of planet Mercury at its poles, according to new data from a University of Michigan instrument on board NASA’s MESSENGER spacecraft.

The sodium and oxygen particles the blistering solar wind kicks up are the primary components of Mercury’s wispy atmosphere, or “exosphere,” the new findings assert. Through interacting with the solar wind, they become charged in a mechanism that’s similar to the one that generates the Aurora Borealis on Earth. (more…)

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Water Evaporated from Trees Cools Global Climate

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…)

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

*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 21st century as the soil warms in response to climate change. (more…)

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

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…)

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