Tag Archives: clouds

NASA Satellite Finds Earth’s Clouds are Getting Lower

Earth’s clouds got a little lower — about one percent on average — during the first decade of this century, finds a new NASA-funded university study based on NASA satellite data. The results have potential implications for future global climate.

Scientists at the University of Auckland in New Zealand analyzed the first 10 years of global cloud-top height measurements (from March 2000 to February 2010) from the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA’s Terra spacecraft. The study, published recently in the journal Geophysical Research Letters, revealed an overall trend of decreasing cloud height. Global average cloud height declined by around one percent over the decade, or by around 100 to 130 feet (30 to 40 meters). Most of the reduction was due to fewer clouds occurring at very high altitudes. (more…)

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NASA Satellite Tracks Menacing Australian Cyclone

Fresh on the heels of a series of crippling floods that began in December 2010, and a small tropical cyclone, Anthony, this past weekend, the northeastern Australian state of Queensland is now bracing for what could become one of the largest tropical cyclones the state has ever seen.

The Atmospheric Infrared Sounder (AIRS) instrument on NASA’s Aqua satellite, built and managed by NASA’s Jet Propulsion Laboratory, Pasadena, Calif., captured this infrared image of Yasi on Jan. 31, 2011, at 6:29 a.m. PST (9:29 a.m. EST). The AIRS data create an accurate 3-D map of atmospheric temperature, water vapor and clouds, data that are useful to forecasters. The image shows the temperature of Yasi’s cloud tops or the surface of Earth in cloud-free regions. The coldest cloud-top temperatures appear in purple, indicating towering cold clouds and heavy precipitation. The infrared signal of AIRS does not penetrate through clouds. Where there are no clouds, AIRS reads the infrared signal from the surface of the ocean waters, revealing warmer temperatures in orange and red. (more…)

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Broken Glass Yields Clues to Climate Change

*Ordinary drinking glasses and atmospheric dust particles break apart in similar patterns*

Clues to future climate may be found in the way an ordinary drinking glass shatters.

Results of a study published this week in the journal Proceedings of the National Academy of Sciences find that microscopic particles of dust can break apart in patterns that are similar to the fragment patterns of broken glass and other brittle objects. (more…)

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Study Portends Greater Anticipated Global Warming

Current state-of-the-art global climate models predict substantial warming in response to increases in greenhouse gases such as carbon dioxide. The models, though, disagree widely in the magnitude of the warming we can expect. The disagreement among models is mainly due to the different representation of clouds. Some models predict that global mean cloud cover will increase in a warmer climate and the increased reflection of solar radiation will limit the predicted global warming. Other models predict reduced cloudiness and magnified warming. (more…)

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Taking Measure of the Greenhouse Effect

WASHINGTON — Scientists have long known that heat-absorbing components of Earth’s atmosphere, such as clouds and certain gases, prevent our planet from being an ice-covered ball. Now a study, for the first time, comprehensively calculates the relative contributions of the components responsible for that heating, known as the greenhouse effect.

Besides clarifying an important aspect of climate science, the study also demonstrates that rising concentrations of one heat-trapping gas — carbon dioxide — leads to much more greenhouse warming than just the heat the gas absorbs directly itself.

Various studies have looked at the contributions of water vapor, CO2, and other greenhouse gases. But none had systematically estimated the contributions of each of the main players, says climate scientist Gavin Schmidt of NASA Goddard Institute for Space Studies, and lead author of the new research. (more…)

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