Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Atmospheric water clusters provide evidence of global warming

25.02.2004


Hamilton College professor/students publish findings in JACS



Researchers at Hamilton College have identified several methods for successfully determining the structures and thermodynamic values for the formation of atmospheric water clusters, which scientists have speculated may accelerate global warming. The Hamilton team’s findings were published in the March 3 issue of the Journal of the American Chemical Society.

The greenhouse effect is caused by molecules that absorb infrared radiation released from the Earth’s surface, trapping heat in the atmosphere. Water acts as a greenhouse gas because it is one of the molecules that can absorb infrared radiation and cause warming. "Our research supports the suggestion that in a global warming scenario higher temperatures will lead to increased absorption of solar radiation by water clusters," said lead author, George Shields, the Winslow Professor of Chemistry at Hamilton College. "The prediction that higher order water clusters (trimers, tetramers, and pentamers) are present in the atmosphere is significant because it shows that these entities must be considered as key players in atmospheric processes."


Previous research has hypothesized that water clusters (two or more water molecules held together by hydrogen bonds) could catalyze acid rain or the formation of aerosol in the atmosphere, and even lead to acceleration of the Greenhouse effect. All of these ideas depend on the presence of water clusters in the troposphere, the region of the atmosphere that is directly heated by the Earth’s surface. The Hamilton group can now predict the concentration of water clusters present in the troposphere. Large water clusters have for some time been thought to catalyze reactions which have implications for the chemistry that takes place in the atmosphere. A paper in the June 27, 2003 issue of Science documented the first detection of a water dimer (two hydrogen bonded water molecules) in the troposphere.

Shields said, "Once we knew the dimers were present, we investigated whether larger water clusters might also be involved in a variety of atmospheric chemistry processes. We started by using high level quantum chemistry methods to predict dimer concentrations that would be found on a warm, humid day. The accuracy of our dimer calculation, which matched the experimentalists’ detection of water dimer concentrations under the same conditions, led us to calculate the concentration of other water clusters in the troposphere." The researchers found that water clusters consisting of cyclic trimers, cyclic tetramers, and cyclic pentamers should all be detectable in the lower troposphere.

The Hamilton researchers used the documented information on water cluster structures to investigate the effectiveness of various model chemistries in modeling gas-phase water cluster formation. The performance of these chemistries was compared against previous calculations, and the Hamilton team found that thermodynamic calculations by Gaussian-2, Gaussian-3 and Complete Basis Set-APNO chemistries compared quite well to the prior calculations. (Experimentalists reported a value of 6 x 10^14 dimers per cubic centimeter at 292 K on a 100% humid day. The Hamilton study predicted a value of 4 x 10^14 dimers per cubic centimeter at 292 K.)


George Shields conducted the research with two undergraduate students, Meghan Dunn and Emma Pokon. The research was made possible through funding from the American Chemical Society/Petroleum Research Fund, Merck/AAAS, the Camille and Henry Dreyfus Foundation, and from NSF Grant CHE-0116435 for supercomputer instrumentation as part of the MERCURY supercomputer consortium (http://mars.hamilton.edu).

Sharon Rippey | EurekAlert!
Further information:
http://mars.hamilton.edu
http://www.hamilton.edu/

More articles from Earth Sciences:

nachricht NASA eyes Pineapple Express soaking California
24.02.2017 | NASA/Goddard Space Flight Center

nachricht 'Quartz' crystals at the Earth's core power its magnetic field
23.02.2017 | Tokyo Institute of Technology

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>