Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study finds human activity affects vertical structure of atmospheric temperature

18.09.2013
Human influences have directly impacted the latitude/altitude pattern of atmospheric temperature. That is the conclusion of a new report by scientists from Lawrence Livermore National Laboratory and six other scientific institutions. The research compares multiple satellite records of atmospheric temperature change with results from a large, multi-model archive of simulations.

"Human activity has very different effects on the temperature of the upper and lower atmosphere, and a very different fingerprint from purely natural influences," said Benjamin Santer, the lead researcher in the paper appearing in the Sept.16 online edition of the Proceedings of the U.S. National Academy of Sciences. "Our results provide clear evidence for a discernible human influence on the thermal structure of the atmosphere."


A graphic representation of the fingerprints, both manmade and natural, on the vertical structure of the atmosphere. Manmade changes such as the increased production of greenhouse gases causes the stratosphere to cool while the mid- to upper troposphere heats up. A new study shows that natural influences alone would not cause these temperature changes.

Observational satellite data and the computer model-predicted response to human influence have a common latitude/altitude pattern of atmospheric temperature change. The key features of this pattern are global-scale tropospheric warming and stratospheric cooling over the 34-year satellite temperature record. (The troposphere is the lowest portion of Earth's atmosphere. The stratosphere lies above the troposphere.)

"Current climate models are highly unlikely to produce this distinctive signal pattern by internal variability alone, or in response to naturally forced changes in solar output and volcanic aerosol loadings," Santer said.

Natural internal fluctuations in climate are generated by complex interactions of the coupled atmosphere-ocean system, such as the well-known El Nino/Southern Oscillation. External influences include human-caused changes in well-mixed greenhouse gases, stratospheric ozone and other radiative forcing agents, as well as purely natural fluctuations in solar irradiance and volcanic aerosols. Each of these external influences has a unique "fingerprint" in the detailed latitude/altitude pattern of atmospheric temperature change.

Fingerprint information has proved particularly useful in separating human, solar and volcanic influences on climate.

"The pattern of temperature change that has been observed vertically in the atmosphere, from ground level to the stratosphere, fits with what is expected from human-caused increases in greenhouse gases. The observed pattern conflicts with what would be expected from an alternative explanation, such as fluctuations in the sun's output," Santer said.

Another LLNL co-author of the paper, Celine Bonfils, noted that major volcanic eruptions also can profoundly disturb the vertical structure of atmospheric temperature. "During the recovery from such eruptions, tropospheric warming and stratospheric cooling also occur" Bonfils said. "But in contrast to volcanic influences, human-caused atmospheric temperature changes affect all latitudes and last longer. This suggests that the recent changes in temperature are not simply a recovery from past volcanic events."

Other Livermore scientists include Jeff Painter, Peter Gleckler, Charles Doutriaux and Karl Taylor. The research team included scientists from Remote Sensing Systems (Carl Mears and Frank Wentz), the Massachusetts Institute of Technology (Susan Solomon), the University of Adelaide, Australia (Tom Wigley), the NASA/Goddard Institute of Space Studies (Gavin Schmidt), the Canadian Centre for Climate Modelling and Analysis (Nathan Gillett) and the Nansen Environmental and Remote Sensing Center, Norway (Peter Thorne).

Founded in 1952, Lawrence Livermore National Laboratory provides solutions to our nation's most important national security challenges through innovative science, engineering and technology. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy's National Nuclear Security Administration.

Anne M Stark | EurekAlert!
Further information:
http://www.llnl.gov

More articles from Studies and Analyses:

nachricht The Great Unknown: Risk-Taking Behavior in Adolescents
19.01.2017 | Max-Planck-Institut für Bildungsforschung

nachricht A sudden drop in outdoor temperature increases the risk of respiratory infections
11.01.2017 | University of Gothenburg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland

19.01.2017 | Earth Sciences

Not of Divided Mind

19.01.2017 | Life Sciences

Molecule flash mob

19.01.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>