Navigation Links
Carbon dioxide controls Earth's temperature
Date:10/14/2010

NEW YORK -- Water vapor and clouds are the major contributors to Earth's greenhouse effect, but a new atmosphere-ocean climate modeling study shows that the planet's temperature ultimately depends on the atmospheric level of carbon dioxide.

The study, conducted by Andrew Lacis and colleagues at NASA's Goddard Institute for Space Studies (GISS) in New York, examined the nature of Earth's greenhouse effect and clarified the role that greenhouse gases and clouds play in absorbing outgoing infrared radiation. Notably, the team identified non-condensing greenhouse gases -- such as carbon dioxide, methane, nitrous oxide, ozone, and chlorofluorocarbons -- as providing the core support for the terrestrial greenhouse effect.

Without non-condensing greenhouse gases, water vapor and clouds would be unable to provide the feedback mechanisms that amplify the greenhouse effect. The study's results will be published Friday, Oct. 15 in Science.

A companion study led by GISS co-author Gavin Schmidt that has been accepted for publication in the Journal of Geophysical Research shows that carbon dioxide accounts for about 20 percent of the greenhouse effect, water vapor and clouds together account for 75 percent, and minor gases and aerosols make up the remaining five percent. However, it is the 25 percent non-condensing greenhouse gas component, which includes carbon dioxide, that is the key factor in sustaining Earth's greenhouse effect. By this accounting, carbon dioxide is responsible for 80 percent of the radiative forcing that sustains the Earth's greenhouse effect.

The climate forcing experiment described in Science was simple in design and concept -- all of the non-condensing greenhouse gases and aerosols were zeroed out, and the global climate model was run forward in time to see what would happen to the greenhouse effect.

Without the sustaining support by the non-condensing greenhouse gases, Earth's greenhouse effect collapsed as water vapor quickly precipitated from the atmosphere, plunging the model Earth into an icebound state -- a clear demonstration that water vapor, although contributing 50 percent of the total greenhouse warming, acts as a feedback process, and as such, cannot by itself uphold the Earth's greenhouse effect.

"Our climate modeling simulation should be viewed as an experiment in atmospheric physics, illustrating a cause and effect problem which allowed us to gain a better understanding of the working mechanics of Earth's greenhouse effect, and enabled us to demonstrate the direct relationship that exists between rising atmospheric carbon dioxide and rising global temperature," Lacis said.

The study ties in to the geologic record in which carbon dioxide levels have oscillated between approximately 180 parts per million during ice ages, and about 280 parts per million during warmer interglacial periods. To provide perspective to the nearly 1 C (1.8 F) increase in global temperature over the past century, it is estimated that the global mean temperature difference between the extremes of the ice age and interglacial periods is only about 5 C (9 F).

"When carbon dioxide increases, more water vapor returns to the atmosphere. This is what helped to melt the glaciers that once covered New York City," said co-author David Rind, of NASA's Goddard Institute for Space Studies. "Today we are in uncharted territory as carbon dioxide approaches 390 parts per million in what has been referred to as the 'superinterglacial.'"

"The bottom line is that atmospheric carbon dioxide acts as a thermostat in regulating the temperature of Earth," Lacis said. "The Intergovernmental Panel on Climate Change has fully documented the fact that industrial activity is responsible for the rapidly increasing levels of atmospheric carbon dioxide and other greenhouse gases. It is not surprising then that global warming can be linked directly to the observed increase in atmospheric carbon dioxide and to human industrial activity in general."


'/>"/>

Contact: Kathryn Hansen
kathryn.h.hansen@nasa.gov
301-614-5883
NASA/Goddard Space Flight Center
Source:Eurekalert

Related biology news :

1. Carbon nanostructures form the future of electronics and optoelectronics
2. Growth in the global carbon budget
3. Carbon sinks: Issues, markets, policy
4. Carbon dioxide scrubber captures greenhouse gases
5. UNC study on properties of carbon nanotubes, water could have wide-ranging implications
6. Study: Tropical wetlands hold more carbon than temperate marshes
7. Diatom genome helps explain success in trapping excess carbon in oceans
8. Earthworm activity can alter forests carbon-carrying capabilities
9. Global warming predicted to hasten carbon release from peat bogs
10. Revised theory suggests carbon dioxide levels already in danger zone
11. Engineer to present leak-proof method for carbon dioxide storage at international conference
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/13/2017)... According to a new market research report "Consumer IAM Market by ... Service, Authentication Type, Deployment Mode, Vertical, and Region - Global Forecast to ... USD 14.30 Billion in 2017 to USD 31.75 Billion by 2022, at ... ... MarketsandMarkets Logo ...
(Date:4/6/2017)... -- Forecasts by Product Type (EAC), Biometrics, ... (Transportation & Logistics, Government & Public Sector, Utilities / ... Facility, Nuclear Power), Industrial, Retail, Business Organisation (BFSI), Hospitality ... looking for a definitive report on the $27.9bn Access ... ...
(Date:4/3/2017)... April 3, 2017  Data captured by ... platform, detected a statistically significant association between ... to treatment and objective response of cancer ... to predict whether cancer patients will respond ... as well as to improve both pre-infusion potency ...
Breaking Biology News(10 mins):
(Date:6/27/2017)... ... 2017 , ... DuPont Pioneer (DuPont) and ERS Genomics (ERS) ... patent portfolio covering CRISPR-Cas genome editing technology for all agricultural uses and applications ... the CRISPR-Cas technology from co-inventor and co-owner Emmanuelle Charpentier, Ph.D. , “We ...
(Date:6/26/2017)... RESTON, Va (PRWEB) , ... June 26, 2017 , ... ... on the use of health IT to create efficiencies in healthcare information exchange and ... announced Donald W. Rucker, MD, head of the federal Office of the National Coordinator ...
(Date:6/23/2017)... ... June 23, 2017 , ... ... announced the latest version of LimitLIS®, its rapidly growing Laboratory Information System. , ... user adoption, ensure installation integrity, and provide more customization options. Each of these ...
(Date:6/23/2017)... ... June 23, 2017 , ... The ... hobbyists, and the University Aviation Association (UAA), the unifying voice for collegiate aviation ... Challenge will encourage teamwork, competition, and success through a STEM-based education platform. , ...
Breaking Biology Technology: