Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Climate Model Predicts Greater 21st Century Warming

20.05.2003

For the first time, scientists have incorporated multiple human and natural factors into a climate projection model. They predict that increased carbon dioxide in the atmosphere, due to changes in the carbon cycle, combined with a decrease in human-produced sulphates, may cause accelerated global warming during the 21st century, as compared with simulations without these feedback effects.

Results of the study, completed by Chris D. Jones and colleagues at the Met Office’s Hadley Centre for Climate Prediction and Research in Bracknell, United Kingdom, appear in the journal Geophysical Research Letters, published by the American Geophysical Union.

Previous studies have indicated that human activities, such as carbon dioxide and sulphate emissions, as well as natural factors, such as changes in solar radiation, emissions from volcanic eruptions and interactions between climate and the carbon cycle, are important mechanisms for causing climate change. No previous climate studies have, however, integrated all of these factors into a single climate experiment.

The climate-carbon cycle experiment completed by Jones and his colleagues is the first to take a more comprehensive Earth-systems approach to climate modeling. This "all-forcings experiment," or ALL, incorporates carbon dioxide emissions, non-carbon dioxide greenhouse gases, human-produced sulphate aerosol levels, the reflection of solar radiation associated with sulphate in the atmosphere (the "albedo effect"), atmospheric ozone levels, levels of solar radiation, the effects of volcanic eruptions, and climate-carbon cycle feedbacks.

Discrepancies between observed temperature trends in the 20th century and climate simulations that consider only a limited number of factors have hindered the ability of some models to predict future climate change. The ALL model was, however, able to recreate observed temperature records for the 20th century, illustrating the importance of including multiple factors in climate change projections. Also, the rise in carbon dioxide simulated by ALL more closely matches the observed carbon dioxide rise than did previous models. The researchers say that this indicates that mechanisms other than direct carbon dioxide emissions caused by human activity also contribute to the observed trend. Jones and his colleagues were also able to replicate estimates of the amount of carbon currently stored in the oceans and on land worldwide.

With regard to future climate predictions, ALL shows that predicted reductions in human sulphate emissions will cause a reduction in the cooling effect associated with sulphates in the atmosphere, or a net warming. The model predicts that the resultant warming will enhance soil respiration, meaning that the increased amounts of carbon stored in the soil during the 20th century will be released into the atmosphere, causing a faster rise in atmospheric carbon dioxide. By the end of the 21st century, the authors state, the increase in carbon dioxide and decrease of sulphates will cause a substantially higher global warming of 5.5 degrees Celsius [9.9 degrees Fahrenheit] compared with 4 degrees Celsius [7 degrees Fahrenheit] when these interactions are neglected.

The research was supported by the UK Department for the Environment, Food and Regional Affairs.

Harvey Leifert | AGU
Further information:
http://www.agu.org

More articles from Earth Sciences:

nachricht Geophysicists and atmospheric scientists partner to track typhoons' seismic footprints
16.02.2018 | Princeton University

nachricht NASA finds strongest storms in weakening Tropical Cyclone Sanba
15.02.2018 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

'Lipid asymmetry' plays key role in activating immune cells

20.02.2018 | Life Sciences

MRI technique differentiates benign breast lesions from malignancies

20.02.2018 | Medical Engineering

Major discovery in controlling quantum states of single atoms

20.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>