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 World’s oldest known oxygen oasis discovered
18.01.2018 | Eberhard Karls Universität Tübingen

nachricht A close-up look at an uncommon underwater eruption
11.01.2018 | Woods Hole Oceanographic Institution

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>