Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cosmic Rays Are Not the Cause of Climate Change, Scientists Say

22.01.2004

Eleven Earth and space scientists say that a recent paper attributing most climate change on Earth to cosmic rays is incorrect and based on questionable methodology. Writing in the January 27 issue of Eos, published by the American Geophysical Union, Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research and colleagues in Canada, France, Germany, Switzerland, and the United States challenge the cosmic ray hypothesis.

In July 2003, astrophysicist Nir Shaviv and geologist Jan Veizer wrote in GSA Today that they had established a correlation between cosmic rays and temperature evolution over hundreds of millions of years. They also claimed that current global warming is not primarily caused by human emissions of carbon dioxide. Their findings have been widely reported in international news media.

According to Rahmstorf, Shaviv and Veizer’s analyses--and especially their conclusions--are scientifically ill-founded. The data on cosmic rays and temperature so far in the past are extremely uncertain, he says. Further, their reconstruction of ancient cosmic rays is based on only 50 meteorites, and most other experts interpret their significance in a very different way, he says. He adds that two curves presented in the article show an apparent statistical correlation only because the authors adjusted the data, in one case by 40 million years. In short, say the authors of the Eos article, Shaviv and Veizer have not shown that there is any correlation between cosmic rays and climate.

As for the influence of carbon dioxide in climate change, many climatologists were surprised by Shaviv and Veizer’s claim that their results disproved that current global warming was caused by human emissions, Rahmstorf says. Even if their analysis were methodologically correct, their work applied to time scales of several million years.

The current climate warming has, however, occurred during just a hundred years, for which completely different mechanisms are relevant, he says. For example, over millions of years, the shifting of continents influences climate, while over hundreds of thousands of years, small changes in Earth’s orbit can initiate or terminate ice ages. But for time periods of years, decades, or centuries, these processes are irrelevant. Volcanic eruptions, changes in solar activity, and the concentration of greenhouse gases, as well as internal oscillations of the climate system, are crucial on this scale.

The 11 authors of the Eos article affirm that the strong increase of carbon dioxide and some other greenhouse gases in the atmosphere due to manmade emissions is most probably the main cause of the global warming of the last few decades. The most important physical processes are well understood, they say, and model calculations as well as data analyses both come to the conclusion that the human contribution to the global warming of the 20th century was dominant.

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

More articles from Earth Sciences:

nachricht Sea ice extent sinks to record lows at both poles
23.03.2017 | NASA/Goddard Space Flight Center

nachricht Less radiation in inner Van Allen belt than previously believed
21.03.2017 | DOE/Los Alamos National Laboratory

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

When Air is in Short Supply - Shedding light on plant stress reactions when oxygen runs short

23.03.2017 | Life Sciences

Researchers use light to remotely control curvature of plastics

23.03.2017 | Power and Electrical Engineering

Sea ice extent sinks to record lows at both poles

23.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>