Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rapid Release of Sea-Floor Methane Caused Extreme Global Warming 55 Million Years Ago

13.05.2003


Scientists have just returned from two months at sea aboard the oceanographic drill ship JOIDES Resolution where they studied the effects of a larger than expected methane release 55 million years ago that may have caused extreme global warming.



In March, the scientists traveled to a site near Walvis Ridge — an ancient submarine mountain chain off Africa—as part of the NSF-supported Ocean Drilling Program (ODP) Leg 208. The researchers searched for evidence of roughly 2,000 gigatons of methane they believe escaped into the ocean and atmosphere to cause the Paleocene-Eocene Thermal Maximum, an extreme global warming event that is unique in Earth history in both magnitude and rate of warming.

Sediments far below the seafloor hold clues to the cause of this warming. Evidence for the dissolution of methane was recorded in debris that settled, layer by layer, on the ocean floor over thousands of years.


Cores of sediment brought up from the study site suggested a significant amount of methane dissolution, said ODP scientist Jim Zachos of the University of California at Santa Cruz, perhaps twice the original estimate.

"It far exceeds what has been estimated by models, assuming a release of 2,000 gigatons of methane," added Dick Kroon of Vrije Universiteit Amsterdam, a fellow researcher aboard JOIDES Resolution.

The initial results also suggest that Earth’s recovery to a "normal state" took as long as 100,000 years.

Geochemists speculate that the methane escaped from sea-floor clathrates, methane-trapping ice-crystals that are distributed in sediments on the outer edges of continental margins worldwide. For reasons that remain unknown, the clathrates suddenly began to decompose on a massive scale at the time of the Paleocene-Eocene Thermal Maximum, increasing the amount of methane in the atmosphere and oceans.

The rapid release of so much methane, and the methane’s oxidation to carbon dioxide, would have significantly altered ocean chemistry, and ultimately the atmosphere and global climate. The process appears to have lasted for a period of 40,000 years, scientists say, warming Earth by more than five degrees Celsius.

"We suspect the melting of clathrates and subsequent rapid release of methane was initiated by a gradual warming that pushed the climate system across a threshold," said Zachos. Once started, the release of methane and the resultant warming likely fueled the release of more methane, a phenomenon of concern for future global climate change, he added.

ODP is an international partnership of scientists and research institutions organized to study the evolution and structure of the Earth. It is funded by NSF with substantial contributions from international partners.

NSF Science Expert: Bruce Malfait, bmalfait@nsf.gov

Cheryl Dybas | NSF
Further information:
http://www.nsf.gov/od/lpa/news/03/tip030512.htm

More articles from Earth Sciences:

nachricht How much biomass grows in the savannah?
16.02.2017 | Friedrich-Schiller-Universität Jena

nachricht Canadian glaciers now major contributor to sea level change, UCI study shows
15.02.2017 | University of California - Irvine

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Switched-on DNA

20.02.2017 | Materials Sciences

Second cause of hidden hearing loss identified

20.02.2017 | Health and Medicine

Prospect for more effective treatment of nerve pain

20.02.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>