Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

What Is Guilty Of Warming: Methane Or Carbonic Acid Gas?

10.07.2007
Back in the early 1990s, researchers found that the earth's surface temperature increased rather quickly by 5 to 9 degrees about 55 million years ago, and this warming lasted for about 100,000 years.

Some climatologists explain this warming by methane discharges into the atmosphere. This methane hypothesis was reviewed by the specialists of the Obukhov Insititue of Atmospheric Physics, Russian Academy of Sciences, under the guidance of Academician Georgy Golitsyn. According to the researchers’ opinion, quick (in terms of geology) methane-based warming is possible in principle, although it requires considerable methane streams from the interior of the Earth.

Within the long history of the Earth, its climate has changed a lot of times. The orbit parameters changed, continents and oceans shifted on the planet, big asteroids fell down on the Earth and volcanoes began to erupt. In the last decade of the 20th century, scientific community started to discuss one more possibility for climatic changes, which are long-term in terms of human history and quick in terms of geological time scale. This is the so-called “methane catastrophe” – discharge of large quantity of methane from gas hydrates located in the interior of the Earth. As a result, the climate got warmer within 15-30,000 years, which noticeably changed the late Palaeocene world. However, many researchers assume that the reason for global warming was quick increase of carbonic acid gas concentration in the atmosphere. So, what is to blame: carbonic acid gas or methane?

In 1750 during the pre-industrial epoch, the terrestrial atmosphere contained approximately 1,85 Gt of methane. To explain the warming that occurred 55 million years ago, the methane concentration would have increased by over a hundred times as compared to pre-industrial levels, and the carbonic acid gas concentration by only six times. As there was a sufficient quantity of methane in the interior of the Earth, estimated at between 700 and 30,000 Gt, it is possible that between 1,000 and 2,000 Gt was discharged from the interior of the Earth, of which 400 Gt fell on the Arctic permafrost zone.

Due to the molecular mass difference, carbonic dioxide formation requires 2,75 times more carbon than formation of the same quantity of methane, and as methane is a stronger greenhouse gas than carbonic dioxide, its potential would be 21 times higher than a similar potential of carbonic acid gas. If different absorbent properties of greenhouse gases are taken into account, then greenhouse warming due to methane concentration would have required six times less carbon than the warming due to carbonic acid gas, and, accordingly, much smaller discharge of carbon from the planet interior would have been sufficient.

There are other arguments in favor of the “methane” hypothesis. As the methane concentration in the atmosphere increases, its stability also grows. Thus, in the pre-industrial epoch, the methane molecule lifespan in the atmosphere was 8,4 years, in contemporary conditions - about 10 years, but 55 million years ago, during massive gas discharges, it could exceed 40 years. Besides, in case of high concentration of greenhouse gases in the atmosphere, the water vapour concentration also grows, which increases the greenhouse effect. To achieve the same increase of surface temperature (taking into account the water vapour influence), twice lower methane content in the atmosphere (and less discharge from gas hydrates) would have been sufficient. According to the Russian researchers’ estimates, during the warming period, the annual methane stream into the atmosphere should have been 25 Gt, if the methane molecule lived for 10 years, and 6 Gt, if its lifespan was increased up to 40 years. (In the contemporary world, the major methane leakage from the interior of the Earth occurs owing to natural gas production and makes about 600 Mt per year, and the atmosphere contains 4,6 Gt of methane).

The above estimates demonstrate that quick (in terms of geology) methane-based warming is possible in principle, although it requires considerable methane discharges. Probably, volley methane discharges in the geological past could be the trigger to launch the “quick” warming process. According to the recent palaeontological data, the methane concentration growth normally passes ahead of the temperature growth. Such mechanism explains why some warmings in the history of the Earth had happened earlier than the carbonic acid gas concentration increased.

Nevertheless, the Russian researchers point out that detailed review of the greenhouse phenomenon at the Palaeocene/Eocene border has not been finished yet. It requires further investigation with involvement of geological, geochemical and paleoenvironmental records and contemporary climatic theory models.

Nadezda Markina | alfa
Further information:
http://www.informnauka.ru

More articles from Earth Sciences:

nachricht Predicting unpredictability: Information theory offers new way to read ice cores
07.12.2016 | Santa Fe Institute

nachricht Sea ice hit record lows in November
07.12.2016 | University of Colorado at Boulder

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>