on November 16. The release of huge amounts of carbon from frozen methane hydrate from the ocean floor 56 million years ago, scientists associated with the largest change in the Earth’s climate since the asteroid that destroyed the dinosaurs, which, apparently, hit the Ground 9 million years earlier.
New research at rice University shows that such a scenario of historical events is quite possible.
No one knows for sure what started the process, but that the climate has changed and the temperature of the Earth has increased by an average of 8 degrees Celsius, no doubt. The planet was subjected to the effects of methane in the last 150 000 years, while the excess carbon in the oceans and the atmosphere, was not re-absorbed in sedimentary rocks.
The ecosystem of the Earth has changed, and many types of complex forms of living organisms disappeared during the Paleocene-Eocene thermal maximum (PETM) 56 million years ago, when the atmosphere and the oceans were 2 500 gigatons of carbon in the form of carbon dioxide.
In a new report, scientists from the Institute of rice, which was published in the journal Nature Geoscience, suggests that at that time, even though containing methane gas hydrates — \»ice that burns\» — took a small zone of the sediment beneath the seabed until PETM, its quantity can be compared to today.
This fact concerned scientists, who believe that the burning of fossil fuels today may at some point cause the reverse process. Enough to compromise the stability of deposits of gas hydrates in the permafrost zone below the sea floor, and this change can warm the atmosphere and initiate the release of methane, a more powerful gas against the dangers of the greenhouse effect than carbon dioxide. This will repeat the history that took place more than 50 million years ago.
In the ocean organisms die, sink to the bottom and decompose into methane. Under high pressure and under the influence of low temperatures the molecules of methane \»fall into a snare, into supramolecular compound methane with water, known as gas hydrate, which is stabilized in a dense thin layer under the bottom of the ocean.
To PATM oceans were warmer, which means that the layer of gas hydrate was supposed to be more dense than today. This version was originally held some scientists from Rasa, headed by Gerald Dickens, a Professor of natural Sciences. Opponents claimed that the higher temperature of the ocean waters may not necessarily be associated with a large number of methane hydrate, \» says George W. Hirasaki, Professor of chemical engineering. But, using the numerical model, we found that if the oceans were warmer, they would contain less dissolved oxygen, and conditions for the formation of methane would be more favorable\».
When scientists come to the same conclusion, they conducted a computer simulation, the result of which was that the zone of stability of methane hydrate (smaller by volume than the one that exists today) probably contained approximately the same amount of methane hydrate. It turns out that methane hydrate was more concentrated, which means that for an abrupt release of methane into the atmosphere and the ocean, which would lead to global climate change would require the collapse of only one-third of gas deposits.
The causality of the process that started the cycle of carbon discharge, remains a mystery. On the one hand, the decomposition of gas hydrates could be linked to a rapid warming of the climate, as these supramolecular formation is not stable at high temperatures. On the other hand, the warming could be caused by the decomposition of methane hydrate, as methane is a gas that can cause the strongest greenhouse effect. In any case, it is still unclear cause, which has launched or one, or another process.
To understand that launched PATM extremely important. \»There is a risk that the history of carbon lunge into the atmosphere and the ocean can be repeated, but faster, given the environmental situation is complicated by the life of our civilization\» — says Dickens. Scientist found it necessary to add that methane hydrate can be a valuable source of clean energy as burning methane produces significantly less carbon dioxide than any fossil fuels minerals.
Methane emissions occurred 56 million years ago, changed the climate and composition of the earth, from its origins up to the top of geospheres, not to mention the changes in nature — the extinction of species and changing types of mammals. It is important that we can see the reaction of the planet the climate anomaly — over 150 thousand years the Earth has returned to normal.
The study was supported and sponsored by the Ministry of energy of the United States of America.