New research suggests slow but significant greenhouse gas emissions from perpetual underwater frostbite.
In the far north, the Arctic Ocean is flooded with vast areas of coastal tundra and steppe ecosystems. Although the ocean water was only a few degrees above freezing, it began to melt the constant frost beneath it, destroying billions of tons of organic matter. Degradable organic matter began to produce CO2 և CH4, one of the two most important greenhouse gases.
Although researchers have been studying underwater frost for decades, the difficulty of collecting and exchanging data in international disciplinary departments has prevented an overall assessment of carbon emissions and emission rates. A new study led by Dr. Candidate Sarah Sayed և Senior Research Fellow Dr. Ben Abbott at Brigham Young University (BYU) Published in IOP Publishing Journal Environmental research letters, sheds light on the feedback of the submarine perpetual frost climate, leading to the first theory of peripheral carbon reserves, greenhouse gas emissions, and the possible further response of the submarine telescope zone.
Saidin միջազգային An international team of 25 researchers on perpetual frostbite worked with the Permafrost Carbon Network (PCN) system, supported by the US National Science Foundation. Researchers have combined the results of published unpublished studies to assess past and present underwater carbon reserves and how much greenhouse gas it can produce over the next three centuries.
Experts estimate that currently underwater evergreen ice traps 60 billion tonnes of methane, with 560 billion tonnes of organic carbon in the sediment և soil. As a reference, since the Industrial Revolution, people have emitted a total of about 500 billion tons of carbon into the atmosphere. This forces permanent underwater freezing carbon stocks with feedback from a potentially giant ecosystem of climate change.
“Eternal submarine frost is truly unique because it still responds to abrupt climate change more than ten thousand years ago,” said Sayedi. “In some ways, it can give us a glimpse of the constant frostbite that is melting today due to human activity.”
Sayedi’s team estimates that the perpetual underwater frost is already emitting significant amounts of greenhouse gases. However, this release is largely due to climate change rather than current human activity. They estimate that perpetual underwater frost emits about 140 million tons of CO2 և 5.3 million tons of CH4 each year. This is similar in size to the overall greenhouse gas emissions in Spain.
Researchers have found that if man-made climate change continues, CH4 և CO2 emissions from underwater permanent ice can increase significantly. However, this response is expected to occur over the next three centuries rather than abruptly. The researchers estimated that the amount of future greenhouse gas emissions from submarine freezing depends directly on future human emissions. They found that under the usual scenario, warming underwater freezing releases four times more CO2 և CH4 than when human emissions are reduced to less than 2 ° C.
“These results are significant because they indicate climate-significant but slow feedback,” Sayed explained. “Some coverage of this period suggests that human emissions could catastrophically release methane hydrates, but our study suggests that it is gradually increasing over many decades.”
Even though the feedback from this climate is relatively gradual, researchers note that perpetual underwater frost is not included in current climate agreements or greenhouse gas targets. Sayedi stressed that there is still a lot of uncertainty about the underwater telescope, that further research is needed.
“Compared to how important an underground field can be for the future climate, we know very little about this ecosystem,” said Sayedi. “We need more sediment-soil samples, like a better monitoring network, to find out when greenhouse gas emissions respond to current heating, how fast this huge carbon reservoir will wake up from its frozen slumber.”
Summary of main scientific points.
- Underwater permafrost has been melting since the end of the last glacial period (14,000,000 years ago) when it began to flood the ocean.
- An international team of 25 permanent frostbite researchers estimates that the underwater evergreen region currently traps 60 billion tonnes of methane and 560 billion tonnes of organic carbon in sediment. However, the exact amount of these carbon reserves remains highly uncertain.
- This carbon is already being released from the period of constant underwater frost, although it is still unclear whether this is a natural response to defrosting or whether anthropogenic heating accelerates greenhouse gas emissions and emissions.
- Researchers estimate that approximately 140 million tonnes of CO2 և 5.3 million tonnes of CH4 are currently released into the atmosphere each year. This represents a small fraction of the total anthropogenic greenhouse gas emissions, roughly equal to the Spanish greenhouse gas emissions.
- Experts predict a gradual increase in emissions from underwater permanent ice, rather than a sharp increase in emissions over the next three hundred years.
- The amount of greenhouse gas emissions depends on how much human emissions are reduced. Experts estimate that about 1% of additional underwater emissions can be avoided if people actively reduce their emissions compared to the no-mitigation scenario.
- This climate feedback is still virtually absent from climate policy discussions; more field observations are needed to better predict the future of this system.
Quotes from other co-authors.
“I think there are three important messages from this study. First of all, perpetual underwater frostbite is probably not a time bomb on hair extensions. Second, perpetual underwater frost is a potentially large-scale climate response that should be considered in climate negotiations. Third, there is still a huge amount of money we do not know about this system. “We really need more research, including international cooperation on research in the Nordic countries.”
– Dr. Ben Abbott, Senior Research Fellow, Brigham Young University
“This work demonstrates the power of the Science Synthesis Network by engaging experts in a variety of subjects to assess the state of our knowledge based on current observations and models. “While scientific work will continue to test these ideas, the combination of knowledge with this expert assessment provides a solid basis for further research into underwater evergreen greenhouse gas emissions.”
– Dr. Ted Shour, Chief Investigator, Permafrost Carbon Network, University of Northern Arizona
“This expert assessment is a crucial contribution to the scientific literature in developing our knowledge of the potential for greenhouse gas emissions from our hitherto unexplored reservoir. The integration of scientists from many disciplines, institutions, and countries has made it possible to move from individual data points or studies that provide a much more comprehensive assessment of the underwater telescope. »
– Dr. Christina Schodel, Co-Investigator, Permafrost Carbon Network, University of Northern Arizona
Reference. “Side Sarah Sayedi, Benjamin W. Abbott, Brett F. Thornton, enn jennifer M. Frederick, ori osen Fonk, Paul Overduin, Christina Schodel, Edward A. Shur, Annie Bourbon, “Carbon Resources of Persistent Marine Frost և Climate Change Sensitivity Assessed by Expert Assessment” Nikita Demidov, Anatoly Gavrilov, Shengping He, Gustaf Hugelius, Martin Jacobson, Miriam JJ, Miriam J Joo Robbie W. MacDonald, A. , Alexander Vasily և, Sebastian Westerman, ay ay P arn arnetske, Tingjun hang ang, Mehran nde andheri, Sarah Baumler, Brian S. Brown և Rebecca Fre Frey, December 22, Environmental research letters,
DOI: 10.1088 / 1748-9326 / abcc29:
This research was funded by the US National Science Foundation և BYU PhD.