Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change
Paleooceanographic evidence has been used to postulate that methane from oceanic hydrates may have had a significant role in regulating global climate, implicating global oceanic deposits of methane gas hydrate as the main culprit in instances of rapid climate change that have occurred in the past....
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ftosti:oai:osti.gov:935357 2023-07-30T04:01:35+02:00 Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change Reagan, Matthew Reagan, Matthew T. Moridis, George J. 2008-08-25 application/pdf http://www.osti.gov/servlets/purl/935357 https://www.osti.gov/biblio/935357 unknown http://www.osti.gov/servlets/purl/935357 https://www.osti.gov/biblio/935357 54 ARCTIC REGIONS CARBON CLIMATE MODELS CLIMATES DISSOCIATION DISTRIBUTION GAS HYDRATES HYDRATES INSTABILITY METHANE NATURAL GAS HYDRATE DEPOSITS OXIDATION SATURATION SEDIMENTS SIMULATION SOURCE TERMS 2008 ftosti 2023-07-11T08:46:15Z Paleooceanographic evidence has been used to postulate that methane from oceanic hydrates may have had a significant role in regulating global climate, implicating global oceanic deposits of methane gas hydrate as the main culprit in instances of rapid climate change that have occurred in the past. However, the behavior of contemporary oceanic methane hydrate deposits subjected to rapid temperature changes, like those predicted under future climate change scenarios, is poorly understood. To determine the fate of the carbon stored in these hydrates, we performed simulations of oceanic gas hydrate accumulations subjected to temperature changes at the seafloor and assessed the potential for methane release into the ocean. Our modeling analysis considered the properties of benthic sediments, the saturation and distribution of the hydrates, the ocean depth, the initial seafloor temperature, and for the first time, estimated the effect of benthic biogeochemical activity. The results show that shallow deposits--such as those found in arctic regions or in the Gulf of Mexico--can undergo rapid dissociation and produce significant methane fluxes of 2 to 13 mol/yr/m{sup 2} over a period of decades, and release up to 1,100 mol of methane per m{sup 2} of seafloor in a century. These fluxes may exceed the ability of the seafloor environment (via anaerobic oxidation of methane) to consume the released methane or sequester the carbon. These results will provide a source term to regional or global climate models in order to assess the coupling of gas hydrate deposits to changes in the global climate. Other/Unknown Material Arctic Climate change Methane hydrate SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Arctic |
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SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
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topic |
54 ARCTIC REGIONS CARBON CLIMATE MODELS CLIMATES DISSOCIATION DISTRIBUTION GAS HYDRATES HYDRATES INSTABILITY METHANE NATURAL GAS HYDRATE DEPOSITS OXIDATION SATURATION SEDIMENTS SIMULATION SOURCE TERMS |
spellingShingle |
54 ARCTIC REGIONS CARBON CLIMATE MODELS CLIMATES DISSOCIATION DISTRIBUTION GAS HYDRATES HYDRATES INSTABILITY METHANE NATURAL GAS HYDRATE DEPOSITS OXIDATION SATURATION SEDIMENTS SIMULATION SOURCE TERMS Reagan, Matthew Reagan, Matthew T. Moridis, George J. Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change |
topic_facet |
54 ARCTIC REGIONS CARBON CLIMATE MODELS CLIMATES DISSOCIATION DISTRIBUTION GAS HYDRATES HYDRATES INSTABILITY METHANE NATURAL GAS HYDRATE DEPOSITS OXIDATION SATURATION SEDIMENTS SIMULATION SOURCE TERMS |
description |
Paleooceanographic evidence has been used to postulate that methane from oceanic hydrates may have had a significant role in regulating global climate, implicating global oceanic deposits of methane gas hydrate as the main culprit in instances of rapid climate change that have occurred in the past. However, the behavior of contemporary oceanic methane hydrate deposits subjected to rapid temperature changes, like those predicted under future climate change scenarios, is poorly understood. To determine the fate of the carbon stored in these hydrates, we performed simulations of oceanic gas hydrate accumulations subjected to temperature changes at the seafloor and assessed the potential for methane release into the ocean. Our modeling analysis considered the properties of benthic sediments, the saturation and distribution of the hydrates, the ocean depth, the initial seafloor temperature, and for the first time, estimated the effect of benthic biogeochemical activity. The results show that shallow deposits--such as those found in arctic regions or in the Gulf of Mexico--can undergo rapid dissociation and produce significant methane fluxes of 2 to 13 mol/yr/m{sup 2} over a period of decades, and release up to 1,100 mol of methane per m{sup 2} of seafloor in a century. These fluxes may exceed the ability of the seafloor environment (via anaerobic oxidation of methane) to consume the released methane or sequester the carbon. These results will provide a source term to regional or global climate models in order to assess the coupling of gas hydrate deposits to changes in the global climate. |
author |
Reagan, Matthew Reagan, Matthew T. Moridis, George J. |
author_facet |
Reagan, Matthew Reagan, Matthew T. Moridis, George J. |
author_sort |
Reagan, Matthew |
title |
Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change |
title_short |
Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change |
title_full |
Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change |
title_fullStr |
Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change |
title_full_unstemmed |
Modeling of Oceanic Gas Hydrate Instability and Methane Release in Response to Climate Change |
title_sort |
modeling of oceanic gas hydrate instability and methane release in response to climate change |
publishDate |
2008 |
url |
http://www.osti.gov/servlets/purl/935357 https://www.osti.gov/biblio/935357 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Climate change Methane hydrate |
genre_facet |
Arctic Climate change Methane hydrate |
op_relation |
http://www.osti.gov/servlets/purl/935357 https://www.osti.gov/biblio/935357 |
_version_ |
1772812357105352704 |