Effect of climate change on the marine methane hydrate stability zone

• Main Author: Fyke, Jeremy Garmeson
• Other Authors: Weaver, Andrew J.
• Format: Thesis
• Language: English
• Published: 2005
• Subjects: marine sediments; gas content; climatic changes; UVic Subject Index::Sciences and Engineering::Earth and Ocean Sciences; Methane hydrate
• Online Access: http://hdl.handle.net/1828/1851

The marine gas hydrate stability zone (GHSZ) is sensitive to climatically driven temperature changes at the seafloor. This thesis reviews past studies of the GHSZ response to climate change, and presents the results of a numerical analysis of a marine gas hydrate stability model forced by an intermediate complexity climate model. Potential future climate scenarios are simulated. resulting in realistic predictions of seafloor temperature change over variable bathymetry. The average continental margin seafloor temperature increase is greater than the global seafloor average. and it is determined that even for CO2 concentrations held below present-day levels. the global GHSZ will decrease significantly. The experiments carried out here indicate that after 40 kyr the GHSZ volume will shrink by between 1% and 29%. based on various CO2 scenarios and parameterizations of thermal diffusivity and geothermal gradient. Regions which exhibit 100% GHSZ loss range from 1% to 9% of the prescribed continental margin. Results of this study suggest that the effects of future GHSZ loss may be felt by the exogenic carbon cycle within centuries and last for tens of thousands of years.