Modeling the climate response to a massive methane release from gas hydrates

• Published in: Paleoceanography
• Main Authors: Renssen, H., Beets, C.J., Fichefet, T., Goosse, H., Kroon, D.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2004
• Subjects: Sea ice
• Online Access: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=211450

[1] The climate response to a massive release of methane from gas hydrates is simulated in two 2500-year-long numerical experiments performed with a three-dimensional, global coupled atmosphere-sea ice-ocean model of intermediate complexity. Two different equilibrium states were used as reference climates; the first state with preindustrial forcing conditions and the second state with a four times higher atmospheric CO 2 concentration. These climates were perturbed by prescribing a methane emission scenario equivalent to that computed for the Paleocene/Eocene thermal maximum (PETM; similar to 55.5 Ma), involving a sudden release of 1500 Gt of carbon into the atmosphere in 1000 years. In both cases, this produced rapid atmospheric warming (up to 10°C at high latitudes) and a reorganization of the global overturning ocean circulation. In the ocean, maximum warming (2-4°C) occurred at intermediate depths where methane hydrates are stored in the upper slope sediments, suggesting that further hydrate instability could result from the prescribed scenario.