Signs of instability

Abstract

The finding that pools of gas hydrates — compounds that trap natural gas emissions — in ocean sediments are deeper than expected implies that the hydrates are destabilizing, and might release gigatonnes of methane. See Letter p.527 Clathrates store enormous amounts of methane, much of it in shallow ocean shelf environments. It has been proposed that sudden methane release from clathrates could cause abrupt climate changes, and this has been invoked to explain past warming events such as the Paleocene–Eocene thermal maximum. Clathrate destabilization in the modern climate is possible, especially in cases of pronounced ocean warming. Here, Benjamin Phrampus and Matthew Hornbach use seismic data and modelling to reveal clathrate destabilization along the United States Eastern margin. The destabilization is thought to be linked to warming of the Gulf Stream, or to a slight shift in its position. The climatic impact of the methane released by clathrate destabilization remains uncertain, however, because it is not clear how much of the methane would actually enter the atmosphere.