Methane gas seeps from seabed outside Svalbard
A scientific study shows that the powerful greenhouse gas methane is escaping from the Arctic seabed. This could be a response to climate change and higher ocean temperatures and accelerate climate changes even more.
A research team led by the National Oceanography Centre in Southampton has found that more than 250 plumes of methane bubbles are rising from the sea-bed off Svalbard, Aftenposten writes.
Methane released from gas hydrate in submarine sediments has been identified in the past as an agent of climate change. The likelihood of methane being released in this way has been widely predicted.
-We already knew there was some methane hydrate in the ocean off Svalbard, but we did not expect to discover such strong evidence that this process has already started, Professor Tim Minshull of the National Oceanography Centre says.
The reason for the escape of the methane gas is the increased temperature in the waters around Svalbard. The gas is normally trapped as “methane hydrate” in sediment under the ocean floor. This ice-like substance is composed of water and methane and is stable under conditions of high pressure and low temperature. Temperature records show that this area of the ocean has warmed by 1°C during the last 30 years, the National Oceanography Centre writes on their web site.
Most of the methane reacts with the oxygen in the water to form carbon dioxide, another greenhouse gas. In sea water, this forms carbonic acid which adds to ocean acidification, with consequent problems for biodiversity.
If this process becomes widespread along Arctic continental margins, tens of megatons of methane a year - equivalent to 5-10% of the total amount released globally by natural sources, could be released into the ocean, the scientists warn.
