text: Research carried out in 2008 in the Siberian Arctic showed methane releases on the annual scale of millions of tonnes, which was a substantial increase on the previous estimate of 0.5 millions of tonnes per year.  apparently through perforations in the seabed permafrost, with concentrations in some regions reaching up to 100 times normal levels. The excess methane has been detected in localized hotspots in the outfall of the Lena River and the border between the Laptev Sea and the East Siberian Sea. At the time, some of the melting was thought to be the result of geological heating, but more thawing was believed to be due to the greatly increased volumes of meltwater being discharged from the Siberian rivers flowing north. 
  By 2013, the same team of researchers used multiple sonar observations to quantify the density of bubbles emanating from subsea permafrost into the ocean (a process called ebullition), and found that 100–630 mg methane per square meter is emitted daily along the East Siberian Arctic Shelf (ESAS), into the water column. They also found that during storms, when wind accelerates air-sea gas exchange, methane levels in the water column drop dramatically. Observations suggest that methane release from seabed permafrost will progress slowly, rather than abruptly. However, Arctic cyclones, fueled by global warming, and further accumulation of greenhouse gases in the atmosphere could contribute to more rapid methane release from this source. Altogether, their updated estimate had now amounted to 17 millions of tonnes per year. 
  However, these findings were soon questioned, as this rate of annual release would mean that the ESAS alone would account for between 28% and 75% of the observed Arctic methane emissions, which contradicts many other studies. In January 2020, it was found that the rate at which methane enters the atmosphere after it had been released from the shelf deposits into the water column had been greatly overestimated, and observations of atmospheric methane fluxes taken from multiple ship cruises in the Arctic instead indicate that only around 3.02 million tonnes of methane are emitted annually from the ESAS. A modelling study published in 2020 suggested that under the present-day conditions, annual methane release from the ESAS may be as low as 1000 tonnes, with 2.6 – 4.5 million tonnes representing the peak potential of turbulent emissions from the shelf.