Warm waters from Greenland are accelerating the warming of the deep Arctic, which were thought to be “safe” from the climate crisis.
The last bastion of ocean that we thought was affected by the climate crisis is warming. The deeper waters of the Arctic Ocean (also known as the Arctic Ocean) are experiencing a temperature increase driven by the rapid warming of the Atlantic.
It was long believed that any upward swing in the heat of these waters was attributable to geothermal springs, but a study published in Science Advances discovered that it is actually the warmer water coming from nearby Greenland that is promoting warming in the depths of the Arctic.
This hitherto hidden excess heat could in turn contribute to a further reduction of sea ice or even the melting of underwater permafrost, a phenomenon so far unrelated to global warming, which has been proceeding slowly and naturally since the end of the last glacial period, 14,000 years ago.
Suspicious increase
After verifying that in some deep areas of the Arctic the rate of warming was faster than simply justifiable with geothermal heat, scientists from the Ocean University of China and the Laoshan Laboratory (China) decided to analyze decades of data on Arctic water temperatures collected by icebreakers, to measure the extent of warming coming “from below” (and not from the atmosphere).
The waters that warmed most rapidly were those of the Eurasian basin, one of the two major basins in which the Arctic Ocean is divided by an imposing underwater mountain chain, the Lomonosov Ridge. The waters between 1,500 and 2,600 meters have warmed by 0.074 °C since 1990. It seems little, but – as the New Scientist – is the temperature increase corresponding to the transfer of almost 500 trillion megajoules of energy, which if they reached the surface, could melt a third of the sea ice at its minimum annual extent.
Influence of warm waters
For researchers, the origin of the increase in temperatures at these depths would be the northward rise of warmer waters coming from the Greenland basin, once the main supplier of freezing waters to the Arctic Ocean and now subject to warming so rapidly that it is no longer able to carry out this task.
The result is that less cold waters than usual are infiltrating the Eurasian basin, which is favoring an increase in temperatures even at depth. The Lomonosov Ridge shields the other basin into which the Arctic Ocean is divided, the Amerasian one, which is apparently warming less rapidly, from these intrusions.
In short, the warming of the Greenland basin has spread to the deep Arctic.
Yet another, unexpected target of global warming.