Even if we manage to reduce CO2 in the atmosphere, for the next centuries (or millennia) the temperature of the Arctic will be 1.5 °C higher than pre-industrial levels. This is the not very comforting conclusion of a study published in Environmental Research Letters which confirms what has also been found by other research on the topic: at least in the short term, Arctic warming appears to be largely irreversible.
Three scenarios. To reach these conclusions, the researchers used 11 independent climate models which they asked to predict the evolution of Arctic warming based on three scenarios: one purely theoretical and two more realistic ones. In the first (unachievable) case, CO2 concentrations quadrupled compared to pre-industrial levels for over 140 years, then decreased for another 140 and finally stabilized at pre-industrial levels for 60 years. In the other two scenarios, considered plausible, an immediate cut to CO2 emissions and one starting from 2070 were hypothesized.
+ 1.5 °C. Even if the climate terms change, the results returned by the models are the same: even with drastic carbon reduction measures, the temperature of the Arctic would still stabilize around + 1.5 °C above pre-industrial levels (we are currently at +3.3 °C). On top of that, by 2100 the region would continue to receive about 0.1 millimeters more precipitation per day. The main reason is the inertia of the ocean, which absorbs about 90% of the excess heat generated by global warming and will continue to slowly release it, keeping the Arctic warm for centuries even after a possible cooling of the atmosphere.
Against the current. According to climate models, however, there is an exception: a band of the North Atlantic, just south of Greenland and Iceland, could cool and become drier, in contrast to the rest of the Arctic. The phenomenon would be linked to a weakening of the AMOC (Atlantic Meridional Overturning Circulation) current system, which will transport less warm water from the tropics towards the North Atlantic.
According to the study, Arctic warming would therefore be irreversible, but only “momentarily”: within several centuries or even millennia, the researchers explain, the region should finally cool.
