+2.7C per decade is Monstrous. It is more than 10X the rate of increase in NASA GISS (and other) measures of global average surface temperature. At risk of being one of those alarmists, +2.7 per decade looks like a possible break out from system equilibrium into scary out-of-control realignment to an entirely new climate regime. Maybe the fact that it is an October-only single-region value, and not the whole year/whole planet is some cause for not seeing this as an unfolding catastrophe. If it was a whole year planet-wide rate, we would be into Mad Max territory. Somebody who actually studies this stuff can correct me if I'm wrong, but +2.7C per decade (he says for the 3rd time in one paragraph) is absolutely nuts and unsustainable within the Holocene climate envelope upon which Human civilization is built and dependent. At that rate, the Laptev bite is going to be the CAB bite sooner than any of us ever foresaw.
Some people play fantasy football, I play nightmare planet by tracking NASA GISS and daily Climate Forecast System reports. Entering 2020, my magic predictive formula (which has been more accurate than UK Met and NASA GISS's Gavin Schmidt's prognostications over the last few years) called for 2020 to be several points (0.01 C units) below 2019, due to a weak ENSO signal and coming off of the bottom of the solar cycle. But as 2020 winds down, the current end-of-year-average projection has a 95.8% chance of beating 2019, and a 68% chance of topping 2016, the previous record-holder for warmest yearly global average surface temperature. Keep in mind that 2016 had a strong ENSO and a solar maximum pushing it up. The graph below shows the annual average GISS with ENSO/Solar/Aerosol forcings removed to see the underlying temperature without variation due to single-year forcings. (Too bad Tamino is not posting these days, it would be great to read his take on this).
The last time I sort-of looked, it was hard to see a correlation between annual GISS and ASI Extent/Area/Volume values. Of course, warming the planet as a whole eventually shows up in the Arctic. With La Nina kicking in for the next few months, that should put the brakes on GISS increase over the next six months at least, but I have no clue if that would show up in the Arctic or in the ASI stats. Remember that a cool La Nina year does not mean the Earth system is cooling, just that more heat is going into the ocean vs. the surface atmosphere than in an ENSO-neutral or El Nino year. Heat in the ocean has a bad habit of melting ice.
Looking ahead to 2021, based on the ENSO/Solar/Aerosol predictors, the GISS surface air temperature should be slightly cooler than 2020. But that is from the formula (that explained >80% of year-to-year variability... until 2020) that said 2020 should be cooler than 2019. The fact that my previously reliable formula failed in 2020 feeds my wonderings if Earth's thermostat is broken, and that the climate system is playing by new rules.
As for right now, the DMI 80N temperature is starting to look like the winter of 2016-2017 when there was a low accumulation of freezing degree days. Going out on the limb of my ignorance, I'll hazard a guess that for the near term at least, the recent above-average increases in Extent and Area could lose some momentum. If that DMI anomaly does not fall, it is easy to imagine a new record low maximum in spring 2021.