It’s happened. An early-season Scandinavian heatwave has pushed above freezing temperatures all the way into the central Arctic.
A powerful atmospheric blocking pattern that spawned record 80+ degree temperatures in Scandinavia this weekend has elongated, stretching all the way into the central Arctic. As the bulge increased in amplitude, it brought warmer air with it. Temperatures at the North Pole over the past week ranged from 5-10 degrees Fahrenheit. Now, we are seeing temps around 33 degrees, a range of ‘warmth’ usually reserved for mid summer.
You can see the culprit of this warm air injection on the map below. Note the large bulge in the Jet Stream appearing over Scandinavia and reaching all the way to the North Pole:
(Image source: California Regional Weather Service)
This pulse of warmer air is now riding over regions where sea ice was thinned by a persistent, moderate-strength Arctic cyclone that lasted for about a week. The cyclone churned and dispersed the ice, causing large cracks to form even in a region very close to the North Pole. The freezing point of sea water is about 29 degrees Fahrenheit, so we’ll have to see if this warmer air combined with near constant sunlight has any further melting effect (see The Big Thin Begins to learn more about this event).
You can see these above -freezing temperatures running up over Svalbard and on to the North Pole on the map below. Note that temperatures displayed here are in Celsius, not Fahrenheit:
(Image source: Uni-Koeln)
Particularly interesting is that 40 degree F reading on the northeastern tip of Greenland. But the high 30s and low 40s blanket Svalbard as well.
Weather forecast model maps show this pulse of warm air persisting through tomorrow. Then colder air returns along with stormier weather.
A related feature is the persistent cyclone that chewed away at the central ice for much of last week. It has now transitioned to the Beaufort Sea where it appears to be strengthening. Intensification is expected to continue through tomorrow. Then, the cyclone is projected to swing back to the Central Arctic by late Tuesday, apparently feeding on warmer, moister air as it intensifies to a 980-985 mb low by early Wednesday.
(Image source: ECMWF)
Longer range forecasts show the cyclone persisting as it continues its strange dance around the Central Arctic.
We’ll have to watch the ice pack for further breakage and fracture from these two events. A continued thinning of the central ice so early in the year would be unprecedented. Yet it seems possible enough to continue monitoring.
It’s worth noting that CICE model forecasts show the thickest sea ice just north of the Canadian Arctic Archipelago suffering a sustained thinning. This event, should it arise, would likely be the result of this persistent cyclone combined with intensifying warm air pulses:
(Image source: US Navy CICE)