This means SOLAR ALTITUDE just isn't high enough until the first week of June to overcome albedo.
This means we well have to see background temps warm likely another 2-4C around the ice in May and snow cover to vanish at least a week earlier than the current earliest before we see ice volume sustainably go lower than it already has.
This means a total melt out isn't likely until 2035-2040 or later
Interesting idea. Wouldn't the amount of cloud cover and melt ponds during the period of roughly late May to the third week of July be more significant factors that determine higher latitude melt out, rather than air temperature? Mainly by increasing the amount of solar energy that gets through the ice and then does most of the overall melting by bottom melt. I was under the impression that bottom melt did a larger proportion of the melting over the course of the melt season, rather than warmer air over the ice. My assumption is that lot more energy is transferred into the system from sunlight into water than is transferred in via warm air over ice.
Maybe I'm misreading what you're saying? Maybe you're saying that we need 2-4C temperature increase in order to achieve early enough preconditioning and melt ponds to allow enough solar energy through the ice to achieve total melt out above 80 degN?
If so, a normal summer until then would see ice melt rapidly at lower latitudes, but generally stall around 70-80 degN?
Unless there is an unusually sunny period between the last week of May and the third week of July, in that case the melt out might go a lot further north.
That's exactly right.
Solar altitude doesn't get high enough to overcome the snow albedo effect until the first week of June.
We had 4-5 days in a row of 24 sun over large parts of the basin between 75-90N.
And albedo did take a hit but only a little bit.
The full wetness look on satellite never materialized.
And once temps slightly cooled and sun vanished the surface froze back up.
And yeah for bottom melt direct solar insolation is required.
But warm air advection can ravage the surface way now than sun because the solar ALTITUDE always sucks North of 70.
I live at 38.75N in the United States.
And right now the sun during peak heating is almost directly overhead.
A couple days ago we had very strong CAA... Temps were in the mid to upper 50s which is currently about 20-23F below normal.
We had low level cumulous clouds rotating in from the NW.
It was a very cold day. Or felt cold considering what time of year it is.
Well the cumulous deck covered about 65 percent of the sky.
And when the sun would peak out it instantly felt like the gates of hell were breathing fiire down on your skin.
In January when its 50F under the same conditions.
And the sun breaks out you feel essentially no difference on your skin.
It doesn't start becoming very noticeable until early February.
By March is very noticeable.
Anyways solar altitude between 80-90N barely goes above 25° and I believe at the pole it never rises above 23.5° but I may be incorrect about that.
My point is to melt out the 3M+ MYI in the CAB we will definitely need big time dipole sun in June/July.
But also great preconditioning.
It would help immensely to see snow cover over the CAA be essentially gone by June 1st.
And then we would need not just sun. But a HP/SLP set up that brings a surface wind fetch that origionates West and Northwest of the Hudson Bay over the last lands of Canada.
This allows the low level air mass to heat up dramatically more than a flow either over the Hudson Bay, East of there over the Baffin and CAA waterways, or West over the Beaufort or Western CAA waterways.
This route if it could become established for more than a couple days could be devestating to the CAB.
In late July 2012 a similar set up took place between July 29-Aug 4th.
It completely destroyed a large part of the Western CAB.