bbr2314,
What you seem to suggest (oscillation in the location of the cold pole) would only apply if there were essentially no net warming. But ... there is massive generalized warming. That is why the artic ice is melting - not because of an oscillation about where the cold pole is.
Once the Arctic Ocean ice is gone, Greenland will be the north cold pole. All the heat that has gone into melting the arctic ice will then shift into heating the ocean AND melting Greenland. Greenland is large and the ice is deep. That will take time to melt - perhaps 100-200 years. Hopefully we will have learned something before then as a result of the end of civilization and agriculture. No bet there though. Man hasn’t exhibited any sign of wisdom or learning yet. So I see little basis to suggest mankind will learn from the calamity.
Still, we have some time before the loss of all north polar ice is complete.
Beyond that, it will likely take a millennia to melt off Antarctica. Surely we will learn something before then, or simply die off entirely. In either case, I will be long dead and long past caring. Unless and until we melt off Antarctica we cannot pull off a new Venus - not that that should ever be a goal.
I think you are missing my point. Where we are *today* we are *already* seeing relative cooling in Greenland (even if calving and some SMB loss continue). This is probably due to 1) higher Greenland albedo due to increasing snowfall and 2) the cold pool from all the fresh melt in both Greenland and Canada, which buffers Greenland from the Gulf Stream to some extent.
If we are at 2018, six years after 2012 (worst summer on record) and summertime temps have *dropped* fairly consistently, year over year since then over a specific region -- it is time to consider that the inflection point of 2012 was the flipping switch where we went from "everywhere is getting hotter" to "hold on a minute, most everywhere is still getting hotter, but this specific spot in particular is now becoming colder in terms of temps each years, and the spot itself is now increasing in size to cover the entire Canadian Shield and Greenland".
So what happens when we get to 2024 and the Arctic is still spiraling in terms of volume? Will the trend that has developed since 2011-12 magically reverse and will Canada and Greenland start warming over summertime? Maybe one summer out of the next few sees such a result, but I am banking on the contrary, especially if recent history is any indicator. While Siberia is going to scorch and burn each and every year, Canada is going to be increasingly white come 8/1 each year (and Greenland's melt pulses will be exactly that, I highly doubt it will endure any stretch of multi-month +++ anomalies outside of the times of year where such a result still leaves temps sub-freezing).
It is important to note that as the Arctic's capacity for cooling shrinks, Greenland's is seemingly growing to compensate, as well (both due to albedo and less oceanic heat immediately to its SE). That means as we approach a BOE CAB, Greenland is likely to begin *adding* seasonal SMB, even if calving continues. The side effects of increasing melt in Greenland as much as we already have result in so much cooling thereafter that any GHG reductions etc are already moot and we are doomed.
The notion that Greenland could melt in 100 or 200 years is equally absurd. A mass loss of 1% of the GIS in a single 365-day span would result in the discharge of 28,500KM^3 worth of ice, which is substantially more than the entire Arctic Ice sheet measures at peak volume each winter nowadays. And all that would go into the NATL! We would quickly enter a winter far worse than Tambora's if such an event ever occurred.
For reference: this year it took 800KM^3 of additional SWE accumulated in North America as of ~4/15 (double normal) to result in a severe postponement of summer across most of the Shield, and much of Greenland altogether. Now that is *additional* SWE melt vs. normal (and resulting albedo feedbacks), but consider how *SMALL* that number is, and how BIG the Greenland melt numbers are for full melt, and then realize the implications of what happened this summer mean Greenland meltout is impossible because we entire spiral-snowball NHEM by the time it is down a couple tens of thousands of cubic KM.
PS:
...also did some googling re: Greenland's albedo this yr --
http://nsidc.org/greenland-today/"High winter and spring snowfall, and a moderate initial pace of melting, resulted in a more reflective (higher albedo) surface for the ice sheet than in past summers. Since bright, fresh snow blanketed areas that were once darker, such as dirty snow or bare ice, July’s average albedo for the ice sheet was 5 to 9 percent above the 2000 to 2009 reference period."
Looks like the monthly albedo in July 2018 was about .78, possibly a record high, versus .72 in 2012, a record low. That is about an 8% increase in Greenland's reflectivity. And not only is Greenland getting whiter, the Arctic is still blue-ing and maybe has a bit more snow parts of the yr but by August, even this yr went snow-free. The contrast is worsening, but as Greenland keeps getting whiter and snowier (in fact according to NSIDC ^^^ this year had a SMB gain, even accounting for calving), its potency for generating PVs / Greenland airmasses will only grow stronger.
It must also be noted the biggest differential in Greenland's albedo vs. recent norm in 2018 was at a time of peak insolation. This is especially consequential because during wintertime, Greenland is mostly dark anyways. But an 8% difference in reflectivity over an area the size of Greenland in only six years is enormous! The forcing from the albedo differential is now overwhelming GHG input (or rather rising because of it, due to all the snow).
Assume Greenland keeps getting snowier through 2030. Is it unreasonable to expect albedoes rising upwards to 85-90%? What happens to temps then? The potential surely matches well with the extremely abrupt drops seen historically.
And a final note from NSIDC re: 2018 --
"As noted in the previous post, exceptional winter snow accumulation and heavy, summer snowfall, drove the net snow input mass to 130 billion tons above the 1981 to 2010 average. This was followed by a near-average melt and runoff period, resulting in a large net mass gain for the ice sheet in 2018 of 150 billion tons. This is the largest net gain from snowfall since 1996, and the highest snowfall since 1972. However, several major glaciers now flow significantly faster than in these earlier years. The net change in mass of the ice sheet overall, including this higher discharge of ice directly into the ocean, is not clear at this point but may be a smaller loss or even a small gain. This is similar to our assessment for 2017, and in sharp contrast to the conditions for the preceding decade."
