If deeper snow means longer lasting snow, there are albedo effects, though of course difficult to quantify compared to all other effects. But the question I am interested in is whether deeper snow (esp. In famed Quebec) actually means longer-lasting snow. A database is hard to come by, but I plan to have some small result of my "research" next week.
Fantastic!
Also, I disagree re: SE Canada.
I think Quebec is unique among Northern Hemisphere landmasses as it is most proximate to Greenland. When sea ice collapses (as has been the case most recent summers), the worse it gets, the more often the winds switch to easterly, allowing plumes of Atlantic moisture to drift over the ice sheet and exit the lee side, spilling over Quebec and Baffin Bay.
This unique geographic situation mitigates the relative middling latitudinal situation by anchoring Quebec with a cold source second only to Antarctica in capabilities. More importantly, the less sea ice there is in the Greenland Sea/near Svalbard, the more prone Greenland is to unloading its heat-bearing capabilities onto Quebec/Baffin (i.e. "-NAO").
I think this mechanism is separate from the heat-loading in the NW NATL, which (IMO) is chiefly responsible for the wintertime snowfall + anomalies.
While ridging into Greenland can also force residual resolution of the heat (i.e., cold) into Europe, the Atlantic modifies these airmasses significantly. Quebec sees no such modification, especially when Baffin is fully iced.
The ice has taken a massive beating across St. Lawrence/near Newfoundland as many others have noted, but I believe Baffin Bay is in the midst of importing the thickest first year and multi-year ice it has seen in many years. It is possible that this acts in tandem with the anomalies in Quebec to delay melt by many weeks, possibly even a month or two.
The 12z EURO shows why Quebec's persistence will have impacts into April and May. The above map shows COLD over all of Eastern North America even though the absolute anomalies are very warm in Quebec and very cold in the Northeast.
The substantive & extensive snowpack across the Northeast/Ontario should serve to buffer Quebec from any heat for the foreseeable future, well into April. It is quite possible in my opinion that we see North American SWE anomalies extend upward once more (historically speaking, there are two maxes). The late & continual unloading of SWE into the NATL may have a very substantive effect of buffering Baffin further against melt.
The question is how long they sustain into spring. My guess is we don't fall below 1,000 KM^3 until 5/1 or later. If that is the case, the differential re: albedo becomes.... VERY major, especially if we extend into June. Not only is this substantial because of how irregular it is vs. normal, but because the background state elsewhere is so much warmer (if Quebec is as cold or colder than normal into early summer, and the NW NATL is warmer than ever, heat resolution is going to result in more powerful LPs than ever before as well).
This perhaps explains why Hansen's storms of yesteryear are borne into fruition and also would be reasonable cause for the rather unprecedented March cold/snow across large portions of the populated NHEM (Northeast US, Europe particularly). This could also have major implications for Greenland and Arctic melt as we move forward (in snyc with what is occurring across Siberia and Okhotsk).
I anticipate we will see the formation of three persistent and dramatic cyclone engines in the vicinity of Newfoundland's eastern waters, the gap between Iceland & Scandinavia, and Kamchatka, as we move forward in the year. The overwhelming SSTA in the mid-latitudes in sync with these ridiculous snowfall anomalies (i.e., capable of supporting cold!) should make for a substantially more efficient resolution of atmospheric heat, and in the absence of a regular jet stream due to the worsening land/ocean gradient, this will take the form of massive cyclonic transport.
Fun times await!