I live in Edmonton, Alberta, so winters usually last between late October until mid April. They are dark and grey, usually hovering around -15C.
In Keuruu, located in Middle Finland, the average winter temperature has been -7 to -10 C during recent decades. Summers are normally relatively cool, 14 to 16 C, but recent summers have been warmer, except this year. GW is estimated to affect Northern latitudes more than others, so the cold probably won't be a problem for you. (I'm more concerned about forests not being able to adapt quickly enough to a rapid warming.)
I don't want to be in Canada for the simple reason that 90% of our population lives within 100 miles of the American border. Where will 300 million people go when TSHTF that: is sparsely populated, close geographically, filled with resources, speaks the same language, governs with roughly the same laws and are spineless in their countries defense (as shown through the takeover of roughly 13,000 Canadian corporations since NAFTA was signed in the 1980s)
By the time the US really needs to attack Canada, if the US government ever decides for such a desperate move at all, its ability to wage war will be much weaker (supposing that there are enough soldiers willing to attack a peaceful neighbor just to grab its resources). The costs of a massive ground war would probably outweigh the benefits of grabbing the ever-shrinking NG resources and the tar sand mines. And even when TS has HTF, not that many Americans may be mentally or physically prepared to trek very far north for plundering raids. Refugees might be another matter.
Besides, climate change is estimated to favor Canada in the foreseeable future (more crops, less energy needed for heating) so I wouldn't discard your native country as an option.
Being close to Russia is Finland's only downside.
OTOH, it also means being close to the largest NG resources in the world and very large coal deposits, too. As long as we have something to trade for it, or find some other way to remain useful for the bear.
The worst downside here is dependence on the Gulf stream, but most recent research doesn't show its shutdown likely in the coming decades.
If Finland slips into poverty
100% certain (as everywhere).
and I happen to be in a major city other than the ecovillage
Not unlikely, given that a small ecovillage in the backwoods may become unviable at some point during the great recession. (I suspect they get some kind of government support now.)
In fact, you could have better chances if you settle in a city/town and have or acquire some practical skill like plumber, electrician, carpenter or tailor. People without applicable skills (like me right now, unless I get a permanent teaching job or find suitable training in a practical trade) are likely to end up unemployed or become a wood-chopper with a pay barely above starvation level. (The way things are going globally, I'd be content even with that.)
there is a good chance I will be politely (or not so politely)
asked to leave despite my citizenship (my last name is NOT Finnish but Danish so there is a possibility I could be rooted out).
Unlikely. I just don't see us becoming a fascist state where people are rooted out because of their surnames, especially if they're citizens. Racism is a problem in some remote places, and may become more common, but it usually affects only differently colored people, not people of Scandinavian origin.
If a resident foreigner is willing to work hard and adapt to the circumstances, there's no reason to kick them out.
