What do you know today that you didn't know yesterday?

[GrandizerII]

So cut down forests and turn them into arable lands and this effectively combats climate change is what you're saying?

Yes, other than relocating some people from islands in Pacific Ocean there is no real economic harm.

So two problems you're not noting here:

Not all countries contain boreal (or other cold enough) regions that you naively believe can be made arable with warmer temperature. And even in countries that do, that may be a small percentage. IOW, how is Canada going to be of much help to countries, say, along the Equator?

To be arable, there needs to also be adequate supply of water. IOW, not so dry as to not be able to promote food growth.

I know there are a lot of other factors involved that you're missing/overlooking, but I'll let the more knowledgeable people expound on those.