It's like you don't know anything at all about this. Warming does not occur uniformly over the planet. The warming occurs disproportionately in the polar regions. It's warming in the higher latitudes which drives the rise in average temperature.Is that going to make up for all the dead crops around the equator? You're going to lose more than you'll gain. Simple geometry. And they'll be no increase in the sunlight at those northern latitudes.