Dude its called air conditioning, and we can grow the world economy to put it in every hut in africa within the decade if people are free, its impossible to "reverse" the effects havent you heard?
A refresher in thermodynamics is in order here....thermal energy is...energy, which is a conserved quantity. Heat doesn't just disappear. An air conditioner cools the inside air by making the outside air hotter.
And (thermodynamics strikes again) it also creates yet more waste heat in the process.
// if people are free //
Doesn't matter how free people or the markets are, thermodynamics is for real. We are not air-conditioning our way out of this.
Do we also air condition the farms?
Even if that were possible, humanity has shown that we will only do something worldwide when we're absolutely forced to. We will not be able to do that while dealing with the disasters that come with global climate catastrophe and ecological collapse.