too much heat is a much bigger problem for life on earth than too much cold

 This is especially true of mankind partly because when you generate electricity for Air Conditioning you create a lot more heat doing this running the coolant and sucking the heat out of areas. So, by generating the electricity and running the air conditioners you are actually creating more heat than you had before.

I suppose you could be underground where it often stays cooler but you still need to have fresh air there too so you might run your fans replacing the air during the coolest part of the night and then breathe that are at around 60 degrees most places underground during the rest of the next day and then not need air conditioning too. There are many ways to solve the problem individually and family wise.

However, since most people are not educated enough to understand all this themselves unless someone more educated tells them, many people who cannot or will not listen to someone more educated than themselves are likely going to die this summer and fall.

It strange to me that cold problems are easier to solve than hot problems. 

For example, mankind likely survived the ice ages simply by migrating towards the Equator more as it got colder further north (or they built igloos) like the Native Americans in Alaska and northern Canada did too.

But, either way problems regarding cold are easier to solve (with an igloo in the ice) for example as long as you didn't raise the temperature above about 50 degrees in the igloo and start melting the ice Igloo.

Heat becomes a problem but animals around the world often deal with this problem by burrowing into the ground like squirrels and Go downs and other animals and even raccoons and bears and other animals burrow into the ground to keep cool as well as warm different times of the year.

Likewise, humans may start having to do this more too just to survive the hotter summers and falls around the world too.

Another way this problem is solved is ONLY working when it is dark and sleeping when it is hot outside. 

For example, in places like the Deserts of California, Nevada, Arizona and Texas and New Mexico often people who have to work outside like Linemen or people who work on the road ONLY work at night and sleep during the day already in multiple states in order to prevent heat stroke in these states in the summer and fall of any given year.

So, I think more and more people will be forced by necessity to work nights and sleep days instead to stay cool enough to prevent heat stroke now all over the world.