When I wrote Threshold, I lived in the Sonoran Desert in Tucson. Later I moved to the Gulf Coast of Florida. Both places are hot and getting hotter. Too little water or too much water are the respective outcomes for these distinct regions in the United States on the Fourth of July.
When I was writing Threshold, climate change science was rapidly developing but still considered the domain of zealots.
The fact that the Earth is warming is indisputable. The average increase between 2009 to 2018 was 1.34 degrees Fahrenheit. While that may seem small this is a complex figure calculated from average temperatures across the planet, from very cold to very hot. Total surface area of the Earth is billions of square meters. For the average temperature to rise takes a huge amount of energy.
Humans being the complex species that we are, we ignore signs of impending problems when we feel unable to do anything about it. We stick our heads in the sand. That response spells trouble for us.
Read a review about Threshold, then pick up a copy. Its worth the study of how various people react and respond. The book is not a dystopia but a realistic look at how I believe the near future might unfold based on my experience.