Ah! I think what that article is trying to say is that when you have a greater variance in temperatures, any change is going to be something that is more regularly tolerated. E.g. - imagine you add 5 degrees of temperature to an area that varies between 20 and 100 degrees throughout the year, spending only 10% of the year at temperatures above 95 degrees. That means during 90% of the year there would be no change in temperature that has not already been seasonally experienced for centuries. By contrast if you do the same to a country that spends 100% of the year at 98 degrees, then adding 5 degrees would have a consistent 0-variance impact all year long above anything ever experienced. Since there's the least variance in the seasons at the equator (due to Earth's axial tilt) they then suggest that climate change will thus affect the equatorial regions the most.

But I think this is a gross simplification that again gets into the thinking that the temperature is, in and of itself, the problem. It's not. The global climatic system is in an equilibrium. At any given point in the sea for instance the difference between ice and water is the slightest change in temperature. Bump up the temperature a few degrees and that equilibrium radically shifts. This, in turn, can have cascading effects. It doesn't matter that in one location it's now only e.g. 65 when they have heat that goes up to 100 degrees during their summer. It's not about the heat - it's about the ancillary global effects of that change in heat levels, that will affect everywhere. This is one of the many reasons that I think the change in terminology from "global warming" to "climate change" was extremely appropriate. Global warming is not a problem, but the climatic effects it causes may be.

Our micro-level predictions for climate change have so far been pretty awful, but our macro-level predictions have been decent. So I think it's more reasonable to look at the 'big picture' effects, like rising seas. When you get into micro predictions you get silly things. This [1] is an article from AP:

"A senior U.N. environmental official says entire nations could be wiped off the face of the Earth by rising sea levels if the global warming trend is not reversed by the year 2028. Coastal flooding and crop failures would create an exodus of ″eco-refugees" threatening political chaos, said Noel Brown, director of the New York office of the U.N. Environment Program, or UNEP. He said governments have a 10-year window of opportunity to solve the greenhouse effect before it goes beyond human control. As the warming melts polar icecaps, ocean levels will rise by up to three feet, enough to cover the Maldives and other flat island nations, Brown told The Associated Press in an interview on Wednesday. Coastal regions will be inundated; one-sixth of Bangladesh could be flooded, displacing a fourth of its 90 million people. A fifth of Egypt’s arable land in the Nile Delta would be flooded, cutting off its food supply, according to a joint UNEP and U.S. Environmental Protection Agency study."

I changed the date there. That article is from 1989. The real catastrophe deadline given was 2000, 18 years ago.

[1] - https://apnews.com/bd45c372caf118ec99964ea547880cd0