Although I laud your concern over "massive human suffering", I'm not sure I understand what you mean by that. Are you referring to an apocalyptic event? An event of great urgency?

What I mean is that telling me of a possibly distant future utopia age is of no reassurance when in the more near future people are to suffer often on a massive scale.

The urgency has come into play because that slow, incremental slide down the slippery slope has at last brought its impacts home to a large number of people in the form of frequent and more severe hurricanes, drought, wildfires, glacier melting, famine, etc. And it most definitely is happening in our lifetimes. Today in the news are multiple stories about farmers in the Midwest US who are unable to plant their corn crops because their fields are standing in water due to the changing climate and more severe weather patterns.

I don't know of anyone who sees climate change as a single event. I'm curious where you draw that from. You also say, "sudden ruination of the planet or worldwide flooding". Again, I have not seen or heard of anyone building Noah's Ark v.2 because of climate change. Climate change exhibits in many forms; yes, regional flooding in some geographies is one of them, but there are many others. Worldwide famine may be one of the more cataclysmic outcomes, but even that wouldn't happen suddenly.

Prof Tim Benton, at the University of Leeds, said the new work is based on national US data, rather than farm-level studies, and provides a useful overview. “It captures the big picture,” he said, adding that livestock is the key to the sustainability of global agriculture.

“The biggest intervention people could make towards reducing their carbon footprints would not be to abandon cars, but to eat significantly less red meat,” Benton said. “Another recent study implies the single biggest intervention to free up calories that could be used to feed people would be not to use grains for beef production in the US.”

58:2.2 (665.5) The earth’s atmosphere is all but opaque to much of the solar radiation at the extreme ultraviolet end of the spectrum. Most of these short wave lengths are absorbed by a layer of ozone which exists throughout a level about ten miles above the surface of the earth, and which extends spaceward for another ten miles. The ozone permeating this region, at conditions prevailing on the earth’s surface, would make a layer only one tenth of an inch thick; nevertheless, this relatively small and apparently insignificant amount of ozone protects Urantia inhabitants from the excess of these dangerous and destructive ultraviolet radiations present in sunlight. But were this ozone layer just a trifle thicker, you would be deprived of the highly important and health-giving ultraviolet rays which now reach the earth’s surface, and which are ancestral to one of the most essential of your vitamins.

What do you think this reference means? If the ice caps melt are we going to have another glacial age? Did I read that right?