Global warming / climate change. If it’s happening, it could literally be the end of the world, as we know it. For nearly 10,000 years the Earth’s climate has been stable in a way advantageous to humanity. There have been aberrations, but always a return to a favorable mean. If that is changing, then we better be ready in several areas.
Weather: Summers may be hotter but winters might be colder, too, if the jet stream shifts and brings Arctic air southward, or the Gulf Stream stops flowing. And increased moisture and energy may make storms more violent and larger, the weather unpredictable. Climate change means precisely that; the climate is changing.
Food Production: The massive quantities we get from modern agriculture require petrochemicals, water, and a stable environment. If climate change leads to disruptions in supply and increased demand, and crop failure because the weather is too hot, too cold, too dry, too wet, etc, it is possible food could become scarce and very expensive.
Infrastructure and Power: Roads, dams, power lines, everything man-made has limits. The infrastructure of the U.S. is already weak; environmental stress will make things worse. Movement of supplies and people, and transmission of power, are vital and will need to increase if repair is necessary. Should that movement be slowed and the power grid fail just when they are needed most, it could be disastrous.
Coastal areas and shipping: The sea is rising by two to four millimeters a year, National Geographic reports . That’s small but the cumulative effects can be huge. Already some cities are having troubles. It may come to building dikes around coastal cities or relocating them, at great fiscal and human cost. And, as most international trade is handled via shipping, and rising waters may make current seaports unusable, it is possible the flow of goods will be stopped.
Ecological Disruption: Polar bears are in trouble. Other species are having problems. It is not hard to envision a slow but growing cascade of change as temperatures become more extreme. Mankind has never had to deal with a global ecological disaster. It may be beyond our capacities.
Human health: Most diseases don’t do well in cold weather. Cold and Flu Season is more due to increased contact from hours indoors during winter than reduced temperature. But a rise in global warmth, a change in the ecology: Some diseases are on the cusp of being dangerous to humans but haven’t made it on their own. A small push might be all they need. And people suffer now from weather extremes; if those become worse, the toll in human life, and the costs of trying to preserve it, may become severe.
Economic Costs: Huge costs to maintain function, lost profits, money spent to save lives. Many nations aren’t going to be able to handle the expenses that could be coming. Some may go bankrupt, unable to provide essential services. Citizens will become angry, governments may fall and be replaced by those promising to fix things. And that may lead to
War: The above paints a world in which nations and peoples are suffering. And when humans are suffering they may try to alleviate it by taking from others. It is not hard to imagine warfare for still arable cropland, water, oil, necessary resources. And as the more developed nations consume a major share of the Earth’s resources, they may be both aggressors AND targets.
War, famine, pestilence, and death. Global warming may not be the Apocalypse. But it might be close enough.