Global warming: Are we doomed? A poll.

[Alan V]

The very best case scenario out of Cop26, ie if countries quickly implement the stuff they've pledged to promise to think about implementing a strategy into looking at possibly ruminating on ways to begin to start doing, we're looking at 2.4 degrees Celsius rise in temperatures globally before the end of the century.  That's mass extinction level climate change right there.

By the 2100's humanity is going to be reduced to, at best, a few small bands of nomad barbarians eking a subsistence out of the very dangerous ruins of the world.

Climate change is a huge but very slow-moving problem. Oceans will likely take centuries to rise. Feedback mechanisms like the melting of permafrost likewise will take time. The problem is that once these effects begin, they will be very difficult to stop. But as climate scientist Jerry Mahlman said, “There is no need to exaggerate the problem of climate change; it is bad enough as it is.”

A business-as-usual scenario, in which we take no action at all, would be much worse than the 2.4 C rise you mentioned.

At our present emissions rate, with no international efforts to control it, we would likely hit 2.0 C (3.6 F) above the preindustrial average by 2050, with even more warming locked in. By 2100, we could see around 5.0 C (9.0 F) above the preindustrial.

If that was to happen, we would see a number of changes this century. Sea levels will rise a foot by 2050 and 3 to 6 feet or more by 2100, rising as much as a foot or more each decade thereafter. The Arctic sea ice will likely melt away entirely in the summer by 2050. Most mountain glaciers and coral will disappear, and possibly the Amazon rainforest. Around 50% of species will be committed to extinction. Wildfires will increase 100% to 300% for every 1 C rise in the global average temperature.

Billions of dollars worth of Florida real estate could be underwater by 2050. By 2100, the value of drowned properties could exceed a half trillion. The biggest naval base in the world in Norfolk, Virginia will have to be relocated, and hundreds of other military installations will be impacted as well.

By 2045, there could be nuisance flooding every day of the year around the edges of Washington, D.C.; Annapolis, Maryland; and Wilmington, North Carolina, as well as for most of the year in Atlantic City, Miami, and Baltimore. The areas most susceptible to sea level rise will be northeastern North Carolina, the Mississippi Delta, and south Florida. Much infrastructure will likely be lost or damaged, including airports, cities, highways, military bases, nuclear waste storage sites, oil refineries, ports, power and waste treatment plants, railroads, and recreation areas.

By 2050, the ratio of record highs to record lows could shift to 20 to 1. By 2100, the ratio will likely be 50 to 1. By 2060, about half of the U.S. could be in extreme drought a great deal of the time. And once the soil is dry, baking leads to even higher temperatures. Dust bowl conditions could be the new normal in much of the western U.S. by 2095.

So business-as-usual emissions will likely exceed our abilities to adapt. The rate of change will become overwhelming beyond a point.

Again, those are some of the estimated worst-case scenarios for this century, based on business-a-usual projections. They are terrible, but they still don't come close to what you are suggesting. And leveling off at 2.4 C would entail considerable improvements over the worst-case scenarios, even though it would still be dire.

Plus commitments will be tightened further as we actually make progress.