That doesn't pass the sniff test. 50 Hiroshima-sized airbusts cause massive climate change, yet 528 above-ground nuclear tests, some with 1000 times the yield of the Hiroshima bomb, and many being ground bursts, had no observable effect?
Nuclear tests conducted in a desert or on an isolated island aren't going to start massive, out-of-control wildfires the way nuclear explosions in a city, grassland, forest or jungle will.
Guess where most of those nuclear tests were conducted?
For the US: The Pacific Proving Grounds, isolated locations in the Marshall Islands. Or the deserts of the American Southwest (both the Nevada test site and Nellis AFB. The tests in Amchitka, Alaska were all after the Partial Test Ban Treaty proscribed above-ground detonations in nuclear testing; hence they were condu...
A reminder for everyone: on this day in 1983, Stanislav Petrov saved the world.
It occurs to me this time around that there's an interesting relationship here - 9/26 is forgotten, while 9/11 is remembered. Do something charitable, and not patriotic, sometime today.