What triggered the jumps? As Broecker guessed in the late â80s and (after 30-some years of debate) many scientists now agree: abrupt, dramatic changes in the Atlantic Meridional Overturning Circulation.
That the climate could change violently had huge implications. As more carbon was being released into the atmosphere, Broecker and other scientists were getting increasingly anxious that it wasnât degrading the planet in only the steady, humdrum, âup goes the heatâ kind of way. They worried that humans were pushing the climate toward a big jump. âOur climate system has proven it can do very strange things,â he wrote in 1997. âWeâre entering dangerous territory and provoking an ornery beast.â What remained was a very important question: Could a leap be predicted?
In the 1990s, Ditlevsen found plain old climate change kind of dull, but…
