In particular, he frets about four tipping points: the collapse of the large ice sheets of Greenland and West Antarctica; large-scale changes in ocean circulation (possibly reversing the Gulf Stream); situations when warmth prompts more warmth (say, by the thawing of frozen methane); and the possibility of a warming trigger that may double the Earth’s temperature increase, to 6 degrees Celsius. (Even three degrees is now considered an unthinkable extreme.)
The “casino” aspect of his book’s title refers to the difficult debate over how much we should spend to protect the planet from these low-probability but potentially catastrophic events. Unfortunately, as Nordhaus acknowledges, dealing with global warming is but one of many worthy causes competing for tax dollars.
His views put him to the right of center on the ideological spectrum, but he has no patience with the few “contrarian” scientists and numerous political figures who contest the established science that global warming is real and ominous. Although he includes a hopeful chapter meant to appeal to thinking conservatives, not even DICE is smart enough to devise a solution to the intractable politics of climate change, which are stubbornly deadlocked.
The temptations of “free riding” — letting other industries or other nations do the heavy lifting, and letting tomorrow’s generations take care of themselves — seem almost overwhelming. It is a trillion-dollar problem and it requires a trillion-dollar solution, or so he concludes.