Steve Sailer points out that after the celebrated bet between Julian Simon and Paul Ehrlich in 1980-1990 (which Simon won by taking the optimistic view), there was a second bet Ehrlich proposed that Simon would not take.
Eyeballing the conditions of the second bet, though, one notes that few of them have directly negative results if they come true (which they largely did). The points Ehrlich was making were obvious, but, for example, warmer years on average in 2002-2004 versus 1992-1994 suggests that global warming is happening, certainly, but not that it is having a disastrous effect on humanity.
Similarly, if there are fewer acres of fewer land per capita, but food production is higher, this is not obviously a bad thing.
The one really unambiguously bad prediction that Ehrlich makes here is that in 2004, more people will die of AIDS than in 1994. And Ehrlich wins that one, but it doesn’t make him look wildly good in hindsight either: the spirit of the bet seems clearly to go in Simon’s favor. According to the World Health Organization, AIDS deaths peaked in 2005, and have been declining since; AIDS, which certainly still a blight, is no longer the bogeyman that it was in the 90’s.
Like predictors of the future in general, predictors of doom myopically exaggerate current trends. The future is weirder (though not necessarily kinder) than that.
 I note that I think that Steve Sailer advances routinely deeply racist arguments and is basically a bad person. He’s also obviously smart, and I don’t think that it does anyone much good to hide the existence of deeply racist people, or not link their blogs. So please understand that my link is not an endorsement. Not that this topic has much of anything to do with race.
 In fairness, it was a much braver position to state that global warming was definitely happening in the 90’s than it is today. But also in fairness, we see in retrospect that three-year global warmth figures are a bad proxy for global trends, as significant cycles take place that are longer than three-year trends.