22 Mar 2016
The rewards of being right about climate change are bittersweet. James Hansen should know this better than most — he warned of this whole thing before Congress in 1988, when he was director of NASA’s Institute for Space Studies. At the time, the world was experiencing its warmest five-month run since we started recording temperatures 130 years earlier. Hansen said, “It is time to stop waffling so much and say that the evidence is pretty strong that the greenhouse effect is here.”
Fast forward 28 years and, while we’re hardly out of the Waffle House yet, we know much more about climate change science. Hansen is still worried that the rest of us aren’t worried enough.
Last summer, prior to countries’ United Nations negotiations in Paris, Hansen and 16 collaborators authored a draft paper that suggested we could see at least 10 feet of sea-level rise in as few as 50 years. If that sounds alarming to you, it is — 10 feet of sea-level rise is more than enough to effectively kick us out of even the most well-endowed coastal cities. Stitching together archaeological evidence of past climate change, current observations, and future-telling climate models, the authors suggested that even a small amount of global warming can rack up enormous consequences — and quickly.
However the paper, publicized before it had been through peer review, elicited a mix of shock and skepticism, with some journalists calling the news a “bombshell” but a number of scientists urging deeper consideration.
Now, the final version of the paper has been published in the journal Atmospheric Chemistry and Physics. It’s been reviewed and lightly edited, but its conclusions are still shocking — and still contentious.
So what’s the deal? The authors highlight several of threats they believe we’ll face this century, including many feet of sea-level rise, a halting of major ocean circulatory currents, and an outbreak of super storms. These are the big threats we’ve been afraid of — and Hansen et al. say they could be here before we know it — well before the Intergovernmental Panel on Climate Change’s sanctioned climate models predict.