“As records get longer, questions come up,” says Gavin Schmidt, a climate scientist who heads NASA’s Goddard Institute for Space Studies in New York City. But the recent spate of studies suggests that scientists have homed in on an answer, he says. “It’s all coming together.”
If sea-level rise continues to accelerate at the current rate, Nerem says, the world’s oceans could rise by about 75 centimetres over the next century. That is in line with projections made by the Intergovernmental Panel on Climate Change in 2013.
“All of this gives us much more confidence that we understand what is happening,” Church says, and the message to policymakers is clear enough. Humanity needs to reduce its output of greenhouse-gas emissions, he says — and quickly. ”The decisions we make now will have impacts for hundreds, and perhaps thousands, of years.”