MOBILE, Ala. — As we wait for a massive storm that could dump seven inches of rain here to make it over from New Orleans, this is a good time to talk about the upcoming hurricane season of 2018 and the latest science news about global warming and climate change.
Climate scientists from Colorado State University have already released a prediction saying this year’s hurricane season, which officially begins June 1, could bring an above-average 14 named storms, 7 hurricanes and 3 major hurricanes.
While the Trump administration is still stifling any talk about global warming or climate change and bringing even more anti-science people into the federal agencies even as climate change denier Scott Pruitt may be on the way out at EPA, two new studies raise major alarms that the long-predicted slowing of the Gulf Stream is already in progress and could hasten sea level rise 100 years ahead of schedule.
One study published in the journal Nature, Observed fingerprint of a weakening Atlantic Ocean overturning circulation, was led by the Potsdam Institute for Climate Impact Research. It finds that the Atlantic Meridional Overturning Circulation system, another name for the Gulf Stream, has weakened “around 15 percent” since the mid-20th century, bringing it to “a new record low.”
The system circulates warmer water northward and cooler water south.
“I think we’re close to a tipping point,” climatologist Michael Mann told ThinkProgress in an email interview. The system slow down “is without precedent” in more than a millennium he said: “It’s happening about a century ahead of schedule relative to what the models predict.”
The impacts of such a slowdown include much faster sea level rise, he indicated, along with warmer sea surface temperatures, which feed hurricanes to make them stronger and more devastating when they make landfall.
Both of those effects are already being observed — and together they make devastating storm surges of the kind seen during Superstorm Sandy far more likely.
Another new study in the same issue of Nature “supports this finding and places it in a longer climate history context,” as Potsdam’s Stefan Rahmstorf notes at RealClimate, showing the Gulf Stream moving at its slowest pace in at least 1,600 years.
A video from Potsdam Institute explains how the slowdown is being driven by human-caused climate change: The observed fingerprint of temperature changes in the Atlantic are precisely what the models predicted would happen when the slowdown began in earnest.