Mayor Bloomberg’s post-Sandy climate resilience plan just got another boon: Last Thursday, researchers at the University of Pennsylvania showed the sea-level rise was a factor in flooding during Sandy. Over the last two centuries, sea-level rise has contributed more and more to flooding in the city during major storm events.
Authors Andrew Kemp and Benjamin Horton looked at seven major hurricanes in New York’s history, starting all the way back in 1788 and ending with Sandy in 2012.
The study, published in the Journal of Quaternary Science, found that had Sandy made landfall in the 18th century, flooding would have been 22 inches lower than it was.
The change in sea level comes from a combination of water levels rising and more of the city’s shoreline land subsiding into the sea. On top of a raised baseline, it will become more and more likely that storm surges and high tides will cause flooding in low-lying parts of the city.
Though Kemp and Horton concede sea-level rise is still a relatively minor factor in flood levels compared to tides and storm surges, over the last 200 years sea-level changes have contributed more and more to the rising water during storms, and will only continue to exaggerate storm effects.
So batten down the hatches, folks, it’s all downhill from here.