In the study published on Monday in journal Proceedings of the National Academy of Sciences, researchers found that flood level height rose to about 4 feet between the years 850 and 2005.
According to the study, storms that would have happened every 500 years are now happening every 25 years.
Andra Reed, the lead author of this study said that sea level rise increases flood height and there is the fact that tropical cyclone characteristics are also getting impacted by climate change.
The flooding caused by Sandy was the result of several factors: rising ocean levels, high tide and especially the storm’s overall size, the researchers said. They could then work out the size of storm surges the cyclones would produce, and combine the information with sea level data to give flood heights across the whole 1,200-year period. They said that this has been due to both considerable rise in sea level and changes in the nature of storms.
Computer models suggest climate change could trigger Sandy-like flooding events in the future.
This was a first-of-its-kind study. We’ve had a hodgepodge of responses to Sandy and are still struggling with basic issues such as home buyouts, moving people away from the coast, and rebuilding with new expectations. With climate change, that becomes roughly a one-in-a-century event.
Joaquin’s trajectory is still uncertain – it could yet cut a path out to sea – but New York’s financiers are aiming to keep trading should it strike early next week.
To see if either had changed, Reed and her colleagues compared coastal flooding in New York City during two time periods: a “pre-anthropogenic era” when the human influence on climate was “minimal” (the years 850 to 1800) and an “anthropogenic era” when it was “dominant” (years 1970 to 2005). The most recent report provided climate projections through 2100 and laid out the increasing public health risks from extreme heat and coastal storms.
The researchers reduced their study to three geographical regions that show higher risk: Cairns in northeast Australia, Dubai in the United Arab Emirates, and the already mentioned Tampa Bay at Florida. During the height of hurricane Sandy on October 2012, New York City’s subways and traffic tunnels were heavily flooded, along with the destruction of the coastal wall in Manhattan area.
The main reason for higher storm surges is raised sea level.
“This research is telling us that we need to have risk management strategies in place and we need to start trying to do something to mitigate the climate change”, Reed said.
“Think of it like a snowplough”, says Andrea Hawkes of the University of North Carolina Wilmington, who was not involved in the study.