New York, America's financial capital and most populous city, could be hit every five years by the kind of floods that once occurred every 500 years, a new study predicts.

The report was published in the Proceedings of the National Academy of Sciences ahead of the fifth anniversary of Superstorm Sandy, which paralyzed New York in October 2012 and killed more than 150 people across the eastern seaboard.

Sandy clocked up damages worth $42 billion just for New York state alone.

The study warned that the likelihood of floods of 7.4 feet (2.3 meters) that happened once every 500 years pre-industrialization before 1800, and once every 25 years between 1970 to 2005, could occur every five years by 2030-2045.

The study's projections are based on rising sea levels and potential partial collapse of the Antarctic ice sheet.

While scientists generally agree that sea levels will continue to rise, there is uncertainty over how much.

The study predicted they would likely rise about five to 11 inches (13 to 28 cm) in New York between 2000 and 2030.

Over the longer term, sea-level rise in New York could exceed eight feet by the end of the century if the West Antarctic Ice Sheet rapidly melts.

But the studys presumed that greenhouse gas emissions will rise until the end of the century -- considered a "worst case" scenario many scientists question.

The overall flood heights associated with tropical cyclones in New York would "to increase greatly," in coming centuries compared with preindustrial or modern flood heights, the study warned.

Researchers from Rutgers University, Pennsylvania State University, Princeton, the Massachusetts Institute of Technology, the University of Massachusetts Amherst and Woods Hole Oceanographic Institution took part.

Source: AFP