text: Finally the report argues that "global warming may increase the frequency of extreme weather events, including both prolonged periods with little precipitation and periods of heavy downpour and snowfall, leading both to more droughts and more inland floods." One scenario described by the report could have 100-year floods occurring every 3 to 11 years in New York City by 2100. Higher sea levels could also push salt water further up the Hudson River threatening the city's water supply.