As sea levels rise around the planet, ultimate coastal flooding events will become more common in nine-in-coastal areas in the United States, new research suggests. Although the sea-level rise is slow, it is accelerating as climate change increases. Under the worst-case scenario, it is estimated that millions of people will be displaced by the end of the century; Even a slight rise in sea level rise could inadvertently increase the frequency of coastal flooding, say researchers from the U.S. Geological Survey, the University of Illinois at Chicago and the University of Hawaii.
Write the study authors in Scientific Reports, “Rising sea levels will fundamentally redefine the 21st-century coastline. In many coastal areas, global sea-level rise estimates for 2100 are comparable to today’s extreme but short-lived increase in water levels due to storms.”
Records based on historical records, extreme flood events occur every “once in 50 years” about 50 years after their nickname is suggested. Coastal floods are affected by a variety of factors including tidal surges, storms, and climate cycles. The data was collected from more than 200 tidal gauges along the U.S. coast to determine the extent to which frequent flood events could occur based on sea-level rise. As sea levels rise, so does the risk of coastal flooding. By 2050, most coastal cities will see “dramatically higher” flood risk.
The authors write, “Combining this growth rate with established sea-level growth forecasts, we found that the risk of extreme flooding doubles every five years.” “This new approach, based on a calendar date, establishes a new flood risk system, urgently communicating for sea-level rise planning and adaptation.”
Coastal flooding rates are expected to double every five years, and in the next three decades, about three-quarters of the final tested sites in 50 years could turn into annual events. By the end of 2100, low-latitude areas are expected to become the most vulnerable to 90 percent of the high-altitude areas measured across the U.S. coast almost every day of one-time flooding. At sensitive sites in the Caribbean and Hawaii, for example, sea-level rise is expected to double with each centimeter of sea-level rise. However, each coast will experience different levels of flooding. In general, smaller levels of sea-level rise can be seen on the west coast while average growth on the east coast is almost double, especially in areas prone to tropical storms.
The authors write, “Under the influence of established emission trajectories and sea-level forecasts, the risk of extreme coastal flooding will double every 5 years in the foreseeable future in most places in the United States. As the frequency of floods increases, we expect acceleration related to various coastal risks such as beaches and cliffs.” “Our society has not yet fully understood the impending change of government and its consequences predicted in coastal hazards.”
