Extreme coastal flooding, which previously occurred only rarely, is becoming significantly more frequent due to sea level rise caused by human-induced climate change. This is stated in a new study published in the journal Nature Climate Change.

Scientists note that such floods occur when high tides and storm surges coincide with an already elevated sea level. These factors are intensified by global warming and natural climate variability.

According to the study’s findings, events that historically had about a 1% chance of occurring each year now happen roughly 12 times more often. At the same time, scientists estimate that human activity has increased their likelihood by about four times compared with natural conditions.

The authors analyzed data from more than 100 tide gauge stations around the world and also used climate modeling covering the period from 1900 to 2005. They clarify that after 2005 the number of comparable models was limited; however, the actual risk today is likely even higher, as the influence of human-driven factors continues to grow.

A separate study published in the journal Science Advances also confirms the rise in extreme ocean levels, indicating that about 58% of days with severe flooding during the 2000–2018 period are linked to climate change. In addition, the number of days exceeding critical water levels has nearly tripled since the 1970s.

According to the researchers, today “virtually every coastal flood bears traces of human influence through climate change.” Scientists emphasize that without the additional sea level rise caused by global warming, many of these events would not have reached the level of catastrophic flooding.

The study’s authors warn that the threat continues to grow, and coastal regions need to strengthen adaptation measures and infrastructure protection.