🌊 Once-a-century floods soon every year?

Our planet now experiences extreme coastal floods with a much higher frequency than before. A recent study reveals that what constituted a once-in-a-century event in 1900 now occurs about every eight years. And it is expected to get even worse.

To distinguish human influence from natural forces, scientists use climate models. They compare these models to historical observations from tide gauges, which have existed for a century in over a hundred locations. By simulating experiments where greenhouse gases remain constant, they can isolate the impact of human activities.


The results show that anthropogenic influence has become dominant since the 1970s, increasing the frequency of century-scale events twelvefold globally.

Also, the current average rise of just a few centimeters has daily consequences for coastal communities. For example, in Norfolk, Virginia, high-tide flooding has become common, disrupting commutes and increasing insurance costs. The cumulative damage from these small events can equal that of a major hurricane.

And while a once-in-a-century event like Hurricane Sandy was once bearable once in a lifetime, having to endure it every eight years – the current frequency – is unthinkable.

Since humans are the dominant factor, reducing greenhouse gas emissions is a possible action, although the results will become increasingly delayed due to the time already lost. Sea level rise is now inevitable until 2060, regardless of effort. Adaptation remains necessary, but taking control now can prevent an even more dangerous rise afterward.

IPCC projections indicate that by 2050, between 19% and 31% of tide gauge sites will experience events that were once centennial every year. Tropical regions will be the most affected, as their climate is less variable.