Sea level rise already delays coastal commuters

Although the most dire societal impacts of sea-level rise (SLR) typically manifest toward the end of the 21st century, many coastal communities face challenges in the present due to recurrent tidal flooding. Few studies have documented transportation disruptions due to tidal flooding in the recent past. Here, we address this issue by combining home and work locations for approximately 500 million commuters in coastal US counties from 2002 to 2017. We find tidal flooding delays coastal commuters by approximately 22 min per year in 2015–2017, increasing to between 200 and 650 min by 2060 under various SLR scenarios. Adjustments in residential and work locations reduce the growth in commuting delays for approximately 40% of US counties. For residents in coastal counties, SLR is not a distant threat—it is already lapping at their toes.