A study by University of Hawaii researchers and other scientists predicts that many low-lying atolls in the Pacific will be uninhabitable by midcentury due to a combination of wave-driven flooding and sea level rise.

The study, published last week in ScienceAdvances, improved estimates of atoll habitability by considering not only sea level rise, but also the effects of wave activity on islands and atolls less than 2 meters (about 6-1/2 feet) in elevation, according to a UH news release.

Previous studies considered only the hazard from average sea level rise gradually inundating the atolls, projecting habitability until 2100 or later.

The newly released study, which focused on Kwajalein Atoll’s Roi-Namur island in the Marshall Islands, included the additional effects of waves, which begin to have serious consequences far sooner. These include active flooding from breaches of coastal berms, damage to coastal infrastructure and contamination of freshwater aquifers, the release said.

U.S. Geological Survey geologist and lead author Curt Storlazzi predicted potable groundwater on the majority of atoll islands would be contaminated by 2030 to 2060, and stressed the urgency of evaluating which islands are most vulnerable and the need to begin exploring possible political and engineering solutions.

Agencies participating in the study included the USGS, National Oceanic and Atmospheric Administration and UH’s International Pacific Research Center, whose Hariharasubramanian Annamalai and Matthew Widlansky contributed by evaluating global climate models that best simulated recent conditions and trends, such as precipitation and sea surface temperatures, in the Pacific and Indian ocean regions.