Onshore Thermokarst Primes Subsea Permafrost Degradation

The response of permafrost to marine submergence can vary between ice-rich late Pleistocene deposits and the thermokarst basins that thawed out during Holocene. We hypothesize inundated Alases offshore thaw faster than submerged Yedoma. To test this hypothesis, we estimated depths top ice-bearing Bykovsky Peninsula in northeastern Siberia using electrical resistivity surveys. surveys traversed lagoon deposits, drained refrozen Alas undisturbed Yedoma from coastline 373 m offshore. While degradation rates were range similar sites, up 170 faster. Remote sensing analyses suggest 54 lagoons wider 500 along northeast Siberian northwest American coasts originated basins. Given abundance lakes parts Arctic coastline, their effect on subsea must be similarly prevalent.