Ocean circulation changes due to accelerated global warming had disastrous impacts on marine life. The coral reefs died, completely upsetting the balance of the marine ecosystem. Thousands of species were lost. In addition, continually rising temperatures caused the oceans to become less dense. The surface waters were separated from the nutrient-filled cold layer below. The remaining aquatic life deeper retreated deeper into the oceans and left scarcely any life near the surface. For mankind, the oceans became increasingly vast and lifeless expanses, littered with the ruins of the coastal cities which they continued to swallow.
Following the sudden rise of ocean levels after the glacial break in 2022, the waters still accessible to mankind were considered virtually lifeless. The lack of fishable seafood combined with more frequent and powerful storms rendered the oceans so dangerous to cross that traversing them was considered suicide. Even the most well equipped of travelers would do best to reconsider crossing the huge, dangerous expanses of watery wasteland that become known as the marine desert.