In a development that will help predict sea level rise, scientists have used an innovation in radar analysis to accurately image the vast subglacial water system under West Antarctica's Thwaites Glacier, detecting a swamp-like canal system several times as large as Florida's Everglades. The new observations suggest dynamics of the subglacial water system may be as important as ocean influences in predicting the fate of Thwaites, which holds substantial potential for triggering sea-level rise....