Short answers, pulled from the story.
Between 1901 and 2018, the global mean sea level rose by roughly 20 centimeters. The rate has accelerated over this period, reaching 4.62 millimeters per year for the decade 2013 to 2022, which is faster than at any point over at least the past 3,000 to 4,000 years.
Between 1993 and 2018, melting ice sheets and glaciers accounted for 44 percent of sea level rise, while thermal expansion of ocean water contributed another 42 percent. Climate change driven by human activities is the primary reason the rate of rise has been persistently accelerating.
Under the IPCC Sixth Assessment Report, projections for 2100 range widely by emissions scenario. A low-emissions pathway roughly in line with the Paris Agreement goals projects tens of centimeters of rise, while a high-emissions scenario could produce more than 1 meter, and ice cliff instability processes could push that figure to 1.6 meters or beyond.
Scientists estimate that 2050 levels of sea level rise would place roughly 150 million people below the high-tide line and expose about 300 million to annual flooding. As of the 20th of May 2025, approximately 230 million people live within 1 meter above current sea level, and 1 billion live within 10 meters.
Thwaites Glacier currently accounts for 4 percent of global sea level rise and, together with Pine Island Glacier, buttresses the entire West Antarctic Ice Sheet. If Thwaites were to collapse, the rest of the ice sheet would eventually follow, contributing roughly 3.3 meters to global sea levels, though this would take at least several centuries.
Low-lying coastal and island Indigenous communities face not only physical displacement but also the loss of land-based cultural practices, languages, and tribal systems tied to ancestral territories. The community of Isle de Jean Charles in Louisiana has already lost the majority of its land to sea level rise and coastal erosion, prompting a state-supported relocation effort.