evidence: Long-term changes in global mean sea level (GMSL) are predominantly driven by three processes: Thermal expansion of ocean water as it absorbs heat, the addition of fresh water to the ocean from the melting of glaciers and ice sheets, and land water storage. As the atmosphere warms, much of its heat gets absorbed by the ocean, causing the water to expand. More than 90% of warming over the past 50 years has occurred in the ocean. Along with this thermal expansion, land-based glaciers and ice sheets are melting. Since 2002, Greenland is losing about 277 gigatonnes (Gt) of ice per year, based on measurements acquired by the Gravity Recovery and Climate Experiment (GRACE) and GRACE Follow-On (GRACE-FO) missions, and Antarctica losing approximately 149 Gt/year. To put this into perspective, one Gt is equivalent to one billion metric tons, 2.2 trillion pounds, or 10,000 fully-loaded U.S. aircraft carriers. New York's Central Park is 4 kilometers long and 0.8 kilometers wide. A gigatonne of ice placed in this equivalent area would extend 341 meters (1,119 feet) high. [...] Locally and regionally, sea level change can be significantly different from the global average due to factors such as natural and human-induced subsidence (sinking or settling of the ground), ocean currents, and rebound from the compressive weight of Ice Age glaciers. [...] Our current scientific understanding of sea level change is unprecedented due to long-term sea level records and almost 30 years of satellite altimetry. Data available without restriction through NASA's Earth Observing System Data and Information System (EOSDIS) further support this understanding.