Earth's Water Loss: Drying Reservoirs Impact Sea Levels and Rotation

A recent study highlights a concerning trend: Earth's surface water reservoirs are drying up, impacting sea levels and the planet's rotation. Scientists have found a significant decline in Earth's water storage since 2000, combining satellite data, sea-level measurements, and polar motion observations. Between 2000 and 2002, soil moisture decreased by approximately 1,614 gigatonnes, exceeding Greenland's ice loss during a similar period. From 2003 to 2016, an additional 1,009 gigatonnes were lost. This depletion correlates with a global mean sea-level rise of approximately 4.4 mm and a shift in Earth's poles by approximately 45 centimeters. The decline is primarily driven by shifts in precipitation patterns and increased evaporative demand due to rising temperatures. The redistribution of water mass is also slowing the planet's rotation and causing a shift in the rotational pole. Researchers estimate the rotation axis has moved 45 cm due to changes in water location. This study underscores human-induced alterations to the water cycle, impacting sea levels and Earth's rotation, a cycle relatively stable since the last Ice Age. The current rate of water loss from land exceeds its replenishment, potentially becoming irreversible if global temperatures continue to rise.