Overview

• A study in Geophysical Research Letters quantifies a one-meter shift in Earth’s North Pole and a 21 mm drop in global sea levels driven by dam impoundment through 2011.
• Since 1835, nearly 7,000 dams have stored enough water to fill the Grand Canyon twice, redistributing trillions of gallons and altering the planet’s mass distribution.
• Pole movement followed two regional phases as dams in North America and Europe from 1835 to 1954 nudged the axis toward Russia and China and dams in Asia and East Africa from 1954 to 2011 steered it back toward North America and the South Pacific.
• The phenomenon of true polar wander occurs when Earth’s rigid outer shell realigns over its molten interior in response to surface mass changes.
• Researchers say including reservoir storage in sea level rise projections is essential for accurate climate and planetary dynamics forecasts.