ABSTRACT
Twenty thousand years ago, during the Last Glacial Maximum when the global average surface temperature was roughly 4–5°C (about 7–9°F) colder than at present, sea level was about 130 m (nearly 400 ft) below its current level due to the glacial build-up. This ice, which was piled 2 km (over a mile) deep over much of northern North America and Europe, melted away over 6000–10,000 years, so roughly at a rate of 1–2 m (about 3–6 ft) per century.
