Rising Sea Levels

When the great ice sheets that covered large parts of Europe, Asia and North America started to melt some 20,000 years ago, sea levels were around 130 meters lower than they are today.

The melt off was gradual and relatively slow to start with. It took 6,000 years to raise the sea level 10 meters. The melt off was a mere 1.7 millimeters per year.

However, 14,000 years ago, things changed rapidly. Over the next 6,000 years, sea levels rose 120 meters to roughly where it is today. The melt off was during that period a full 20 millimeters per year, on average.

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With sea levels rising 1 meter every 50 years, flooding would have been common, and coastal settlements would have had to constantly adapt and move.

By comparison, sea levels from 1870 to 1990 rose by a mere 200 millimeters. At that rate, it would take 600 years for sea levels to rise 1 meter. However, measurements indicate that this rate has accelerated since 1990. We are currently seeing sea levels rise twice as fast. At this rate, it will take 300 years for sea levels to rise 1 meter.

Sea levels are in other words currently rising 6 to 12 times slower than what was the norm during the 6,000 years going from 14,000 to 8,000 years ago.