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Planet Health Report: SEA LEVEL

SEA LEVEL:
What if it keeps rising this fast?

The global average sea level has risen over 7 inches in the past 100 years. A few inches may not seem like much, but every inch of sea level rise covers 50-100 inches of beach. If the ice keeps melting, global sea level could rise more than 20 feet. That would put a lot of coastlines under water. Whole islands could disappear!

Map of southeastern U.S. shows areas in red that would be under water if sea level rose 6 meters or 20 feet. Much of the coastline, and all of southern Florida are colored red.

If the glacial ice covering Greenland were to melt, sea level would rise 20 feet (6 meters)! Credit: Center for Remote Sensing of Ice Sheets.

As global temperature goes up, ice trapped on land begins to melt, and sea level rises.

But something else also causes sea level to rise. Water expands as it gets warmer. As the temperature of the ocean goes up, the ocean actually expands, even without adding any water from the melting ice!

Sea level is another important measure of how fast our planet is changing.

Learn about how NASA satellites are keeping an eye on sea level rise!