“Even just a small difference in a reef’s height can make a big difference in risk, according to a study published last year in the journal Nature. Flood risk is often measured by what’s called the 100-year-flood zone — an area in which the chance of a flood in a given year is 1 percent. If coral reefs in the US lose 1 meter of height, that zone in the US would grow by 104 square kilometers (or about 26,000 acres), putting about 51,000 more people at risk of flooding, the study found.
That’s a big reason why losing reefs is so frightening. “These losses could escalate flood risk in just years to levels not anticipated by sea-level rise for decades or a century,” the authors of the Nature study wrote.”
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“Ultimately, protecting and restoring coral reefs is about much more than protecting coastal cities. Though they cover less than 1 percent of the world’s oceans, reefs sustain about one-quarter of all marine life and half of all federally managed fisheries. It’s hard to think of a better example of how helping an ecosystem is also helping ourselves.”
https://www.vox.com/down-to-earth/23046997/coral-reefs-climate-change-hurricanes