Transcript for American scientist works to save coral reefs
about it. The regs cue mission on the ocean floor. Matt Gutman with the American scientists in a race against time. Water of this tiny hawaiian island, Dr Ruth Gates is growing hope. She takes us to her undewater lab. Those cargo nets hold so-called supercoal, cull vated to withstand global warming. We are assisting evolution but doing what nature does naturally and doing it much more rapidly. Reporter: Coral are tiny animals. Their exoskeletons create reefs upon which 25% of the world's fish depend. At the great barrier reef in Australia. Which noaa scientist Scott heron showed us. Around 80 to 90% of this reef is impacted. Reporter: Nearly 50% of the reef has died just over the past 18 months. Back in Hawaii -- Can this bereplicated on the Dale big enough to save the world's coral? It will take a lot of people in many places with the same time with the same mission in mind. Reporter: If we fail to slow global warming, she adds, a bigger worry than coral survival will be human survival. Matt Gutman, ABC news, los Angeles. We hope you'll journey with Matt and those American scientists later tonight on "Nightline." Until then, I'm David Muir and I hope to see you tomorrow.
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