A quarter of the world’s corals are now dead, victims of warming waters, changing ocean chemistry, sediment runoff, and disease. Many spectacular, heavily-touristed reefs have simply been loved to death.

But there are reasons for hope. Scientists around the world working on the front lines of the coral crisis have been inventing creative solutions that might buy the world’s reefs a little time.

Crawford Drury and his colleagues at the Hawaii Institute of Marine Biology are working to engineer more resilient corals, using a coral library for selective breeding experiments, and subjecting corals to different water conditions to see how they’ll adapt.

Some resilient corals are still in the wild, waiting to be found. Narrissa Spiers of the Kewalo Marine Laboratory in Honolulu found one such specimen hiding out in the polluted Honolulu Harbor.

Other scientists, like Danielle Dixson of the University of Delaware, are experimenting with corals that aren’t alive at all—3D-printed corals. The idea, she says, is to provide a sort of temporary housing for reef-dwellers after a big storm or human damage. Dixson likens these 3D-printed structures to the FEMA trailers brought in after a hurricane.

Dixson’s team is experimenting with these artificial corals in Fiji, to determine which animals use them as housing, and whether they spur the growth of new live corals too.

Two huge challenges remain. For any of these technologies to work at scale, we need quicker, more efficient ways to plant corals in the wild, says Tom Moore, the coral reef restoration lead at the National Oceanic and Atmospheric Administration. Listen to this chapter of the series, Degrees of Change.

Plus, California Governor Gavin Newsom imposed a moratorium on new fracking permits in the state. An independent scientific board will now need to review each project before it is approved. Reporter Rebecca Leber talks about what this state initiative tells us about the national debate on fracking. And, a look at the new members of the bipartisan Congressional Climate Solutions Caucus and their strategy for addressing climate change.

Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.

Edutainment and Activism with Angelica Ross