Spain's ongoing battle to save the coral, but is time running out?

It's the worst bleaching event on record - 84 percent of the world's coral reefs have suffered mass bleaching over the last two years leading to a significant loss of coral life, according to International Coral Reef Initiative (ICRI).

The principal cause is climate change, heating oceans, with pollution and other human activity pushing coral reefs closer to a point of no return.

Time is running out for coral reefs. We could lose 90 percent of them by 2050, and by the end of the century the UN is warning these marine treasures could be just memories.

But there are some people fighting for their future in the south of Spain. Coral Soul is an NGO dedicated to the conservation and restoration of coral reefs.

Last year CGTN got in the water to see their project in La Herradura, Granada, in southern Spain, where candelabra corals are thriving once again.

We caught up with co-founders Zaida Parra and Marina Palacios to hear about current active projects in Granada and Sardinia in Italy, and a brand new one too.

Smiling and upbeat as ever, Zaida reveals she wasn't in the water because she's pregnant, yet and she remain unshakeably positive about the future.

But how so in the face of such concerning news?

"I think part of it is just a natural attitude, we are positive people, but also it’s because we see really positive results in the work we do. We put our all into this, body and soul, and we have hope in strategic points. Of course, we are very aware that there are zones that probably won't recover, but there are others where if you study them and identify resilient species then we can help them recover and then neighboring ecosystems can thrive, these 'Hope Spots' that we want to develop."

"In Granada for example we've seen significant improvements and now we're expanding the nurseries and recovery zones. When we dive we see certain species and corals that have greater resistance to change so we try to identify them so they reproduce and create a more resilient ecosystem."

At the University of Cadiz in southwestern Spain Coral Soul is part of a pioneering new study on gorgonias or soft corals to see how warming and heat stress affect them.

Leading this new project is Doctor María Laura Martin Diaz who is a full professor at the University of Cadiz and member of the University Marine Research Institute (INMAR).

"We have to start saying that the seas, the oceans, are very important for all of us," she said.

"All the climate, the weather, is controlled by the oceans. Almost 25 percent of life in the sea is developed and formed in coral reefs. They are ecosystems that preserve our ocean. If coral reefs are not healthy, that could mean that the ocean is not healthy either. So this project is completely new and we are really really enthusiastic.

"It's very challenging because we have to work with very special and vulnerable species, but if we could find responses or indicators of ocean warming or contamination effects in this species that could be very, very interesting and it could provide us information about what is going on and tools for protecting specific areas."

It's impossible to overstate just how important coral and coral reefs are to our planet.

Losing them would cause entire food chains to collapse, catastrophic for a billion people worldwide who rely on the sea for food and income.

Scientists are also checking reef animals for clues to treat cancer and brain diseases like Alzheimer's. If reefs disappear, we could lose cures we haven't even found yet.

So how does Doctor Martin Diaz feel about the prospect of saving them?

"I have hope. But I don't know if we have time," she said.