Diving below the waves can be like entering another world, but for Hong Kong-based National Geographic Explorer Jonathan, it is also like travelling back in time. Jonathan discovered the stories of how underwater ecosystems (生态) have changed through time, and what can be done to stop their decline (数量骤减).

“I look at coral reefs (珊瑚礁),” says Jonathan. “What were they like in the past? How have they changed? And what has caused that change? How can we look at that ecosystem today and use my data to better protect it for the future?”

As Jonathan explains, Hong Kong’s coral has declined in the past few decades due to factors such as pollution and human activities. Without greater protection measures, some coral species   (物种) could disappear from Hong Kong waters forever.

“Hong Kong gives us amazing underwater biodiversity (生物多样性),” says Shea — another National Geographic Explorer, “However, populations of many species have been killed in large numbers by decades of overfishing and other human activities.”

Faced with such great challenges, Jonathan and Shea insist that swift action is needed to protect Hong Kong’s ocean ecosystem, and that better education is a key. “The first step is to understand what we have,” says Jonathan. “Because once you understand, you’ll start to care. And once you care, you’ll start to protect it.”

Shea adds that, “Through becoming educated, each person can begin to see why it’s important to protect our ocean environment, and rebuild that sense of connection between our oceans and our culture, history, and identity. We need to make effort every day into putting ocean protection in the first place. It’s a long way to go.”

The world will to have to start thinking seriously to save its coral reefs. Corals are comeback creatures. As the sea levels rose and fell over 30,000 years, Australia’s Great Barrier Reef, roughly the size of Italy, died and revived five times. But now, thanks to human activity, corals face the most complex conditions they have yet had to deal with.

According to the Intergovernmental Panel on Climate Change, a rise in global temperature of 1.5℃ above pre-industrial level could cause coral reefs to decline by 70-90%. The planet is about 1℃ hotter than in the 19th century and its seas are becoming warmer, stormier and more acidic. This is already affecting relations between corals and the single-celled algae (海藻) with which they live together, and which give them their colour. When waters become unusually warm, corals push the algae out, leaving reefs a ghostly white, which is happening five times as often as it did in the 1970s. Meanwhile the changing chemistry of the oceans lowers the abundance of carbonate ions (碳酸盐离子), making it harder for corals to form their skeletons (骨骼).

If corals go, divers and ocean biologists are not the only people who will miss them. Reefs take up only one percent of the sea floor, but support a quarter of the planet’s fish diversity. The fish that reefs shelter are especially valuable to their poorest human neighbours, many of whom depend on them as a source of protein. In the Coral Triangle, an area of water stretching across South-East Asia and into the Pacific which is home to three-quarters of known coral species, more than 130 million people rely on reefs for food and for their livelihoods in fishing and tourism.

Flat Holm, a small island in Britain's Bristol Channel, has no permanent residents and minimal infrastructure（设施）. The pretty land mass is now, however, becoming increasingly popular with tourists wishing to explore the rural landscape and view the island’s seabird colonies.

Though this is welcome news, meeting the island's growing energy needs without ruining its environment poses a challenge. Flat Holm team leader Natalie Taylor says, “As we promote the island more and we get more visitors here, there’s going to be a lot more demand for electricity so it’s really important that we’ve got a really high functioning system that can provide for those people. From an environmental point of view, we want to reduce the use of diesel（柴油）generators so that we can have as small ecological footprints as possible.”

While the Cardiff Council, which oversees the island, considered traditional solar and hydroelectricity, it was reluctant to carry out either, due to their high cost and permanent nature. According to energy and sustainability manager Gareth Harcombe, the officials were seeking a portable option that could be moved if the site was needed for another purpose.

Fortunately, the UK-based company Renovagen had the perfect solution. A small panel can provide 11kW of power within two minutes. A more extensive version, unrolled from a shipping container, can yield 300kW of electricity in less than an hour.

The solar panel “carpets”, laid on the island in early October, are being used to provide electricity to its sole pub and lighthouse. The Cardiff Council also plans to use them to charge two Nissan e-NV200 electric vehicles in the future.

In addition to providing power to remote islands like Flat Holm, Hingley hopes the Rapid Roll technology will be useful in areas affected by natural disasters. A good example is Puerto Rico, where most residents have been without electricity since Hurricane Maria destroyed the power lines in late September.