Camp’s team now hope to expand a project that involves transplanting ‘super-survivor’ cuttings to at-risk areas. She has already set up a ‘multispecies coral nursery’ off Australia (imagine a mesh fence with cuttings of different types of coral fixed to it, weighed down close to the sea floor), but requires further funding and support. And it may not work: after all, the Great Barrier Reef – one of the seven wonders of the natural world, visible from outer space, and worth about £3 billion in tourism each year – is about the same size as Italy, and subject to all manner of different stresses. But it might.

‘There’s a real art to getting the message across. We fundamentally have to lower carbon emissions to save coral reefs, that’s number one, but we also need to look at alternative strategies we can use in addition to that,’ Camp says.

She is intensely aware that her messaging needs to be drenched in caution, lest people hear of her discovery and declare the problem solved – or worse, lest climate sceptics hoist it as an example of us underestimating the planet’s ability to survive, whatever the conditions.

‘Some people look for any excuse to do less, so we need to be honest but not give a false sense of security. Think of it like a toolbox. The main tool we have is lowering emissions, but that’s not working well enough alone, so what else do we have?’

Camp has been fascinated by coral reefs since childhood. The daughter of local-government workers, she grew up in Essex with two brothers (both are still there; one has his own business, the other’s a policeman). When she was seven, her father took her snorkelling during a holiday to the Bahamas. It was all she needed.

‘I vividly remember putting the mask on and for the first time seeing this whole life you couldn’t see from above the water, this complex coral network. At the time I just appreciated its beauty, but as I got older I started to understand how important that ecosystem is. That so many people and animals rely on it. A third of all fish stocks interact with the reef. They need it.’

As a teenager, she spent most summers in Spain, where she earnt her diving qualifications. By the time she was an adult she was a divemaster, but balanced that passion with one for basketball (she went on to play for Great Britain).

On a basketball scholarship, she completed an environmental science and chemistry degree at Belmont Abbey College in North Carolina, before a master’s in environmental management and business at Sheffield Hallam University, then a PhD in marine biology at the University of Essex – most of which was spent in the field, studying reefs around the world.

Today she is based at the University of Technology in Sydney, where she is one of the leading researchers focusing on climate change and coral reefs. Camp – whose vowels occasionally slip into a New South Wales twang, especially when talking about her life in Australia – lives in Sydney with her husband, Rawiri, a banker from New Zealand. They married in January, and she is teaching him to snorkel.

Seeing his appreciation of the underwater world has ‘reinvigorated’ her love for it, she says. Camp now reckons she’s completed ‘over 1,500 dives, most of them about an hour at least – I stopped counting’. By my calculations, she’s spent two months of her life underwater.

‘Probably about a quarter of my day job is in the field. The rest is in the labs, testing samples, or writing it up. But more and more important is the science communication, making sure people understand why we’re doing what we’re doing.’

It’s why accolades like making the Rolex shortlist are so valuable, as they allow her both to gain extra funding and to promote her work before people she might not normally reach.

‘For me, it’s about raising awareness of what’s going on in our oceans, so it’s more about exposure than the money. These are global issues and a brand like Rolex can facilitate that message.’

Last year she was also announced as one of 17 ‘young leaders’ for the Sustainable Development Goals by the United Nations. It’s a two-year position, and has seen her address the UN General Assembly once already. Do they listen?

‘Yeah, I’ve been pleasantly surprised. There’s an eagerness to have intergenerational discussions. We are the next custodians who will inherit the planet and give it to our children, and there’s a real commitment to make sure young people’s voices are heard.’

Britain seems to have embraced the anti-plastics message Sir David Attenborough and others have pushed into the mainstream. Australia is similarly filled with activists, Camp says, but the Queensland government hasn’t helped by recently approving the construction of an Adani coal mine – to be one of the largest in the world – in the Galilee Basin, near the Great Barrier Reef. Are we putting too much energy into banning straws?

‘The analogy I like to use is that if somebody has a terminal illness and breaks their leg, you obviously deal with the broken leg, but you don’t stop treating the illness. You can deal with short-term issues without losing sight of the bigger picture.’

By the end of the Explorers Festival in Washington, it’s been announced that Camp has narrowly missed out on becoming one of the five Rolex laureates. Those lucky few are João Campos-Silva, a Brazilian fishing ecologist who has devised a plan to save the world’s largest scaled freshwater fish, the arapaima; Grégoire Courtine, a French medical scientist with a method of allowing people with broken backs to walk again; Brian Gitta, a Ugandan IT specialist who has developed a new weapon in the war on malaria; Indian conservationist Krithi Karanth, who works to ease conflicts between people and wildlife; and the Canadian entrepreneur Miranda Wang, with her plan for plastics.