To the water, to where the liquid depths of sanctuary and sanity are.

It’s always been this way – the magnetic effect of water on the photographer and activist Gideon Mendel, 60. He’s yielded to the pull of what’s beneath the surface from his very first childhood swim, he says.

Then, in 2007, water became this other thing too for Mendel. It was a year the rains didn’t stop falling in the north of the United Kingdom, the country Mendel has called home since leaving South Africa in 1990. With the rains came the floods and the water rose and rose.

As the rain fell in the UK, Mendel headed out on assignment to India with NGO Action Aid which was responding to floods in parts of that country. He says: “The floods over those weeks struck me as something being shared despite different circumstances and different countries. There was universality in our shared vulnerability.”

So began his intentionally long, slow photography project. The nurtured incubation of work and patience in allowing time to pass for better conceptualisation and storytelling were lessons he learnt from the late South African master photographer David Goldblatt. His journey to document climate change would be through photographing floods and his cameras would be his tool and testament to make real the truth that no one gets out unscathed while the planet burns.

Mendel turned up at flood zones around the world over the next 11 years, from Pakistan to Brazil, from Haiti to Australia and from Thailand to Nigeria, the United States and France. What has emerged is a body of work titled Drowning World and is made up of narrative threads in Submerged Portraits, Floodlines and Watermark. His images exert power through unflinching confrontation also through an eerie stillness and quiet. It comes from Mendel’s practised precision and deliberate composition in ordering horror and beauty in these waterscapes where the natural order of things has been inverted.

There are portraits of people like Brazilian João Pereira de Araújo standing neck-deep in water in front of the door to his house in Rio Branco. His reflection is a haunted distortion, in his drowned world. In Texas there’s Torrey Mosvold, wearing waders to get through water that reaches almost to his knees. He is posed against an ornate mirror that reflects the sparkling light from an equally ornate candelabrum. It makes the waterline the unequivocal divide between what survives and what does not.

“I wanted these portraits to be a direct confrontation, a gaze back at the viewer, and I searched out a consistent gaze across cultures and countries because climate change is not happening to brown or black people somewhere far away; it’s happening to everyone,” he says.

Personal proximity to doom from the upward creep of the earth’s temperatures is as true in Mendel’s Watermark series. The series is made up of salvaged soggy photo albums, retrieved from the detritus of floods. To date, he’s collected about 1,200 photos.

Water on chemicals has eaten through memories in Watermarks. Milestones and happy moments once safely contained on photographic paper have been erased or altered irrevocably by the water.

It was in 2009 that Mendel found out that his own work could not be waterproofed. In Savanne Desolée, Haiti, while walking through mud and water, the leather strap on his Rolleiflex camera broke. It sent his old-style medium format box camera into the water. Later on the same trip his second Rolleiflex, while set up on a tripod, was accidentally upended, also sending that camera into the water.

“I had my SLR as a back-up but I didn’t have my spare charger, so I had to clean and dry the Rolleiflex cameras as best as I could and use it even as it got stiffer and stiffer as it started to rust,” he says.

Back in London, he was nervous about what he managed to capture with compromised gear. And when the prints were made it was the disaster he feared.

“I was very upset. Essentially the photos were ruined, but then I realised that the water was having a direct impact on the film, unmediated by the camera,” he says.

Again the themes of no escape for anyone and the urgent choice between collective peril and collective action in facing up to our climate catastrophe became patent and palpable. And so Watermarks came into being.

“I don’t want to be prescriptive about these works or about how people should react to climate change. I get asked that question a lot – ‘what can I do?’ – and I think that the individualised response to climate change is part of the problem.”

His work has a binding effect though, he’s seen it as people leave his exhibitions unsettled and stirred. Photos like those in Floodlines at first glance look like beautiful patterns and symmetry of life, then a deeper viewing shows them as surreal substitutions for once familiar landscapes and lives.

“My works are increasingly being used in protests and for activism and I find these kinds of collaborations and these new ways of protesting invigorating and inspiring,” he says.

His works have appeared in magazines and other publications. In the last year alone they’ve been in nine exhibitions in galleries, museums and at festivals. Now they are part of protest marches, held up like banners, declaring a message not in slogans but in pixels and in people made present through how he’s captured their realities.

These collaborations he feels can make a difference in halting climate change. It brings individuals together, not to feel abandoned in their personal morality to recycle, to eat less meat, drive less even as temperatures increase, targets are missed and treaties are ignored. Standing together means standing stronger against governments and corporates that Mendel says have got off the hook too easily.

Mendel has never shied away from taking a stand and earned distinction and renown in the mid-Eighties, working in South Africa. He started his career as a press photographer at The Star in Johannesburg. It was the decade marked by political violence and rage.

“Working in the fire of the uprisings of the Eighties marked me as photographer and an artist,” he says of not been able to look away long after he had put down his camera.

Activism, art and working a job have an intersecting point for Mendel, who is represented by ARTCO Gallery in South Africa. It would compel him to go on to document, sometimes in collaboration with the Treatment Action Campaign (TAC), the torment of HIV and Aids in the 1990s and early 2000s.

In South Africa, even as the death tolls rose and the government stuck to denial as a response, he humanised the stigmatised dying, he showed the innocence and resilience in the lives of orphans left behind by the virus and he captured the celebration of surviving and thriving of those living as HIV-positive people.

Mendel continues with all these projects. “I have a hard time letting go,” he says of how he works evolve with him, how he evolves with his work and even how campaigns and issues he champions evolve.

There’s no time to sit back and do nothing for this father of two young adults. He believes his children deserve a better planet to grow older on. He’s already working on a new body of work. It centres on objects and fire and is still framed in the story of the climate crisis. Capturing the melted, the charred and the smouldering everyday items is documentary and a warning of what could be the dreadful legacy of humankind in self-destruction mode.

“With Burning Memory I am positioning myself as a contemporary archaeologist, photographing the objects that someone may look at in the future to understand how we ended up destroying ourselves.

“Sometimes I do feel like it’s all messed up and we should have been taking on this climate crisis 30 or 40 years ago already. Then I veer back to knowing that every bit of action now matters,” he says.

Mendel is an activist; he will take another picture that matters. It’s like being underwater; he has to come up for breath. It’s urgent and involuntary; it’s also life or death.

Gideon Mendel is represented by ARTCO in South Africa