Photojournalist Alexandre Meneghini knew the voyage to Antarctica might be a bumpy ride. But he refused to take motion sickness pills. "That was a mistake," he later admitted. At times, he felt like he was inside a centrifuge. Especially here, in the infamous Drake Passage — a body of water near Cape Horn where the Pacific and Atlantic oceans converge.

But Antarctica's stunning natural beauty makes the rough seas worth enduring. On this voyage organized by Greenpeace, whales surfaced near the research ship multiple times. More than a dozen species of whale spend at least part of the year in Antarctic waters, including the blue, Minke, humpback and sperm whale.

But Meneghini also saw more worrying activity on the horizon. This krill-fishing vessel was spotted in Crescent Bay. For a long time, krill was of little interest to humans. Now, they are being targeted by the fishing industry, which markets krill oil as a source of omega-3. That's a problem, according to Greenpeace, as almost all Antarctic animals in rely on krill as a staple food.

Meneghini's journey though the Antarctic featured some unforgettable moments, and encounters with penguins certainly ranked among them. Here, he came face-to-face with a colony of Gentoo penguins on Cuverville Island. Krill makes up the bulk of these birds' diet.

Gentoo penguins waddle across an ice-free spot in Neko Harbor. Meneghini said getting so close to penguins on shore made him feel like a kid in a sweet shop. "If you don't move, the penguins will stay close by for hours," the photographer said.

A fur seal takes a break from the water in Maxwell Bay. Fur seals were hunted to close to extinction by the early 20th century. Since then, their numbers have recovered. Still, individual animals are at risk of getting entangled in shipping debris. And although they also feed on fish and even penguins, fur seals could come under pressure from krill fishing, conservationists warn.

Of course, Antractica wildlife isn't only threatened by fishing. Climate change is eroding the continent's glaciers faster than expected. That's disrupting local species' habitat — and threatens to force global sea levels up to the point where some worst-case scenarios see all the world's coastal cities wiped out before the end of this century.

Joao Pereira de Araujo stands in front of his home in Rio Branco in Brazil after the river Acre rose to a record high of 18.4 meters in March 2015. Nearly 100,000 residents were affected by the extreme flood. Photographer Gideon Mendel portrays flood victims worldwide to draw attention to their fates. His works are part of the show "Extreme. Environments" at Frankfurt's photo triennial, RAY 2018.

With his project "Drowning World," Mendel has been exploring the personal impact of climate change within a global context since 2007. "In a flooded environment, life is suddenly turned upside down, normalcy no longer exists and people need to adapt," he said. Francisca dos Santos is captured here outside her flooded home in Rio Branco, Brazil, in 2015.

The South African-born, London-based photojournalist started his "Drowning World" project when he documented widescale flooding in Yorkshire in 2007. "At that time I had small children and two questions occupied me for their sake: In what kind of world do we live; and what will the world look like in the year 2050?" he asked at an exhibition of the series in Zingst, in northern Germany.

Mendel's images show how water is the great equalizer that makes everyone the same. This photo of a photo found in Shirley Armitage's home in Somerset, England was one of many destroyed by flooding in February 2014. Mendel created another photo series called "Water Marks" that looks at how floodwaters have transformed very personal family photographs.

A water-damaged photograph from the home of Abdul Rashid in Kashmir, India, also in 2014. "I am fascinated by the arbitrary but shocking effects that floods have on precious keepsakes," says the photographer.

This is Gideon Mendel's personal favorite: It shows the baker Florence Abraham from Nigeria, who had a bakery with 50 employees and lost everything in the flood of 2012. The show "Extreme. Environments" can be seen until September 9, 2018 in the Fotografie Forum Frankfurt.