Crean Glacier was the second glacier Sir Ernest Shackleton faced as he traversed South Georgia Island about 100 years ago. When Tim Jarvis returned to the glacier two and half years ago, he found it heavily denuded of snow.

Carstensz Pyramid in Indonesia has had glaciers for at least the last 30,000 years, yet according to Tim Jarvis they have under two years left before they melt away. 

Tim Jarvis climbed Carstensz Pyramid in Papua, Indonesia, the highest mountain on the oceanic continent. It was the first stop on his three-peak series to raise awareness about climate change during the COP21 Paris climate change talks. 

Carstensz Pyramid is one of the world’s seven summits, and is considered to be very technically challenging. With notoriously bad weather and an 800m day of difficult mountaineering, Tim Jarvis is expects it to be the most challenging of the three peaks he’d tackle for his 25zero project. 

At 6268m, Chimborazo is Ecuador’s highest mountain, as well as a dormant volcano. Despite being only one degree south of the equator, the mountain is covered in glaciers, which provide water for Ecuadorans but are melting at an alarming rate. 

Glacier calving, or ice calving, shown here at Neko Harbour on the Antarctic Peninsula, is the sudden breaking away of a mass of ice from a glacier. The average annual air temperature of the Antarctic Peninsula has increased by about 3°C over the past 50 years. 

Mount Stanley is Africa’s third highest peak. Experts predict Stanley’s glaciers will be gone by 2030 due to climate change.

When Australian adventurer Tim Jarvis crossed Konig Glacier on South Georgia Island almost 100 years after Sir Ernest Shackleton did the same, he found it had retreated many kilometres up the valley. 

One of Ecuador’s most active volcanoes, Cotopaxi was one of the 25 mountains Tim Jarvis and the 25zero team summitted to raise awareness about glacier melt and climate change. 

Cotopaxi has lost about 40% of its glacial cap since 1976, and the trend is expected to continue. Its meltwaters provide fresh water and hydroelectric power to Ecuador’s capital, Quito. In 2015, NASA captured satellite images of the Cotopaxi Glacier showing the rate of glacial melt had increased.