Milan Radisics / Aerial shot of the Gemasolar Thermosolar Plant owned by Torresol Energy, it uses molten salt as its heat transfer fluid and energy storage medium to produce energy for up to 24 hours a day, Seville, S...

Milan Radisics / Aerial shot of the Gemasolar Thermosolar Plant owned by Torresol Energy, it uses molten salt as its heat transfer fluid and energy storage medium to produce energy for up to 24 hours a day, Seville,...

Shane P. White / Tephra during volcanic eruption, Mount Yasur, Tanna Island, Vanuatu

Tony Wu / Humpback whales (Megaptera novaeangliae) male during a competetive heat run. Vava'u, Tonga, South Pacific.

Tony Wu / Humpback whales (Megaptera novaeangliae) in a heat run, with six males competing for the attention of a female that already has a calf. Vava'u, Kingdom of Tonga

Tony Wu / Humpback whale (Megaptera novaeangliae) and her calf pursued by males during heat run. Vava'u, Tonga, Pacific Ocean.

Tony Wu / Humpback whale (Megaptera novaeangliae) female with calf, pursued by males during heat run. Vava'u, Kingdom of Tonga. Pacific Ocean.

Denis-Huot / Bush fire at dusk, Masai-Mara Game Reserve, Kenya, October 2012

Denis-Huot / African Elephant (Loxodonta africana) tusks being burnt after confiscation from poachers. Nairobi National Park, Kenya, 1990.

Paul D Stewart / Aerial view of Grand Prismatic thermal spring in Yellowstone National Park, USA. The bright colours are natural, coming from thermophile bacteria in the water. People can be seen walking on the raised...

Cheryl-Samantha Owen / Cape gannet (Morus capensis) drying in a heated pen (a heat lamp illuminates the pen with a red light) after its first wash, which removed some of the oil that coated its feathers. Some oil remains on...

Martin Dohrn / Wood ant (Formica rufa) basking to absorb heat from the sun which is brought back to the nest when they return, Europe