Jack Dykinga / Scalding hot water continuously spouting behind layers of mineral deposits, Fly Geyser, Black Rock Desert, Great Basin Desert, Nevada, USA

Jeff Vanuga / Aerial view of Grand Prismatic Springs Midway Geyser Basin. Yellowstone National Park, Wyoming, July 2011.

Floris van Breugel / A skier glides past an erupting geyser in the Old Faithful geyser basin in Yellowstone National Park. The cold temperatures in the winter cause the geysers to release more steam than usual making the...

Christophe Courteau / Steaming vents of Namafjall, near Myvatn, Iceland

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...

Erlend Haarberg / Fumaroles at Hverir at night with northern lights in sky above, Namafjall, Iceland, February 2011

Erlend Haarberg / Volcanic eruption at Eyjafjallajokull with ash and lava exploding into the air at night, Iceland, May 2010

Erlend Haarberg / Volcanic eruption at Eyjafjallajokull with lightning in the ash plume, Iceland, April 2010

Erlend Haarberg / Grasses moving in wind in front of acidic steam and solidified lava surface at Leirhnjukur, Iceland 2008

Jack Dykinga / Scalding hot water continuously spouting behind layers of mineral deposits, Fly Geyser, Black Rock Desert, Great Basin Desert, Nevada, USA

Erlend Haarberg / Steam vents at night with northern lights, Hverir, Namafjall, Iceland, February 2011

Erlend Haarberg / Steam vents at night, Hverirt, Namafjall, Iceland, February 2011

Orsolya Haarberg / Steam vents with northern lights at night, Hverir, Namafjall, Iceland, February 2011

Orsolya Haarberg / Colourful rhyolite mountain landscape, Landmannalaugar, Sveinsgil, Fjallabak Nature Reserve, Iceland, August 2010

Erlend Haarberg / Blahver hot spring and Eyvindarhver fumarole, Hveravellir, Iceland, May 2010

Hanne & Jens Eriksen / Fumarole in the Krafla volcano area, Iceland, June 2009

Peter Cairns / Castle Geyser erupting at dawn, Old Faithful geothermal area, Yelowstone National Park, Wyoming, USA, September 2008

Peter Cairns / Parched trees in front of Grand Prismatic Spring geothermal area, Yelowstone National Park, Wyoming, USA, September 2008

Loic Poidevin / Mineral deposits at the Dallol hydrothermal site, Salt lake Karoum, Danakil depression, Ethiopia, February 2009

Orsolya Haarberg / Ash plume, white cloud and snowy ridge at the subglacial volcanic eruption under the Eyjafjallajokull ice cap in Iceland, April 2010. Second place in Landscape category of the GDT 2011 competition

Jeff Vanuga / Thermal hot spring at Mud Volcano, Hayden Valley, Yellowstone National Park, Wyoming, USA.

Rob Tilley / River of lava flowing from the Pacaya volcano, Los Pocitos, Guatemala, Central America, June 2010

Guy Edwardes / View of pipework and Geothermal power plant, Reykjanesvirkjun, South West Iceland, July 2009

Guy Edwardes / View of pipework and Geothermal power plant, Reykjanesvirkjun, South West Iceland, July 2009

Sergey Gorshkov / Steam emitted from geysers, Geyser River, Valley of Geysers, Kamchatka, Russia

Sergey Gorshkov / Steam emitted from geysers, Geyser River, Valley of Geysers, Kamchatka, Russia

Sergey Gorshkov / Geyser River and geysers in background, Valley of Geysers, Kamchatka, Russia

Sergey Gorshkov / Bubbling geothermal mud pool, Kamchatka, Russia

Chadden Hunter / Dallol hot springs where water heated by magma laden with potassium, sulphur and iron spews up through salt pans staining the salt deposits with vivid colours, in the bottom of the Rift Valley, 120 me...

Uri Golman / Helicopter flying over volcanic eruption near Eyjafjallajoekull glacier, Iceland, 24th March 2010. Volcano previously dormant since 1821.

Juan Carlos Munoz / Eyjafjallajkull volcano erupting, Fimmvruhls area, Iceland, 7th of April 2010

Juan Carlos Munoz / Eyjafjallajkull volcano erupting, Fimmvruhls area, Iceland, 7th of April 2010

Juan Carlos Munoz / Eyjafjallajökull volcano erupting, Fimmvörðuháls area, Iceland, 7th of April 2010

Juan Carlos Munoz / Eyjafjallajökull volcano erupting, Fimmvörðuháls area, Iceland, 7th of April 2010

Juan Carlos Munoz / Eyjafjallajkull volcano erupting, Fimmvruhls area, Iceland, 5th of April 2010

Juan Carlos Munoz / Eyjafjallajökull volcano erupting, Fimmvörðuháls area, Iceland, 7th of April 2010

Jeff Vanuga / Dead Thermal Spider encased in thermophilic bacteria in hot Spring, Yellowstone National Park, Wyoming, USA, October

Jeff Vanuga / Bull Bison (Bison bison) warming himself in the steam from the Firehole River, Upper Geyser Basin, Yellowstone National Park, Wyoming, USA, January

Jeff Vanuga / Boiling mud in Pocket Basin, Yellowstone National Park, Wyoming, USA, June 2006

Jeff Vanuga / Lone Star Geyser erupting in Lone Star Geysyer Basin at night, Yellowstone National Park, Wyoming, USA, October 2007

Wild Wonders of Europe / Grunewald / Sulphurous fumaroles (solfatara) Vulcano Island, Italy, May 2009

Inaki Relanzon / Tourists watching eruption of The Strokkur, the biggest geyser active in the Geysir area, SW Iceland, sequence 6/11. July 2008

Inaki Relanzon / Tourists watching eruption of The Strokkur, the biggest geyser active in the Geysir area, SW Iceland, sequence 2/11. July 2008

Jouan & Rius / People bathing in the spa waters of the Blue Lagoon with the geothermal power plant in the background, Grindavik, Iceland 2005

Jouan & Rius / Pipes carrying heated water from the geothermal power plant in Krafla volcano area, northern Iceland 2005

Yukihiro Fukuda / Japanese macaque (Macaca fuscata) eight months old sitting in front of a pool created by a hot spring being used by females and young for bathing to keep warm, Jigokudani, Joshinetsu Kogen NP, Nagano...

Yukihiro Fukuda / Female Japanese macaques (Macaca fuscata) in a hot spring to keep warm, only females and young bathe, Jigokudani, Joshinetsu Kogen NP, Nagano, Japan

Yukihiro Fukuda / Japanese macaque (Macaca fuscata) holding young while bathing in hot spring to keep warm, only females and young bathe, winter, Jigokudani, Joshinetsu Kogen NP, Nagano, Japan

Yukihiro Fukuda / Japanese macaques (Macaca fuscata) warming up by bathing in a hot spring during snowfall, only females and young bathe, Jigokudani, Joshinetsu Kogen NP, Nagano, Japan

Wild Wonders of Europe / O Haarberg / Volcanic activity, Steam vent at Hverir, Nmafjall, Iceland, July 2008

Wild Wonders of Europe / O Haarberg / Boiling mudpool, volcanic activity, Hverir, Nmafjall, Iceland, July 2008

Wild Wonders of Europe / O Haarberg / Hot springs with sulpur deposits, Leirhnjkur, Iceland, July 2008

Orsolya Haarberg / Acidic steam and solidified lava surface at Leirhnjkur. Iceland. July 2008

Wild Wonders of Europe / O Haarberg / Steam vent, Rhyolite / Rhiolite mountains, Landmannalaugar, Iceland, June 2008

Wild Wonders of Europe / O Haarberg / Acidic steam and solidified lava surface at Leirhnjkur, Iceland, June 2008

Wild Wonders of Europe / O Haarberg / Boiling mudpool, Hverir, Nmafjall, Iceland, June 2008

Orsolya Haarberg / Steam vents and sulphur deposit at Hverir. Nmafjall, Iceland. June 2008

Orsolya Haarberg / Rhiolite mountains at Landmannalaugar. Rhyiolite volcanism. Iceland. June 2008

Orsolya Haarberg / Steam vent at Hverir. Nmafjall, Iceland. June 2008

Wild Wonders of Europe / O Haarberg / Boiling mudpool, volcanic activity, Hverir, Nmafjall, Iceland, July 2008

Wild Wonders of Europe / O Haarberg / Boiling mudpool, volcanic activity, Hverir, Nmafjall, Iceland, July 2008

Yva Momatiuk & John Eastcott / Great Fountain Geyser erupting, Yellowstone National Park, Wyoming

Pete Oxford / Galapagos Giant Tortoise (Geochelone elephantophus vandenburghi) near fumaroles, Alcedo Volcano crater floor, Isabela Island, Galapagos Islands

Pete Oxford / Geothermal activity as evidenced by bubbles eminating from the seabed, Roca Redonda and eroded volcano in mid ocean north of Isabela Island, Galapagos Islands, Ecuador, South America

Yukihiro Fukuda / Japanese macaque / Snow monkey {Macaca fuscata} 7-month-old monkey bathing in hot springs, examining its hands, water at 40 degrees, Jigokudani, Nagano, Japan

Yukihiro Fukuda / Japanese macaque / Snow monkey {Macaca fuscata} adult female bathing in hot springs tapping the water surface with hand in play, water at 40 degrees, Jigokudani, Nagano, Japan

Yukihiro Fukuda / Japanese macaque / Snow monkey {Macaca fuscata} group of monkeys bathing in hot springs, water at 40 degrees, Jigokudani, Nagano, Japan

Igor Shpilenok / Velikan (or "Giant") Geyser, the largest geyser on Kamchatka, periodically shooting to a height of a nine-story building and releasing 30 tons of water per minute. Colonies of thermophilic bacteria co...

Igor Shpilenok / A hot spring ringed by thermophilic bacteria in the vast caldera of the Uzon Volcano, Kronotsky Zapovednik, Kamchatka, Far East Russia .

Igor Shpilenok / Steaming fissures and geysers in the caldera of Uzon Volcano, Kronotsky Zapovednik, Kamchatka, Far East Russia

Jeff Vanuga / Blue Funnel Spring, West Thumb Geyser Basin, Yellowstone Nationa Park, Wyoming, USA

Pete Oxford / Dead trees in Mammoth Hot Springs travertine terraces, Yellowstone National Park, Wyoming

Jabruson / Volcanic eruption of Kimanura volcano, 1989, Democratic Republic of Congo

Jack Dykinga / Morning Glory pool with Lodgepole pines {Pinus contorta} in background, Yellowstone NP, Wyoming, USA

Doug Perrine / Lava flowing from Lae'apuki bench into the sea during Pu'u O'o eruption, Kilauea Volcano, Hawaii, Jan 2000

Igor Shpilenok / Boiling red clay mud pots with steam, caused by underground volcanic activity, Valley of the Geysers, Kronotsky Zapovednik Reserve, Russia.

Igor Shpilenok / Kamchatka Brown bear (Ursus arctos beringianus) skirting a steaming thermal field, Valley of the Geysers, Kronotsky Zapovednik Reserve, Kamchatka, Russia.

Igor Shpilenok / Kamchatka Brown bear (Ursus arctos beringianus) walking along the Valley of the Geysers, Kronotsky Zapovednik Reserve, Kamchatka, Russia.

Igor Shpilenok / The 'Fireplace' rock formation, Geyser River, Valley of the Geysers, Kronotsky Zapovednik Reserve, Russia.

Igor Shpilenok / Spring in the caldera of the Uzon Volcano, Kronotsky Zapovednik Reserve, Russia.

Igor Shpilenok / Kamchatka Brown bear (Ursus arctos beringianus) resting on warm ground next to thermal waters, Valley of the Geysers, Kronotsky Zapovednik Reserve, Kamchatka, Russia.

Sue Flood / Morning Glory Pool, Yellowstone National Park, Wyoming, USA

Pete Cairns / Line of Bison {Bison bison} geysers steaming, Yellowstone National Park, USA.

Pete Cairns / Morning glory pool, Old Faithful geyser, Yellowstone NP, Wyoming, USA

Pete Oxford / Sol de Manana fumeroles geothermal activity at 4850 metres Altiplano, SW Bolivia

Jim Brandenburg / Morning Glory pool in Upper Geyser Basin, Yellowstone National Park, Wyoming

Jim Brandenburg / Aerial view of Grand Prismatic Pool in winter, Midway Geyser Basin, Yellowstone National Park, Wyoming

Pete Cairns / Landscape with Bison {Bison bison} and steam from geysers, Yellowstone NP, Wyoming, USA

Juergen Freund / Volcano erupting with laval flow. Siau island Sangihe Talaud Is Sulawesi Indonesia

Hermann Brehm / Grand Prismatic Spring in Midway Geyser Basin, Yellowstone NP, Wyoming, USA.

Miles Barton / Portrait of 'Tokiwa', the first macaque to get into the hot spring, Japan. Photographed while filming for A Monkey for All Seasons.

Juergen Freund / Siau volcano erupting with moon behind, N Sulawesi, Indonesia

Neil Lucas / Geyser known as Strokkur (the churn) blows once every 20-30 minutes. Iceland, Europe

Michele Westmorland / Volcanic bubbles escaping from the sea bed, Sangeang Island, Indonesia.

Gavin Hellier / The Blue Lagoon, Iceland's most famous tourist attraction is located among the black lava flows outside Reykjavik. The geothermal spa owes its existence to the Svartsengi geothermal power plant powere...

Gavin Hellier / The Blue Lagoon, Iceland's most famous tourist attraction is located among the black lava flows outside Reykjavik. The geothermal spa owes its existence to the Svartsengi geothermal power plant powere...