Tony Heald / Glaucous Gull (Larus hyperboreus) taking off from ice, Svalbard Norway, July.

Jordi Chias / Leopard seal (Hydrurga leptonyx) resting over an iceberg, Antarctic Peninsula, Antarctica.

Jordi Chias / Gentoo penguins (Pygoscelis papua) swimming together and porpoising in search of krill, Antarctic Peninsula, Antarctica.

Danny Green / Sea otter (Enhydra lutris) resting on sea ice, Alaska, USA, June

Danny Green / Sea otter (Enhydra lutris) resting amongst sea ice, Alaska, USA, June

Danny Green / Sea otters (Enhydra lutris) resting on ice, Alaska, USA, June

David Tipling / Snow petrel (Pagadroma nivea nivea) flying around Iceberg off South Georgia, Southern Ocean January

Frederique Olivier / Adelie penguins (Pygoscelis adeliae) swimming underneath sea ice, Antarctica.

Frederique Olivier / Wide-angle shot of a group of Emperor penguin (Aptenodytes forsteri) chicks walking on sea ice, Adelie Land, Antarctica, January.

Frederique Olivier / Emperor penguin (Aptenodytes forsteri) chick begging for food from parent, Adelie Land, Antarctica, January.

Frederique Olivier / Emperor penguin (Aptenodytes forsteri) walking with chick, Adelie Land, Antarctica, January.

Frederique Olivier / Close-up of a group of Emperor penguin (Aptenodytes forsteri) chicks huddled together in a blizzard, covered in snow, Adelie Land, Antarctica, January.

Frederique Olivier / Emperor penguin (Aptenodytes forsteri) chicks huddled together during a blizzard, Adelie Land, Antarctica, January.

Frederique Olivier / Emperor penguins (Aptenodytes forsteri) walking in blizzard, Adelie Land, Antarctica, January.

Frederique Olivier / Emperor penguins (Aptenodytes forsteri) walking and tobogganing in blizzard, Adelie Land, Antarctica, January.

Frederique Olivier / Emperor penguin (Aptenodytes forsteri) chicks calling, with another small chick arriving and falling over, Adelie Land, Antarctica, January.

Frederique Olivier / Group of Adelie penguins (Pygoscelis adeliae) swimming in a tide crack, lots jump out, Adelie Land, Antarctica, January.

Frederique Olivier / Wide angle shot of Adelie penguins (Pygoscelis adeliae) walking on sea ice, Adelie Land, Antarctica, January.

Frederique Olivier / Adelie penguins (Pygoscelis adeliae) walking in front of a blue iceberg, Adelie Land, Antarctica, January.

Peter Bassett / King penguins (Aptenodytes patagonicus) walking towards and entering the sea near their breeding colony, Salisbury Plain, South Georgia.

Frederique Olivier / Emperor penguin (Aptenodytes forsteri) tobogganing on an iceberg at sunset and diving from the edge, seen from a moving boat, Antarctica.

Frederique Olivier / Group of Adelie penguins (Pygoscelis adeliae) diving from the edge of the sea ice, Antarctica.

Frederique Olivier / Group of Adelie penguins (Pygoscelis adeliae) walking away from the camera on sea ice at sunset, with one solitary penguin in the foreground, Antarctica.

Frederique Olivier / Group of Adelie penguins (Pygoscelis adeliae) running and gathered on sea ice, Antarctica.

Frederique Olivier / Adelie penguin (Pygoscelis adeliae) colony, with icebergs and pack ice in the background, Antarctica.

Frederique Olivier / Adelie penguins (Pygoscelis adeliae) diving, seen from underwater, Antarctica.

Ingo Arndt / Emperor penguins (Aptenodytes forsteri) Weddell Sea, Antarctica

Danny Green / Three Sea otters (Enhydra lutris) resting on ice, Alaska, June

Brent Stephenson / Sunset off Scott Island, with floating pieces of sea ice, Scott Inlet, Baffin Island, Canadian Arctic, August 2015.

Sven Zacek / Broken ice covered in snow at sunset, on the shore of Lake Vortsjarv, gathered to shore by extreme winds, Estonia. December 2014.

Bryan and Cherry Alexander / Chinstrap penguins (Pygoscelis antarctica) on a blue iceberg, with Antarctic Prion (Pachyptila desolata) flying over. Antarctica

Ben Cranke,Ben Cranke / Gentoo Penguin (Pygoscelis papua) penguins rest on a floating iceberg, Antarctic Peninsula, Antarctica

Ben Cranke,Ben Cranke / Gentoo Penguin (Pygoscelis papua) group travelling out to sea, Cuverville Island, Antarctic Peninsula, Antarctica

Orsolya Haarberg / Arctic tern (Sterna paradisaea), adult feeding young. Jokulsarlon glacial lagoon. Iceland. August 2008

Steven Kazlowski,Steven Kazlowski / Polar bear (Ursus maritimus) curious adult head underwater, Beaufort Sea, off the 1002 area of the Arctic National Wildlife Refuge, North Slope, Alaska.

Steven Kazlowski,Steven Kazlowski / Polar bear (Ursus maritimus) 4-5 year-old on pack ice, low angle shot, off the 1002 area of the Arctic National Wildlife Refuge, North Slope of the Brooks Range, Alaska, Beaufort Sea, autumn

Danny Green / Fulmer (Fulmras glacialis) in flight near blue glacier, Svalbard, July. Bookplate from Danny Green's 'The Long Journey North'

David Tipling / Chinstrap Penguins (Pygoscelis antarcticus) on blue iceberg, Antarctica

Staffan Widstrand / Brunnich's Guillemot (Uria lomvia) stretching wings and calling on small ice floe, Svalbard, Norway, July

Enrique Lopez-Tapia / Leopard seal (Hydrurga leptonyx) resting on iceberg, Gerlache Strait, Antarctic Peninsula, Antarctica, March 2010. WINNER OF NATURE CATEGORY OF POLLUX COMPEITITON / AWARDS 2013

Chadden Hunter / Brinicles (brine icicles or ice stalactites) forming under the ice, growing towards the sea floor, Ross Sea, McMurdo Sound, Antarctica. Taken on location for 'Winter' episode of the BBC Frozen Planet...

Roy Mangersnes / Black-legged kittiwakes (Rissa tridactyla) in flight during evening snowfall, Northern Nordaustlandet, Svalbard, Norway, August

Roy Mangersnes / Juvenile Black-legged kittiwake (Rissa tridactyla) flying over Raudfjorden, North-western tip of Spitsbergen, Svalbard, Norway, September

Mark Carwardine / Three Gentoo Penguins (Pygoscelis papua) standing at the edge of sea ice. Antarctic Peninsula, January. Book plate from Mark Carwardine's Ultimate Wildlife Experiences.

Mark Carwardine / Chinstrap Penguins (Pygoscelis antarcticus) standing on ice. South Shetland Islands, Antarctica, January. Book plate from Mark Carwardine's Ultimate Wildlife Experiences.

Chadden Hunter / King penguins (Aptenodytes patagonicus) walk along beach, South Georgia. Taken on location for BBC Frozen Planet series, 2008

Chadden Hunter / Emperor penguins (Aptenodytes forsteri) explode out of the water, returning to breed at Cape Washington, Antarctica. Taken on location for BBC Frozen Planet series, 2009

Chadden Hunter / Emperor penguins (Aptenodytes forsteri) males dive through openings in the sea ice to take their first swim in over 4 months as they have spent the bleak winter incubating their eggs. Cape Washington,...

Doug Allan / Killer Whales (Orcinus orca) spy-hopping to observe Weddell Seal (Leptonychotes weddellii) in preparation to knock it from the ice by creating a wave. Marguerite Bay, Antarctic Peninsula, summer. Free...

Eric Baccega / Portrait of Harp seal (Phoca groenlandicus) pup, Magdalen Islands, Gulf of St Lawrence, Quebec, Canada, March 2012

Andy Rouse / Polar ice cap at sunset. Austfonna Polar Ice Cap, Svalbard, Norway, August 2011.

Ole Jorgen Liodden / Black-legged Kittiwake (Rissa tridactyla) in blue ice. Spitsbergen, Svalbard, July.

Ole Jorgen Liodden / Glaucous Gull (Larus hyperboreus) on blue ice. Spitsbergen, Svalbard, July.

Steven Kazlowski / Polar bear (Ursus maritimus) curious adult investigates a remote camera along a hillside on Spitsbergen and the northwest coast of the Svalbard Archipelago, Norway, Greenland Sea, July

Kathryn Jeffs / Adelie penguins (Pygoscelis adeliae) on ice floe, Antarctica. Taken on location for BBC Frozen Planet series, January 2009

Kathryn Jeffs / Adelie penguins (Pygoscelis adeliae) on ice floe, Antarctica. Taken on location for BBC Frozen Planet series, January 2009

Frederique Olivier / Young Emperor penguins (Aptenodytes forsteri) jumping off ice floes, Antarctica, February 2011.

Jeff Wilson / Emperor penguin (Aptenodytes forsteri) adults and chicks in colony beside ice cliff, Cape Crozier, Antarctica, November 2009. Taken on location for BBC series, Frozen Planet, Spring.

Danny Green / Little Auks (Alle alle) flying low above surface in front of iceberg. Spitsbergen, Svalbard, Norway, July 2010. Highly commended in the Birds category in the GDT competition 2011.

Bence Mate / Great egret (Ardea alba) drops a fish from its beak and a Black headed gull (Larus ridibundus) flies in to catch it. Lake Csaj, Kiskunsagi NP, Hungary, January. Winner, Eric Hosking award, 2011 Wildli...

Bryan and Cherry Alexander / Adelie penguin (Pygoscelis adeliae) on snow bank at Prospect Point with the mountains of Renaud Island beyond. Antarctica.

Bryan and Cherry Alexander / Emperor penguin (Aptenodytes forsteri) chicks playing with a piece of ice as they wait for their next meal. Snow Hill Island, Antarctica, October.

Bryan and Cherry Alexander / Emperor penguin (Aptenodytes forsteri) chick by a line of photographers. Snow Hill Island, Antarctica, October.

Bryan and Cherry Alexander / Emperor penguin (Aptenodytes forsteri) chick spreads tiny wings next to parent. Snow Hill. Antarctica, October.

Bryan and Cherry Alexander / Emperor penguin (Aptenodytes forsteri) chick leaning on parent, Snow Hill Island, Antarctica, October.

Bryan and Cherry Alexander / Curious Emperor penguin (Aptenodytes forsteri) chicks with adults in the Snow Hill Island colony. Antarctica, October 2006.

Eric Baccega / Black-legged Kittiwake (Rissa tridactyla) on ice. Floe edge, Arctic Bay, Nunavut, Canada, April.

Troels Jacobsen/Arcticphoto / Adelie Penguins (Pygoscelis adeliae) diving into the water, on their way out to sea to feed. Brown Bluff. Antarctic Peninsula.

Bryan and Cherry Alexander / Line of Emperor penguins (Aptenodytes forsteri) walking on sea ice. Flutter Rookery, East Antarctica.

Charlie Summers / Adelie Penguin (Pygoscelis adeliae) flapping its flippers to cool down, Cuverville Island, Antarctica, November

Charlie Summers / Gentoo Penguin (Pygoscelis papua) diving off iceberg and into waters of Pleneau Bay, Antarctica, November

Kevin Schafer / Kittiwake (Rissa tridactyla) flock feeding in from of the Monaco Glacier, Leifdefjord, Svalbard, Norway 2010

Eric Baccega / View across the bow of the Lyubov Orlova ship, moving through pack ice at dawn, off the coast of Devon Island. Nunavut, Canada, August 2010

Nick Garbutt / Arctic tern (Sterna Paradisaea) hovering in flight over an iceberg.Peterman Island, Antarctic Peninsula, Antarctica. February.

Nick Garbutt / Flock of Kelp / Southern black backed Gulls (Larus dominicanus) flying over iceberg. Graham Passage, Antarctic Peninsula, Antarctica. February. (digitally altered image)

Charlie Summers / Adelie penguin (Pygoscelis adeliae) hopping from ice block to ice block, Petermann Island, Antarctica

Tim Laman / Adelie penguins (Pygoscelis adeliae) on iceberg, Antarctica, January

Steven Kazlowski / Atlantic puffin (Fratercula arctica) flying along the coast of Svalbard in summer, Norway

Neil Lucas / Weddell seal (Leptonychotes weddellii) face emerging through sea ice, Ross Sea, Antarctica, November 2008

Neil Lucas / Weddell seal (Leptonychotes weddellii) male surfacing in ice hole, McMurdo Sound, Ross Sea, Antarctica, November 2008

Eric Baccega / Cable car over Mer de Glace glacier, Mont Blanc, Alps, France, July 2001

Uri Golman / Sunset over iceberg. Jakobshavn, Ilulissat, Kangia, Icefjord, Greenland. August 2006.

Sue Flood / Emperor penguin (Aptenodytes forsteri) walking across ice, Snow Hill Island rookery, Weddell Sea, Antarctica, November

Dietmar Nill / Grey heron (Ardea cinerea) with fish being attacked by Gull, Germany, winter

Sue Flood / Emperor penguins (Aptenodytes forsteri) adults and chicks on ice, Cape Washington, Ross Sea, Antarctica, December

Wild Wonders of Europe / de la Lez / Black legged kittiwakes (Rissa tridactyla) in flight over ice, Kungsfjord, Svalbard, Norway, June 2008 Wild Wonders kids book.

Wild Wonders of Europe / Liodden / Brunnich's guillemots (Uria lomvia) on ice, Spitsbergen, Svalbard, June 2009 WWE BOOK Wild Wonders kids book.

Wild Wonders of Europe / Liodden / Two Glaucous gulls (Larus hyperboreus) flying past a glacier, Spitsbergen, Svalbard, March 2009

David Tipling / Steller's sea eagle {Haliaeetus pelagicus} off Rausu, Shiretoko Peninsula, Hokkaido, Japan, February

Andy Rouse / Arctic Tern (Sterna paradisaea) flying past an iceberg, Svalbard, Norway

Andy Rouse / Gentoo penguin (Pygoscelis papua) group on iceberg, one calling, Mikkelsen Harbour, Antarctica

Andy Rouse / Gentoo penguins (Pygoscelis papua) swimming near the shore, Neko Harbour, Antarctica

Andy Rouse / Gentoo penguin (Pygoscelis papua) group on iceberg, one calling, Mikkelsen Harbour, Antarctica

Michael Pitts / Kittiwake {Rissa tridactyla} flying over arctic ice cap

Steven Kazlowski / Polar bear (Ursus maritimus) climbing onto an iceberg with Arctic terns {Sterna paradisaea} flying overhead, Beaufort Sea, Arctic Ocean, Alaska