Bryan and Cherry Alexander / Dramatic 'Undulatus asperatus' cloud formation as a storm builds at dawn over Qaanaaq, Inglefield Bay. Northwest Greenland, September 2008. This cloud formation was first proposed as a new type of clo...

Bryan and Cherry Alexander / Inuit hunters trying to stop lead opening using their harpoons. Northwest Greenland, 1977.

Bryan and Cherry Alexander / Dramatically eroded cliffs reflected in the waters of Hall Basin. Ellesmere Island, Nunavut, Canada.

Bryan and Cherry Alexander / Looking along a cloudy Lilliehookfjorden to the sun shining on mountains in Krossfjorden. Spitsbergen, Svalbard, Norway, June 2008.

Bryan and Cherry Alexander / Reflections of glaciers, clouds and mountains in Burgerbukta. Hornsund Fjord, Spitsbergen, Svalbard, Norway, June 2008.

Bryan and Cherry Alexander / Thawing sea ice at the mouth to Brepollen Fjord, against snow-covered mountains. Spitsbergen, Svalbard, Norway, June 2008.

Bryan and Cherry Alexander / Thawing sea ice at the mouth to Brepollen Fjord, against snow-covered mountains. Spitsbergen, Svalbard, Norway, June 2008.

Bryan and Cherry Alexander / Dramatic 'Undulatus asperatus' cloud formation as a storm builds at dawn over Qaanaaq, Inglefield Bay. Northwest Greenland, September 2008. This cloud formation was first proposed as a new type of clo...

Bryan and Cherry Alexander / Dramatic 'Undulatus asperatus' cloud formation as a storm builds at dawn over Qaanaaq, Inglefield Bay. Northwest Greenland, September 2008. This cloud formation was first proposed as a new type of clo...

Bryan and Cherry Alexander / Dramatic 'Undulatus asperatus' cloud formation as a storm builds at dawn over Qaanaaq, Inglefield Bay. Northwest Greenland, September 2008. This cloud formation was first proposed as a new type of clo...

Bryan and Cherry Alexander / Dramatic 'Undulatus asperatus' cloud formation as a storm builds at dawn over Qaanaaq, Inglefield Bay. Northwest Greenland, September 2008. This cloud formation was first proposed as a new type of clo...

Bryan and Cherry Alexander / Dramatic 'Undulatus asperatus' cloud formation as a storm builds at dawn over Qaanaaq, Inglefield Bay. Northwest Greenland, September 2008. This cloud formation was first proposed as a new type of clo...

Bryan and Cherry Alexander / Dramatic 'Undulatus asperatus' cloud formation as a storm builds at dawn over Qaanaaq, Inglefield Bay. Northwest Greenland, September 2008. This cloud formation was first proposed as a new type of clo...

Bryan and Cherry Alexander / Icebergs and small pieces of glacial ice floating in Inglefield Bay at sunset. Northwest Greenland, September 2008.

Bryan and Cherry Alexander / Chukchi reindeer herders putting cover on their Yaranga (traditional tent). Chukotskiy Peninsula, Chukotka, Siberia, Russia, spring 2010

Bryan and Cherry Alexander / Chukchi reindeer herders putting cover on their Yaranga (traditional tent). Chukotskiy Peninsula, Chukotka, Siberia, Russia, spring 2010

Bryan and Cherry Alexander / Iceberg in a calm sea, Scoresbysund Fjord, East Greenland, September 2005.

Bryan and Cherry Alexander / Nenets herders making a lasso from Reindeer / Caribou skin at summer camp. Yamal, Western Siberia, Russia, 2000.

Bryan and Cherry Alexander / Inuit hunters working as team to haul dead Walrus (Odobenus rosmarus) onto sea ice. Northwest Greenland, 1977

Bryan and Cherry Alexander / Inuit hunters hauling seal onto fast ice. Qaanaaq, Northwest Greenland, 1971. Wearing polar bearskin trousers

Bryan and Cherry Alexander / Inuit hunter using kayak to retrieve seal shot at ice edge in winter. Thule, Northwest Greenland, 1980.

Bryan and Cherry Alexander / Swedish couple in honeymoon suite of Ice Hotel, Jukkasjarvi, Sweden, 1993.

Bryan and Cherry Alexander / Mountains and altocumulus clouds reflected in Hall Basin. Ellesmere Island, Nunavut, Canada.

Bryan and Cherry Alexander / Park warden on patrol at Tanquary Fiord. Ellesmere Island, National Park Reserve, Canada, 1994.

Bryan and Cherry Alexander / Polar bear (Ursus maritimus) mother standing over her mauled cub after it was attacked by large male. Cape Churchill, Manitoba, Canada.

Bryan and Cherry Alexander / Woman using an outdoor toilet screened from the wind by a wall of snowblocks. Nunavut, Canada, 1999.

Bryan and Cherry Alexander / Midnight sun reflected in calm sea off Igloolik Island. Nunavut, Canada, July, 1992.

Steven Kazlowski / Polar bear (Ursus maritimus) cub watches as a plane flies overhead, Barter Island and the 1002 coastal plain of the Arctic National Wildlife Refuge, Alaska

Steven Kazlowski / Polar bear (Ursus maritimus) cub on newly formed pack ice watches a plane fly overhead, off Barter Island and the 1002 area of the Arctic National Wildlife Refuge, Alaska

Tom Vezo / Polar bears sparring {Ursus maritimus}. Churchill, Manitoba.

Eric Baccega / Small iceberg in the fog, Sunshine fjord, Baffin Island, Nunavut, Canada, August 2010

Eric Baccega / Small iceberg in the fog, Sunshine fjord, Baffin Island, Nunavut, Canada, August 2010