Bryan and Cherry Alexander / Sundogs (parhelia / parhelai) behind a 'Christmas tree' (valve assembly) in the South Tambey Gas Field, Yamal Peninsula, Siberia, Russia. February 2014.

Bryan and Cherry Alexander / A gas drilling derrick at sunset in the South Tambey Gas Field, Yamal Peninsula, Siberia, Russia. February 2014.

Bryan and Cherry Alexander / Grisha (right) and Gosha Vanuitto, Nenets reindeer herders, at their winter camp on the tundra in the South Tambey Gas Field, Yamal Peninsula, Siberia, Russia. February 2014.

Bryan and Cherry Alexander / A 'Christmas tree' (valve assembly) in front of a gas drilling derrick in the South Tambey Gas Field, Yamal Peninsula, Siberia, Russia. February 2014.

Bryan and Cherry Alexander / Oil storage tanks near Sabetta, South Tambey Gas field, Yamal, Siberia, Russia. February 2014.

Bryan and Cherry Alexander / Chukchi girls, with their family's ancestral clan mark painted in reindeer blood on their face, a ritual during the Chukchi 'Festival of the Young Reindeer' during which young reindeer are sacrificed....

Bryan and Cherry Alexander / Emperor penguins (Aptenodytes forsteri) colony, with Snow petrel (Pagodroma nivea) flying past and dark sky. Atka Bay. Antarctica

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

Bryan and Cherry Alexander / Icicles hanging from the edge of a small blue iceberg as the summer thaw sets in, Antarctica

Bryan and Cherry Alexander / Inuit hunter travelling by dog sled during the polar night. Northwest Greenland, 1987. 40 BELOW bookplate.

Bryan and Cherry Alexander / Inuit man pulling aside igloo door at dusk. Igloolik, Nunavut, Canada, 1993. 40 BELOW bookplate.

Bryan and Cherry Alexander / Moonlit iceberg taken at midday during the polar night, Northwest Greenland, 1980. 40 BELOW bookplate.