Ashley Cooper / Raise Beck above Dunmail Raise, with large snow drift, Lake District, England, UK, April.

Ashley Cooper / Gentoo penguins (Pygoscelis papua) with members of an expedition cruise ship. Curverville Island, Antarctic Peninsula.

Martin Gabriel / Accumulation of land snails (Euryptyxis labiosa) escaping the desert heat by resting on a twig, Ayn Sahnawt, Sultanate of Oman, February.

Martin Gabriel / Accumulation of land snails (Euryptyxis labiosa), escaping the desert heat by resting on a shrub's bark, Ayn Sahnawt, Sultanate of Oman, February.

Alex Hyde / Natural accumulation of mollusc shells, mainly bivalves including a Queen scallop (Aequipecten / Chlamys opercularis), washed up on the strand line, Anglesey, Wales, UK. December.

Alex Hyde / Natural accumulation of mollusc shells, mainly bivalves, washed up on the strandline, Anglesey, Wales, UK. December.

Jenny E. Ross / Arctic tundra with frost-wedging features caused by repeated freeze-thaw processes in rocky soil, and surface water accumulation from melting permafrost. Wrangel Island, Siberian Arctic, Chukchi Sea,...

Jenny E. Ross / Arctic tundra with frost-wedging features caused by repeated freeze-thaw processes in rocky soil, and surface water accumulation from melting permafrost. Wrangel Island, Siberian Arctic, Chukchi Sea,...

Jenny E. Ross / Arctic tundra with frost-wedging features caused by repeated freeze-thaw processes in soil, as well as slumping and and surface water accumulation from thawing permafrost. Amguema River Estuary Region...