Tsar Bomba C), north of the Arctic Circle over the Novaya Zemlya archipelago in the Arctic Ocean. The bomb was dropped from an altitude of ; it was designed to detonate at a height of over the land surface ( above sea level) by barometric sensors. The original, November 1961, United States Atomic Energy Commission estimate of the yield was 55–60 megatons, but since 1992, all Russian sources have stated its yield as 58.6 megatons. First secretary Khrushchev warned in a filmed speech to the Supreme Soviet of the existence of a 100-megaton bomb (technically the design was capable of this yield.)
Severnaya Zemlya to a survey of prior observations by De Korte, Volkov, and Gavrilo, thirty-two bird species have been observed on Severnaya Zemlya, 17 of which are known to breed on the islands. Eight species are widespread across the archipelago: five of which are colonial seabirds: little auk ("Alle alle"), black-legged kittiwake ("Rissa tridactyla"), black guillemot ("Cepphus grylle"), ivory gull ("Pagophila eburnea"), and glaucous gull ("Larus hyperboreus"); and three species of tundra bird: the snow bunting ("Plectrophenax nivalis"), purple sandpiper ("Calidris maritima"), and brent goose ("Branta bernicla"). The most common mammal on Severnaya Zemlya is the collared lemming ("Dicrostonyx torquatus"), also known