| Summary: | International audience We describe the mass balance of Langjökull ice cap, Iceland, (∼920 km²), ∼190 km^3) during several time intervals of different climate conditions that span the 20th century until present. The elevation range of Langjökull is 460-1440 m a.s.l. with a zero mass balance equilibrium line altitude (ELA) of 1000 m (southern outlets). The mass balance of the ice cap has been observed in situ every year since 1996-1997 and also assessed from estimation of glacier volume changes by comparing series of elevation maps from: 1937, 1945-1946, 1986, 1997 and 2004. The glacier margin of the Little Ice Age maximum (LIA; ∼1890) was estimated from the location of end moraines. The difference between the 1997-2004 annnual specific net balance estimated by volume change and in situ measurements is negligible (∼5 cmwe). During the two warm periods 1936-1946 and 1997-2009 the mean mass balance was similar; -1.6 and -1.3 m we/yr, respectively. The colder climate during 1946-1986 and cooler yet in 1986-1997 resulted in specific mass balance close to zero; -0.3 and -0.2 m we/yr, respectively.
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