  While the warming trends of the Earth's mean temperature are evident at
climatological scales, the local temperature at shorter timescales are highly
fluctuating. In this letter we show that the probabilities of such fluctuations
are characterized by a special symmetry typical of systems out of equilibrium.
Their nearly universal properties are linked to the fluctuation theorem and
reveal that the progressive warming is accompanied by growing asymmetry of
temperature distributions. These statistics allow us to project the global
temperature variability in the near future, in line with predictions from
climate models, providing valuable information about future extremes.
