Long-term changes (trends) in short-term (day-to-day to intraseasonal) variability of
temperature and precipitation are examined in the Northern Extratropics, both in the observed
data and in outputs of global and regional climate models. Various characteristics of variability,
which provide complementary information, are analyzed (standard deviation, persistence, dayto-
day variations, transition probabilities, lengths of dry and wet spells). Their climatologies and
trends are compared between different dataset types (station, gridded, reanalysis) with the aim
to identify biases specific to individual dataset types. We also focus on mechanisms governing
the short-term variability, and the day-to-day temperature changes in particular, in which
atmospheric fronts are likely to play a role. We validate the short-term variability in climate
model outputs and evaluate its future projections by models. Finally, we attempt to find out
whether the anthropogenic climate change is already manifested in the recently observed
changes of variability
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