Talk by Dr Frank Kwasniok – Niels Bohr Institute - University of Copenhagen

Niels Bohr Institute > Calendar > 2011 > Talk by Dr Frank Kwasniok

Talk by Dr Frank Kwasniok

Regime-dependent modelling of extremes in the extratropical atmospheric circulation: statistics, prediction and predictability

The talk discusses data-based statistical-dynamical models of wind speed
and vorticity extremes in the extratropical atmospheric circulation. The
models are formulated conditional on the large-scale flow regime of the
atmosphere by combining the estimation of the model parameters with a
clustering algorithm. Firstly, the statistical behaviour of extremes is
characterised by estimating generalised extreme value (GEV) distribution
parameters as a function of space and the large-scale flow regime.
Secondly, predictive models for individual extreme events are built and
their predictive skill is studied. Prediction and predictability of
extreme events are investigated as a function of initial condition,
event rarity and event magnitude. The study is performed using a
three-level quasigeostrophic atmospheric model with realistic mean
state, variability and teleconnection patterns as dynamical framework.