Hans von Storch

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The utility of long-term reconstructions with
regional climate/earth system models

• Hans von Storch
• Institute for Coastal Research, GKSS Research
  Center, Germany
• and KlimaCampus, U of Hamburg, Germany

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What is coastDat?
A set of model data(hindcasts, reconstructions
and scenarios for the future) Based on
experiences and activities in a number of
national andinternational projects (e.g. WASA,
HIPOCAS, STOWASUS, PRUDENCE) Presently contains
atmospheric and oceanographic parameter(e.g.
near-surface winds, pressure, temperature and
humidity upper air meteorological data such as
geopotential height, cloud cover, temperature and
humidity oceanographic datasuch as sea states
(wave heights, periods, directions, spectra) or
water levels (tides and surges) and depth
averaged currents, ocean temperatures) Covers
different geographical regions(presently mainly
the North Sea and parts of the Northeast
Atlantic other areas such as the Baltic Sea,
polar regions or SE-Asia are to be included)
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• Overview
• Construction of CoastDat
• Validation of CoastDat
• Applications N Atlantic Polar Lows
• Applications pathway of gasoline lead
  pollution

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Downscaling cascade
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variance
global model
Insufficiently resolved
Well resolved
Spatial scales
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variance
regional model
Insufficiently resolved
Well resolved
Spatial scales
Added value
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Concept of Dynamical Downscaling
RCM
Physiographic detail
3-d vector of state
Known large scale state
projection of full state on large-scale scale
Large-scale (spectral) nudging
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Spectral nudging vs. standard formulation
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Extreme wind speeds over sea simulated and
recorded
simulated
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Interannual Variability of Storm Indices
Storm index Lund red - reconstruction, blue -
observations
(after Bärring and von Storch 2005)
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(No Transcript)
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Interannual Variability Water Levels
(Weisse and Plüß 2006)
Annual mean winter high waters Cuxhavenred
reconstruction, black observations
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20-yr running trends in SST at Helgoland (German
Bight)
(Meyer et al. 2009)
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• Applications
• a) Assessment of N European Storm Climate and
  related issues
• Pathway of gasoline lead pollution

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Climate simulations with CLM ( 50km) for Polar
Lows 1948-2007

• Driven by the NCEP reanalysis
• Spectral Nudging

Zahn, M., and H. von Storch, 2008 A longterm
climatology of North Atlantic Polar Lows.
Geophys. Res. Lett., 35, L22702,
doi10.1029/2008GL035769
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North Atlantic Polar Lows
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Flow and deposition of substances
Lead deposition in Europe

• Many anthropogenic substances released into the
  environment are transported over long distances
  and are deposited all over Europe and the rest of
  the world.
• Long term and spatially representative
  measurements unavailable. Alternative use of
  circulation and precipitation from long-term
  weather reconstruction to model fate of
  substances.

von Storch, H., M. Costa-Cabral, C. Hagner, F.
Feser, J. Pacyna, E. Pacyna, and S.Kolb, 2003
Four decades of gasoline lead emissions and
control policies in Europe A retrospective
assessment, The Science of the Total Environment
(STOTEN) 311, 151-176
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Lead deposition in Europe
1955
1965
Emissions
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Lead deposition in Europe
1995
Calculated depositionsof lead
deposition
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model estimate
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Lead deposition in Europe
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Weisse, R., H. von Storch, U. Callies, A.
Chrastansky, F. Feser, I. Grabemann, H. Günther,
A. Plüss, T. Stoye, J. Tellkamp, J.
Winterfeldt and K. Woth, 2009 Regional
meteo-marine reanalyses and climate change
projections Results for Northern Europe and
potentials for coastal and offshore
applications. Bull. Amer. Meteor. Soc., May 2009