reinhold steinackericam-map-20031 climatology of mesoscale alpine phenomena university of vienna...
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Reinhold Steinacker ICAM-MAP-2003 1
Climatology of Mesoscale Alpine Phenomena
University of Vienna Department of Meteorology
and Geophysics
Reinhold Steinacker, Christoph LotteranerDepartment of Meteorology and Geophysics
University of Vienna, Austria
• Motivation• VERACLIM• Some selected results• Conclusion
Reinhold Steinacker ICAM-MAP-2003 2
University of Vienna Department of Meteorology
and Geophysics
• Motivation:
Much of the conventional climatological work (long term climatographies) so far have been using 1D (time series analysis) and/or large scale/meso alpha scale3D/4D (space-time analysis; reanalysis)
Mesoscale climatographies were mostly restrictedto national or regional boundaries
Some of intense climate phenomena (extreme events especially over complex terrain) are on meso beta or even meso gamma scale!
Reinhold Steinacker ICAM-MAP-2003 3
University of Vienna Department of Meteorology
and Geophysics
Example: 3 National Weather Services (AT,CH.SI)monthly precipitation
CH
AT
SI
Reinhold Steinacker ICAM-MAP-2003 4
University of Vienna Department of Meteorology
and Geophysics
Example:Berliner WetterkarteMonthly mean sea level pressureDecember 2001Source: Met. Inst. FU Berlin
Reinhold Steinacker ICAM-MAP-2003 5
University of Vienna Department of Meteorology
and Geophysics
Example: ERA40; December 2001Monthly mean sea level pressure 850 hPaSource: ECMWF; www.ecmwf
Reinhold Steinacker ICAM-MAP-2003 6
University of Vienna Department of Meteorology
and Geophysics
• VERACLIM
A project sponsored by the Austrian Science Foundationto create a mesoscale (meso beta; 20, 10 km horiz. res.) analysis of the Alpine Atmosphere for the last 30 years.Data: GTS-type, 3-hourlyMethod: Variational (spline), including downscaling and CQCPrimary variables: Theta, Theta-E, msl-pressure, sfc-windSecondary variables: precipitation, snow depth, cloud coverDerived variables: p-tendency, stream-lines, melting level, CCL,
(moisture-flux-) divergence, ...1 parameter: 30(yr)*365(d)*8(3-hr)~87.600 fields á 2.400/9600 GP→10**8/10**9 GP
Reinhold Steinacker ICAM-MAP-2003 15
University of Vienna Department of Meteorology
and Geophysics
Monatlicher Tagesgang des Luftdruckes nördlich, südlich und in den Alpen (bezogen auf ein Mittel von 1020 hPa)
1015
1016
1017
1018
1019
1020
1021
1022
1023
1 2 3 4 5 6 7 8 9 10 11 12 13
Monat
Lu
ftd
ruc
k [
hP
a]
GP(33-16) Süden GP(33-25) Zentralalpen GP(33-34) Norden
Reinhold Steinacker ICAM-MAP-2003 16
University of Vienna Department of Meteorology
and Geophysics
• Conclusion and outlook
Until a mesoscale reanalysis system (4D-VAR) becomes available on a scale, resolving the Alpine topography realistically, VERACLIM represents a good basis for establishing high resolution (concerning time and space) fields for climatological work
Besides gridded fields also quality controlled data (biases, gross errors) are being determined
Evaluation will concentrate upon short duration, mesoscale phenomena around the Alps
A „reanalysis“ will be carried out with the new 4D VERA system, which is in the pre-operational phase, including a multivariate approach
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