modeling a heavy rainfall case in north-east estonia, august 2003. influence of model resolution
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Modeling a heavy rainfall case in North-East Estonia, August 2003. Influence of model resolution. Andres Luhamaa University of Tartu 2005. Overview of the event. Precipitation amount: in one day 1.5 times more than monthly mean. - PowerPoint PPT PresentationTRANSCRIPT
Modeling a heavy rainfall case in North-East Estonia, August 2003.
Influence of model resolution.
Andres LuhamaaUniversity of Tartu
2005
Overview of the event
● Precipitation amount: in one day 1.5 times more than monthly mean.
● High precipitation rates measured only in one (Estonian station)
Radar observations, aug 05, 17.00 – aug06, 06.00
Forecasts
● EMHI – general storm warning for Gulf of Finland, nothing more.
● FMI 22km forecast estimates high precipitation at the northern coast of Estonia.
Modelling experiment
● Influence of model resolution – 22km, 11km, 5km, 3km
● HH and NHH– Reference HIRLAM and non-hydrostatic
● Different versions of STRACO cloud scheme
– HIRLAM 6.1.0 - STR1– 6.1.2 (last major updates) - STR2– Research version for high resolutions (<5km)
called straco031 - STR3
FMI 22km forecast 11km STR-1 simulation
HH 11km simulation NHH 11km simulation
STR-2
HH 5km simulation NHH 5km simulation
STR-1
HH STR-2 5km simulation
NHH STR-2 5km simulation
NHH STR-3 5km simulation
NHH STR-1
NHH STR-2
3-km simulations
NHH STR-3
Conclusions:
● Nothing better than 22km HH forecast could be achieved ;(
● Significant difference between NHH and HH precipitation amounts already at 11km resolution!
– Parameterization tuning for HH->NHH modeling?
– As difference is only in amounts, is NHH necessary at coarser resolutions?