Catalogue Severe Weather Catalogue Severe Weather Netherlands 1950- todayNetherlands 1950- today

and ERA-40and ERA-40

Geert GroenGeert Groen

ECMWF June 2005ECMWF June 2005

Who does not want to learn from the past….Who does not want to learn from the past….

GALE

Februari 1, 1953: Februari 1, 1953:

1836 people killed, 187000 cattle drowned.1836 people killed, 187000 cattle drowned.August 25, 1972 and Nov 6, 1990:Fogaccidents 23 dead, 42 injured

FOG

STORMTornado:Tornado:

August 23, 1950, Veluwe, 35900 cm treesAugust 23, 1950, Veluwe, 35900 cm trees

June 25, 1967, Chaam and Tricht, 11 deadJune 25, 1967, Chaam and Tricht, 11 dead

Aug 11, 1972, Ameland, campers, 4 deadAug 11, 1972, Ameland, campers, 4 dead

Oct 6, 1981, airplane F28 Moerdijk 17 deadOct 6, 1981, airplane F28 Moerdijk 17 dead

Aug 26, 1986, Slochteren and AppingedamAug 26, 1986, Slochteren and Appingedam

Aug 5, 1993, Burgum (Gr), campingAug 5, 1993, Burgum (Gr), campingWinterproblems

Snow and Freezing precipitation:Snow and Freezing precipitation:

1958, 1963, 1969, 1978, 1981, 2002,….1958, 1963, 1969, 1978, 1981, 2002,….

My presentation:My presentation:BackgroundBackgroundObjectivesObjectivesExamplesExamplesExperience with ERA40Experience with ERA40PlansPlans

Background for this project: Background for this project:

Severe Weather leads to Weather Alarm, 3-5 Severe Weather leads to Weather Alarm, 3-5 cases/year...slow growing experiencecases/year...slow growing experience

Solution: look back in history….the catalogueSolution: look back in history….the catalogue

Disaster 1953, excellent reanalysis ECMWF/NCEPDisaster 1953, excellent reanalysis ECMWF/NCEP

Inspired to use ERA-40, 4D-reanalysis up to 6 days Inspired to use ERA-40, 4D-reanalysis up to 6 days before event before event

Objectives:Objectives:

Increasing knowledge Increasing knowledge

on a synoptic scale on a synoptic scale

of severe weatherof severe weather

Open all information (incl. ERA)Open all information (incl. ERA) Increase (my) experienceIncrease (my) experience Improve modelImprove model Operational knowledgeOperational knowledge Simulate severe weather eventsSimulate severe weather events Stimulate (E-)learningStimulate (E-)learning

Index exampleIndex example

Case-link exampleCase-link example

Typical chart-displayTypical chart-display

Experiences sofar:Experiences sofar:

PositivePositive Exploring ERA and historical material good Exploring ERA and historical material good

combinationcombination Inspired use of operational knowledgeInspired use of operational knowledge ERA: good pressure reconstructionERA: good pressure reconstruction ERA: thetaw mirror of fronts/troughsERA: thetaw mirror of fronts/troughs ERA: PV315K illustrativeERA: PV315K illustrative In general: ERA OK for large-scaleIn general: ERA OK for large-scale

Experiences sofar:Experiences sofar:

NegativeNegative ERA-resolution 6 hrs, 1.5 deg for ERA-resolution 6 hrs, 1.5 deg for

smaller scale eventssmaller scale events Windspeed 1-3 Bft to lowWindspeed 1-3 Bft to low No profiles and precipitationNo profiles and precipitation

Plans and wishes…….Plans and wishes…….

More cases (upto 10 cases/year?)More cases (upto 10 cases/year?) Good historical material Good historical material

Investigating by keyparametersInvestigating by keyparameters E-learning modulesE-learning modules Weather-simulatorWeather-simulator

Use of ECMWF and HIRLAM-forecastUse of ECMWF and HIRLAM-forecast Reanalysis of cases in HIRLAMReanalysis of cases in HIRLAM

Suggestions, questions and remarks?Suggestions, questions and remarks? Demonstration part of the test-Demonstration part of the test-

catalogue (7 dec 1959)catalogue (7 dec 1959)