a short demo …. vejvejr is an internetbased surveillance and forecasting system, developed by dmi...
Post on 19-Dec-2015
217 views
TRANSCRIPT
a short demo ….
VejVejr is an internetbased surveillance and forecasting system, developed by DMI and Vejdirektoratet.
VejVejr provides any tools needed to secure proper decisionmaking with regards to preventing slippery roads.
Contacts:
Pernille Arnsfelt Hansen DMI – [email protected]
Søren Brodersen DMI – [email protected]
Slippery roads when: • Road-temperature < 0• Rime - dewpoint is higher than road-temperature• Ice – moisty or wet roads• Precipitation
We need to know:
• Road-temperature – actual and forecasted• Humidity – dewpoint• Precipitation• Cloudcover• Road condition – wet, moisty, salinity, freezingpoint etc.
Actual time or historic mode
Road T > + 2
Road T < + 2 but above 0
Road T < 0
Road T < 0 and dewpoint higher(riming)
Worst status next 5 hours
Choose your local area…
Forecasts for each roadweatherstation
doubleclick!
Alarm status
Observations
T 2m
Road T
dewpoint
Forecast
Road T < 0 from 02.50 hoursDewpoint is higher – this means riming (hoar frost)
Road resistance – how wet is the road ?
Dry
Moist
Wet
Salty
Forecast of precipitation – time/type/intensityForecast of cloudcoverForecast of wind – direction/speed
To 24 hour forecast
24 hour forecast
Forecasted precipitation:SnowSnow and rain mixedRain
Area-forecast
Comments from meteorologist
Online radar data – 10 min intervals
Precipitationtype and intensity:RainRain and snow mixedSnow (or freezing rain)
Animation
Online satellitedata from MSG2 – 15 min interval
Cloudtype color-code:Dense clouds – Weak radiation, weak road-cooling.Scattered clouds – Periodic radiation, some road cooling.Cirrus – Thin clouds, some radiation, some road cooling.
Animation
Allows you to follow changes in cloudcover – to spot areas with either clear weather (and cooling/radiation) as well as clouds that provide little or no heat-insulation.
Help - explanation
Online help to all screen-images
Online Web-cams
Regional text-forecast
7 days text-forecast
Observations from roadweatherstations - graphics
Roadtemperature
Roadcondition
Precipitation
Salinity
Freezingpoint
Roadweather observations for your chosen area - text
Observations from specific roadweatherstation - text
Animation - your own choise of observed parameters
This function allows you to follow any weather development, for instance roads cooling or precipitation spreading.
All observations can be animated and color-coded as you like it…
Graphics – your own choise of visualisation
Wind forecast (for bridges mainly)
How does it work …?
INPUT: •Observations, from roadweatherstation.
•Meteorological stations
•Satellite data (clouds)
•Atmosphere condition from HIRLAM weather model.
…compute
OUTPUT:
Future road condition.
Numeric ROAD Numeric ROAD CONDITION modelCONDITION model
Model area and road weather station network
Exclusive forecast available for each road-station.
0,0
0,2
0,4
0,6
0,8
1,0
1,2
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Prognoselænge
Cel
siu
s
Verification 2006-2007 :
Mean ABSOLUTE error. Mean ABSOLUTE error.
0
10
20
30
40
50
60
70
80
90
100
< 1 1 - 2 > 2
Celsius
%
2005 / 2006
2006 / 2007
(Situations with road temperature between -3 and +3)
Distribution of the 3-Distribution of the 3-hour forecast error.hour forecast error.
Error in degrees Celcius
Thank you for your attention.Thank you for your attention.
If you have questions or things you would like further explained, please contact us anytime.
Pernille Arnsfelt Hansen, meteorologist, [email protected]
Søren Brodersen, senior meteorologist, [email protected]