Monday 24 October 2016

Automatic weather stations (AWS) of the Finnish Meteorological Institute (FMI)

Automatic weather stations (AWS) of the Finnish Meteorological Institute (FMI)

FMI has a range of station types such as AWS, Solar, Marine, Lightning, Air quality, Research, Radar, Precipitation, Magnetometer, Masts, ..., etc.

Automatic Weather Stations:

FMI runs 178 AWSs across Finland. They are characterized by data being sent back to HQ frequently (e.g. every 10 minutes) of a range of basic variables (see photo and table below).


Symbol Variable Instrument Number of stations
Ta Air temperature (1.5 m agl) Platinum resistance thermometer (Theodor Friedrichs Pt100) 190
Tg Grass temperature (5 cm agl) Platinum resistance thermometer (Theodor Friedrichs Pt100) 101
ClB Cloud base Ceilometer (Vaisala CT25K) 92
RH Relative humidity Hygrometer (Vaisala HMP45D) 199
p Air pressure (corrected to mean sea-level) Barometer (Vaisala PTB220) 138
R Rainfall intensity and amount Weighing raingauge (OTT Pluvio2) 106
RO Rain: yes/no? On/off sensor (Vaisala DRD11A) 45
SnD Snow depth Sonic ranging (Campbell SR50AH) 101
S Sunshine Sunshine duration 32
U, dd Wind speed and direction Acoustic 2D anemometer (e.g. Thies UA2D) 159
PW, VIS Present weather & visibility Vaisala FD12P 94

Solar Stations:

FMI runs 8 Solar stations across Finland (Helsinki, Vantaa, Jokioinen, Jyväskylä, Utö, Sodankylä, Sotkamo, Utsjoki). 
Symbol Variable Instrument
Sdown Global incoming/downwelling shortwave (solar) radiation Pyranometer (CM11 or CNR4)
Sup Reflected/upwelling/outgoing shortwave (solar) radiation Pyranometer (CM11 or CNR4)
Ldown Incoming/downwelling longwave (thermal) radiation Pyrgeometer (CGR4 or CNR4)
Lup Upwelling/outgoing longwave (thermal) radiation Pyrgeometer (CGR4 or CNR4)
Dir Direct normal-downwelling shortwave (solar) radiation Eppley NIP with sun tracker or SPN1
Diff Diffuse incoming/downwelling shortwave (solar) radiation Pyranometer (CM11) with shade ring or suntracker
UVB Downwelling/incoming Ultraviolet B radiation Radiometer (SL501A)
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