SWL:Suwa Lake Site
view of Suwa lake
General site detail (Updated 25 February 2019)
 Site name
 Suwa Lake Site
 AsiaFlux site code
 Location Suwa City, Nagano Pref, Japan
 Position 36º 02' 47.62"N, 138º 06' 30.19"E
 Elevation 759 m above sea level
 Slope 0 deg
 Terrain type
 Area 1330 ha
 Fetch 3500 to 4500 for the dominant wind direction
 Climate Subarctic humid climate (Dfc)
 Mean annual air temperature
 Mean annual precipitation
 Vegetation type
 Domestic species (Overstory)
 Dominant species (Understory)
 Canopy height
 Age -
 LAI -
 Soil type

Eddy Covariance method (CO2)
 System Open-path systems (sensible heat, latent heat, CO2 flux)
 Wind speed 
 Three-dimensional sonic anemothermometer
 (CSAT3, Campbell)
 Air temperature
 Three-dimensional sonic anemothermometer
 (CSAT3, Campbell)
 Water vapor
 Open-path CO2/H2O analyzers (EC150, Campbell) 
 CO2 Open-path CO2/H2O analyzers (EC150, Campbell)
 Measurement height
 Approx.3m depending on the water level
 Sampling frequency
 10 Hz
 Averaging time
 30 min
 Data logger
 CR3000 (Campbell)
 Data storage
 CF card
 Original data

 Observation items
  Levels/ Depth
 Global solar radiation(incoming)
 3 m
 CNR4 (Kipp & Zonen)
 Global solar 
radiation (outgoing)
 3 m
 CNR4 (Kipp & Zonen)
 Long-wave radiation(incoming) 
 3 m
 CNR4 (Kipp & Zonen)
  Long-wave radiation(outgoing) 3 m
 CNR4 (Kipp & Zonen)
 Net radiation
 PPFD (incoming)
 PPFD (outgoing)
 Direct / diffuse radiation

 Direct / diffuse PPFD
 Air temperature
 3 m HMP60 (Vaisala)
 Humidity 3 m HMP60 (Vaisala)
 Soil temperature
 0.25, 0.5, 1 m 107 (Campbell)
 Soil heat flux
 Soil water 
 Wind speed
 Wind direction
 1 m
 CS106 (Campbell)
 Precipitation -

Observation Period and data Availability
 Measurement Period
 April 2015 to present
 Measurement Frequency
 Data Availability
 2015 in AsiaFlux Database
 Hiroki Iwata (hiwata [at] shinshu-u.ac.jp)
 Department of Environmental Sciences, Faculty of Science,
 Shinshu University
 3-1-1 Asahi, Matsumoto, Nagano 390-8621  JAPAN
 Tel : +81-263-37-2502
 Calibration Information

 Mast, Electrical power(AC)