Super Site Instrumentation Calendar

Eddy Covariance

Fall

• Swap out Licor 7200RS and ship to Nebraska for recalibration.
  • We have three units. I trade out the top one so the tower is always running and the subcanopy is off for part of the winter.

Winter / Spring / before leaf up

• The recalibration takes 4-8 weeks with shipping and purchase requests etc. So by the time the units are returned it is December. Aside from brief good weather windows it's pretty cold. So some year's we have been able to reinstall the sub canopy in December and other years it stretches into April/May due to travel schedule and climate of winter. The goal is to have both units operational by snowmelt in late April/ mid May.

Procedure

• Follow this link: Licor 7200 RS Swap

Air Temperature / Relative Humidity

• All sensors are sent away for recalibration once every two years. On a 4 & 4 schedule ideally.
  • But also, as sensors fail they are replaced and then the schedule is off. The 4x4 schedule is mostly for budget purposes rather than scientific reasons.
• Record keeping on AT/RH is probably the weakest.

Tower Wind Speed

• All sensors are sent away for recalibration once every two years. On a 5 & 4 schedule ideally.

Gill Windmaster Pro

• Sent out occasionally

PAR

• Every 8 years or so instruments replaced but new ones are colocated with old ones for a year or two.

CNR4 Net Radiation

• Sent out for recalibration every 2-3 years
• Check for level at the start of spring and in the fall

Snow Depth Sensor

• Campbell Scientific SR50A ultrasonic distance sensor
• Transducers replaced every 1-2 years
  • one by shed
  • one behind shed at second soil pit
  • one mounted to tower
  • one mounted at the forest floor radiation stand

Tipping bucket rain gage

• Checked for level in spring and again in summer.

Geonor Rain Gauge

• Check for level every month of summer using a Geonor branded torpedo level
• In fall (around October 1st ideally) drain the bucket of prior year of precipitation and refill with proper mixture of alcohol and antifreeze
  • I will add the amounts later but they are also on labeled equipment in the basement storage room 106.

Skin Temperature sensor

• Replace as they break (they seem to die occasionally). Can compare their signal to the upwelling longwave radiation data converted to temperature.