Current Met Station Components

Updated June 2018

Datalogger: CR3000 Campbell Sci.
14 differential (28 single-ended) analog input channels. 4 switched excitation outputs. 2 continuous analog outputs. 6 control ports. 4 pulse counting channels. 4 megabytes data storage memory. Extended range of -40°C to +85°C.
Multiplexer: AM25T, Campbell Sci.
The AM25T sequentially connects up to 25 thermocouples to a differential analog input on a CR800, CR850, CR10X, CR1000, CR3000, CR5000, CR7, or CR9000X datalogger. A PRT attached to the multiplexer's grounding bar provides a temperature reference for the thermocouple measurements. The heat capacity of the grounding bar and an insulated aluminum cover reduce thermal gradients along the length of the multiplexer. Reducing the thermal gradients allow more accurate measurements.
Pyranometer (Global Solar Radiation): Kipp & Zonen CMP-6
Spectral range 310 to 2800 nm. Sensitivity 5 to 20 μV/W/m2. Response time 18 s. Zero offset A ± 15 W/m2. Zero offset B ± 4 W/m2. Directional error (up to 80° with 1000 W/m2 beam) ± 20 W/m2. Temperature dependence of sensitivity (-10 °C to +40 °C) ± 4 %. Operating temperature range -40 °C to +80 °C. Maximum solar irradiance 4000 W/m2. Field of view 180°.
Pyranometer/Pyrgeometer: Kipp & Zonen CNR-4
The CNR4 is a pyranometer and pyrgeometer pair that faces upward and a second pair that face downward. The pyranometers and pyrgeometers measure shortwave and long-wave infrared radiation, respectively. There is also an internal thermistor for temperature correction and a heater to prevent frost deposition. Spectral response: pyranometer 305 to 2800 nm, pyreometer 4.5 to 42 μm. Response time: < 18 s. Uncertainty in daily total: pyranometer < 5%, pyrgeometer < 10%. Operating temperature: -40° to 80° C.
Ultraviolet Pyranometer: Yankee Environmental Systems, Inc. UVA-1 and UVB-1
The UVB-1 and UVA-1 Pyranometers measure total irradiance from 280 to 320 nm and 320 to 400 nm, respectively. The instruments produce a high level 0-4 VDC output signal and are thermally stabilized for long term reference-grade measurements. Response time is approximately 100 ms.
Quantum Sensor (Photosynthetically Active Radiation): Li-Cor, Quantum. Model LI-190SB
Quantum measure photosynthetically active radiation (PAR) in μmol s-1 m-2. Specs: range 400-700nm wavelength. Sensitivity 8mA/1000 μmol s-1 m-2. Relative error less then ±10% for plant canopies or less then ±5% for growth chambers.
Underwater Quantum Sensor: Li-Cor Underwater Quantum. LI-192SB
Accurate measurement of PAR in Aquatic systems. Spec: Sensitivity 3mA/100mE s-1 m-2. Relative error less then ±5%. Temperature dependence ±0.15% per °C. Maximum pressure 800 psi.
Relative Humidity/Temperature: Vaisala HMP155A Temperature and Relative Humidity Probe
TEMPERATURE: Calibrated measuring range: -80 to +60°C. Accuracy at 20-60°C: ±(0.055 + 0.0057 × temperature)°C. Sensor type: Pt 100 RTD 1/3 class B IEC 751. RH: Measuring range: 0.8-100% RH. Accuracy at 15-25°C: ±1% (0 to 905), ±1.7% (90 to 100%). Response Time: 20 seconds (63% step change), 60 seconds (90% step change). Sensor type: HUMICAP®180R.
Wind Monitor: RM Young
Wind direction is determined by a potentiometer whose voltage is proportional to the direction of the vane. Range: 0° to 360° mechanical, 355° electrical (5° open). Starting Threshold: 1.1 m/s. Wind speed is determined by the frequency of a sine wave produced by a magnet on the propeller shaft. Range: 0-100 m/s, accuracy: ±0.3 m/s. There are currently two wind monitors at the same height for redundancy. Temperature range: -50°C to +50°C, assuming no rime.
Year-round Rain Gauge: Pluvio N Rain Gauge (OTT)
70.010.000B.E. (08.03.1995) Measures rainfall based on weighing principle.
Summer Rain Gauge: Texas Electronics, Inc. TE525(WS) (supplied by Campbell Scientific) Tipping Bucket Electric Rain Gauge
A complex spun collector funnel with a knife edge that diverts the water to a tipping bucket mechanism. For each tip a magnet causes an electronic pulse that is recorded. Each alternate tip occurs for each 0.01 inch of rainfall. Specs: Accuracy 1% at 2 inches/hr or less. Accurate Temperature Range: 0 - 37°C.
Snow Depth: Campbell Scientific SR50A Sonic Ranging Sensor
Snow depth is determined by sending an ultrasonic pulse to the surface and an electrostatic transducer that listens to the reflected echoes. Range: 0.5 - 10 meters, Accuracy: 0.4% of distance to target.
Thermocouples: Omega Engineering, Copper-Constantan wire
Range -200 to 350 °C. Limits of error: Standard wire 1.0°C or 0.75% above 0°C and 1.0°C or 1.5% below 0°C. Special wire 0.5°C or 0.4%.
Pressure Transducer: Druck , PDCR 930TI
5 psi: ± 0.5% F.S. Toolik lake depth.
Evaporation Pan: Novalynx 255-100
Evaporation gage measure water level in a standard U.S. Class A evaporation pan (size 25.4 cm H X 120.6 cm I.D.) and provides an output proportional to the level in the pan. Specs: 0-25 cm. Accuracy ±0.76mm.
Barometer: Campbell Scientific CS106 Barometric Pressure Sensor
Technical Description: Measures barometric pressure over 600 to 1060 mb range Accuracy is ±0.5 mb @ +20°C Manufactured by Vaisala, Inc.
Communication System (Radiotelemetry): Campbell Scientific
RF450 Radio transmitting to RF50 base station, and a direct Ethernet connection for redundancy.

Contact with any questions, comments, or requests regarding Toolik metstation data.

Toolik Field Station © 2012-2019
Institute of Arctic Biology
P.O. Box 757005, 1038 Toklat Way
Fairbanks, AK 99775-7005
tel: 907.474.5159, fax: 907.474.5513,
All images courtesy of Institute of Arctic Biology unless otherwise noted.
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