For more information about the Flux Tower and data, please, contact CANDAC/PEARL site manager Dr. Pierre Fogal
Data
Eureka Flux Tower data archive, NOAA PSL
Since 2007, a 10 m flux tower (FT) has been operated as a part of PEARL. The tower is erected approximately 250 m NNE of the East end of the Eureka runway. Geographical coordinates of the FT are 79.9955 N, 85.7716 W. It is equipped with a suite of instruments to measure surface-atmosphere exchanges of energy and momentum by means of eddy covariance micro-meteorological method (Grachev et al., 2018). The suite includes temperature sensors, a 3-cup anemometer and vane, sonic anemometers, precipitation sensors, barometers, radiometers, a soil probe, and a gas analyzer. The gas analyzer has been used to measure CO2 and H2O concentrations in ambient air for better understanding of the atmosphere-surface CO2 flux. In 2014 the instrument suite was complemented with a Paroscientific micro barometer mounted 1 m above the surface. The micro barometer measures the atmospheric surface pressure at a frequency of 50 Hz and a resolution of ~0.01 Pa to detect rapid pressure variations associated with the fast gravity wave oscillations which are common in the boundary layer during winter (Chimonas, 2002). The FT instrumentation specification is given in Table 1.
The FT began as a joint effort between the National Oceanic and Atmospheric Administration and CANDAC within the framework of activities of the International Arctic Systems for Observing the Atmosphere (IASOA) to enhance Arctic atmospheric research (Uttal et al., 2016).
Table 1. Eureka flux tower instrumentation.
| Instrument | Model | Measurement | Level (m) | Sampling rate |
| 3-cup sentry anemometer & vane | R.M. Young: 03001-L | wind speed & direction | 11.1 | 1 min |
| High precision pyranometers | Kipp & Zonen: CM22 | total shortwave irradiance, downwelling & upwelling | 11.1 | 1 min |
| Precision infrared radiometer | Eppley:PIR | total longwave irradiance, downwelling & upwelling | 11.1 | 1 min |
| Humidity and temperature meter | Vaisala: HMT337 | air temperature & relative humidity | 10.1; 6.1; 2.33 | 1 min |
| RTD temperature probe | Campbell Scientific: 43347 | air temperature | 9.75; 5.98; 2.33 | 3 Hz |
| Fine-wire thermocouple | Campbell Scientific: ASPTC-L | air temperature | 9.1; 6.1; 2.33 | 1 min |
| Sonic anemometer | Metek: uSonic-3 Scientific | u, v, & w wind velocity, virtual temperature | 7.54; 3.07 | 10 Hz |
| Gas analyzer | Licor: LI-7500 | CO2 & H2O concentration | 8.0 | 10 Hz |
| Ultrasonic snow depth sensor | Campbell Scientific: SR50-L100 | snow depth | 2.3 | 1 min |
| Barometer | Campbell Scientific: CS105 | atmospheric pressure | 2.0 | 1 min |
| Precision infrared thermocouple sensor | Campbell Scientific: IRTS-P | ground surface temperature | 3.2 | 1 min |
| Averaging soil thermocouple probe | Campbell Scientific: TCAV-L | ground temperature | −0.05 | 1 min |
| Soil heat flux plate | Campbell Scientific: HFT3-L | soil temperature gradient | −0.05 | 1 min |
| Thermistor string | MRC | active layer depth temperature | − 0.05 to − 1.2 | 1 min |
| Microbarometer | Paroscientific: 6000-16B | atmospheric pressure | 1.0 | 50 Hz |