50-m instrumented tower

The 50-m instrumented tower is being operated at NARL since 2009. It hosts both fast sensors (Sonic anemometer – RM Young (81000) and IR hygrometer – Li-COR) at two levels (4 m and 8 m) and slow sensors for meteorological parameters (temperature, relative humidity, wind speed and direction) at 6 levels (2, 4, 8, 16, 32 and 50 m). The pressure and incoming shortwave and longwave radiation are measured at 1.2 m altitude. The radiation sensors, soil temperature and moisture profile probes and a tipping bucket rain gauge were installed 20 m away from the tower towards south to minimize shadow effects. The sensible and latent heat fluxes are estimated using eddy covariance technique employing 20 Hz-resolution measurements from the ultrasonic anemometer and IR hygrometer. The fluxes along with radiation and sub-surface measurements provide an opportunity to study the energy balance in a variety of atmospheric conditions.