![]() This reflected signal is then received by the radar during its listening period. Note: it's a small fraction of the emitted energy that is scattered directly back toward the radar. If the energy strikes an object (rain drop, snowflake, hail, bug, bird, etc), the energy is scattered in all directions (blue). The radar emits a burst of energy (green in the animated image). Remote Sensing at Mace Head also benefits from involvement in Cloudnet European Research Infrastructure for the observation of Aerosol, Clouds, and Trace gases ACTRIS and ACTRIS-2 (grant agreement numbers 262209) European FP7 collaborative project BACCHUS (Impact of Biogenic versus Anthropogenic emissions on Clouds and Climate: towards a Holistic UnderStanding, grant agreement number 603445) and COST action ES1303: TOPROF (Towards operational ground based profiling with ceilometers, doppler lidars and microwave radiometers for improving weather forecasts) supported by COST (European Cooperation in Science and Technology).NEXRAD (Next Generation Radar) obtains weather information (precipitation and wind) based upon returned energy. The Remote Sensing Division of the Mace Head Atmospheric Research Station is run by the Centre for Climate & Air Pollution Studies ( C-CAPS) at NUI Galway and supported by Irish Environmental Protection Agency ( EPA), Irish Aviation Authority ( IAA), and Science Foundation Ireland ( SFI). The pictures shown here are updated every hour. ![]() LLJs are peaks in the profiles of horizontal wind speed retrieved from full conical scans (VAD) at 15 degrees elevation. Low level jet (LLJ) detection by Tuononen, et al. The WindCube is a scanning lidar and therefore does not only produce one vertical profile, but can also be used to monitor the horizontal distribution of aerosols and clouds. The lidar therefore is also suited for the detection of aerosol layers, like volcanic ash plumes. The wind measurements depend on the presence of scatterers in form of cloud droplets or aerosol particles. This may cause gaps in the plots, where quality screening removed invalid fit results. The goodness of the fit is influenced by clouds and wind velocity. The horizontal wind speed and the wind direction are derived using a least squares fit of the radial wind during full conical scans (VAD). Subsequently, the radial wind is converted into profiles of the three wind components. From the deviation of the detected wavelength from the emitted one, profiles of the radial wind can be determined. It emits at 1.54 µm and measures the intensity of backscattered light as well as the Doppler shift of the detected radiation. The Doppler lidar at Mace Head is a WindCube 200S (manufacturer Leosphere). Horizontal wind speed profiles and low level jets (LLJ). Tuononen from FMI (Finnish Meteorological Institute). Horizontal wind speed (at 15 degrees elevation) and height of low level jet. ![]() Algorithm to calculate EDR by Shu Yang from Icelandic Met Office and Reykjavik University. Logarithm of eddy dissipation rate (EDR) from VAD at 15 degrees elevation.ĭarker colours signify more turbulent conditions. Horizontal wind speed (colour) and direction(arrows). Vertical wind shear from horizontal wind direction (or wind veer) per 100 m altitude. Vertical wind shear from horizontal wind speed per 100 m altitude. Wind from direction: 0 and 360 degrees = North (wind coming from North). ![]() Positive = updrafts negative = downdrafts Vertical wind speed (radial wind at line-of-sight measurement pointing to zenith). Carrier-to-noise ratio (CNR) at line-of-sight measurement pointing to zenith.
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