Title: NCAS manchester radar wind profiler 1290mhz alvaiade 2017 Author(s): Lead Author: Dr Emily Grace Norton email:emily.norton@ncas.ac.uk website: https://amf.ncas.ac.uk institution: university of Manchester organization: national centre for atmospheric science (ncas) telephone: +44(0) 1234 744640 co-author: Prof Geraint Vaughan email: Geraint.vaughan@ncas.ac.uk institution: university of Manchester organization: national centre for atmospheric science (ncas) co-author: Dr William Brown email: wbrown@ucar.edu Name(s) of the Lead author and any co-authors email:wbrown@ucar.edu institution: NCAR organization: UCAR website: https://stage.staff.cms.ucar.edu/users/wbrown telephone: 303-497-8774 1.0 Data Set Overview: Introduction or abstract Atmospheric flow in complex terrain has received increased attention in recent years because of its numerous applications, including air pollution, contaminant dispersion, aviation, Alpine warfare and wind energy harvesting. While past research has mainly focused on and improved upon weather prediction at the mesoscale (resolution on the order of km), wind energy and dispersion applications demand improved accuracy of predictions at the microscale (tens to hundreds of meters). To this end, ERANET+, a European Union (EU) funding instrument, has granted a consortium of EU scientists a megaproject to provide the wind energy sector with more detailed wind resource mapping capabilities. This is to be accomplished through the creation and publication of a New European Wind Atlas (NEWA) based on the development of improved models for wind energy physics and forecasting. Embedded in the ERANET+ project is a comprehensive field campaign dubbed "Perdigão" in 2016-17, which will collect a reference data set at unprecedented spatial resolutions, characterizing both the mean and turbulent wind fields in a natural setting. Augmenting the basic measurement and modelling capabilities of EU scientists with those from the US investigators will add considerable value to the ERANET+ project while allowing US investigators to pursue scientific endeavors of their choosing. Time period covered by the data: Physical location (including lat/lon/elev) of the measurement or platform: 39 42 7.1 N (39.7020), -7 42 4.1 W (-7.70113) Data source if applicable (e.g., for operational data include agency) Centre for enviromental analysis (CEDA) http://ceda.ac.uk/ Any web address references (i.e., additional documentation such as Project web site) https://www.eol.ucar.edu/field_projects/perdig%C3%A3o http://www.neweuropeanwindatlas.eu/News/Nyhed?id=0d52530e-8c2c-43be-bf0b-4db3da3811c4 2.0 Instrument Description: The boundary layer wind profiler is a ‘clear air’ pulsed UHF Doppler radar, used to remotely sense the wind speed and direction in the lower troposphere 24 hours a day, under all weather conditions. The radar consists of three panels to emit and receive three separate beams, each panel being an array of 64 collinear dipole antennas. The vertical beam from the central panel measures the vertical component of the wind. The two lateral panels situated at 90 degrees to the back and side of the central panel provide the two oblique beams, enabling full wind vectors to be calculated. The backscattered UHF radiation comes from two sources in the atmosphere. It is most sensitive to Rayleigh scattering from hygrometers but in the absence of precipitation Bragg scattering occurs from refractive index gradients in the clear air on a scale of ½ a radar wavelength. The refractive index variations are caused by changes in humidity, temperature and pressure but in the troposphere the main cause is humidity fluctuations. In addition to the wind speed and direction which are extremely useful for weather forecasting models the wind profiler provides other information to the user. For example the signal to noise ratio (SNR) profiles provide a valuable insight into the structure of the atmosphere such as the height of the convective boundary layer and residual layers. The spectral width of the clear air signal is also of interest as it provides an indication of the turbulence. It is generally stationed at one of two main sites MRU Cardington, near Bedford or at the MST radar site, near Aberystwyth. The wind profiler is mounted onto a trailer so it is easy to deploy to different locations and has been involved in numerous field campaigns around Europe, including COPS, COPE, CSIP, NAMBLEX, TORCH, and CAP. https://www.ncas.ac.uk/en/the-facility-amf/260-amf-main-category/amf-radar-wind-profiler/1099-radar-wind-prof-overview Table of specifications (i.e., accuracy, precision, frequency, resolution, etc.) Transmitter Frequency 1290 MHz Transmitter Bandwidth 10 MHz Beam Width 8.5° Peak Power 3500 W Aperture 4 m 2 Antenna gain 25 dBi Average power (low mode) 40 W Average power (high mode) 100 W Minimum height (low mode) 73 m (depends on pulse length) Maximum height (high mode) 8 km (depends on atmospheric conditions) Altitude resolution 75 m (low mode) to 375 m (high mode) Intrinsic wind speed accuracy < 1m/s Intrinsic wind direction accuracy < 5° Periodicity of profile computation 15 minutes standard Operational temperature -20 °C to 30 °C Operational relative humidity 5% to 95 % without condensation Resistance to wind 20 m/s (average) 40 m/s (gusts) Manufacturer & Model: Degreane Horizon degrewind pcl1300 3.0 Data Collection and Processing: The data was collected while the wind profiler was stationed at Availade next to the operation centre. A clutter screen was erected to reduce the ground clutter. This data was postprocessed and contains less gaps in the data than the real time processing. Description of data collection time, altitude, size_of_gate, latitude, longitude, eastward_wind, northward_wind, upward_air_velocity, wind_speed, wind_from_direction, signal_to_noise_ratio_of_beam_1, signal_to_noise_ratio_of_beam_2, signal_to_noise_ratio_of_beam_3 , signal_to_noise_ratio_minimum , spectral_width_of_beam_1 , spectral_width_of_beam_2 , spectral_width_of_beam_3 qc_flag_wind , qc_beam_1 , qc_beam_2 , qc_beam_3 , skew_1 , skew_2, skew_3 Description of derived parameters and processing techniques used The data was processed with the Degreane software written by Philipp Currier and was converted to netcdf files using IDL. 4.0 Data Format: Data file structure and file naming conventions (e.g., column delimited ASCII, NetCDF, GIF, JPEG, etc.) NetCDF Data format and layout (i.e., description of header/data records, sample records) List of parameters with units, sampling intervals, frequency, range Data version number and date Description of flags, codes used in the data, and definitions (i.e., good, questionable, missing, estimated, etc.) 5.0 Data Remarks: The data from the campaign is generally very good. There were a few problems with the wind profiler overheating at setup part of the campaign but this problem was resolved by refilling the gas in the air conditioning unit. Electromagnetic interference was a problem on a few days during the campaign when the electromagnetic interference persisted the winds can be wrong but on the whole these periods were not very frequent. The days that had interference were the 30/04/2018, 3/05/2017, 5/05/2017, 6/05/2017, 7/05/2017, 8/05/2017, 10/05/2017, 11/05/2017, 12/05/2017, 16/05/2017, 20/05/2017, 21/05/2017, 25/05/2017, Missing data periods Missing data between 30/04/2017 11:00 -14:00 01/05/2017 9:00 -10:15 and 12:00 - 15:00 10/05/2017 8:30-9:30 6/06/2017 20:30 - 23:59 7/06/2017 00:00 - 16:00 6.0 References: