Data used in 'Local Wind Regime Induced by Giant Linear Dunes: Comparison of ERA5-Land Reanalysis with Surface Measurements.'

<p>This repository contains the data used in:</p> <blockquote> <p>Gadal, C., Delorme, P., Narteau, C. et al. Local Wind Regime Induced by Giant Linear Dunes: Comparison of ERA5-Land Reanalysis with Surface Measurements. Boundary-Layer Meteorol 185, 309&ndash;332 (2022). <a href="https://doi.org/10.1007/s10546-022-00733-6">https://doi.org/10.1007/s10546-022-00733-6</a></p> </blockquote> <p>where wind data measured at 4 different places in and across the Namib Sand Sea are compared to the data from the ERA5/ERA5Land climate reanalyses.</p> <p>The use this data, one should first look at the GitHub repository <a href="https://github.com/Cgadal/GiantDunes">https://github.com/Cgadal/GiantDunes</a> and at the corresponding documentation <a href="https://cgadal.github.io/GiantDunes/">https://cgadal.github.io/GiantDunes/</a>. The description sometimes refers to scripts used in <a href="https://github.com/Cgadal/GiantDunes/tree/master/Processing">https://github.com/Cgadal/GiantDunes/tree/master/Processing</a>.</p> <p>The two folders &#39;raw_data&#39; and &#39;processed_data&#39; contain the input raw_data, and the output data after processing used to make the paper figures, respectively. In each of them, &#39;.npy&#39; files contain Python dictionaries with different variables in them. They can be loaded using the Python library <code>numpy</code> as <code>data = np.load(&#39;file.npy&#39;, allow_pickle=True).item()</code>; and the different keys (variables) can be printed with <code>data.keys()</code> or <code>data[station].keys()</code> if <code>data.keys()</code> return the different stations. Unless specified otherwise below, note that all variables are given in the International System of Units (SI), and wind direction is given anticlockwise, with the 0 being a wind blowing from the West to the East.</p> <ul> <li>raw_data: <ul> <li>DEM: contains the Digital Elevation Models of the two stations from the SRTM30, downloaded from here: https://dwtkns.com/srtm30m/</li> <li>ERA5: hourly data from the ER5 climate reanalysis, on surface (_BLH) and pressure levels (_levels). Downloaded from https://cds.climate.copernicus.eu/</li> <li>ERA5Land: hourly data from the ER5Land climate reanalysis Downloaded from https://cds.climate.copernicus.eu/</li> <li>KML_points: kml points of the measurement station. It can be opened directly in GoogleEarth.</li> <li>measured_wind_data: contains the measured in situ data. The windspeed is measured using Vector Instruments A100-LK cup anemometers, the wind direction using Vector Instruments W200-P wind vane and the time using Campbell Instruments CR10X and CR1000X dataloggers.<br> &nbsp;</li> </ul> </li> <li>processed_data: <ul> <li>&#39;Data_preprocessed.npy&#39;: preprocessed_data, output of 1_data_preprocessing_plot.py</li> <li>&#39;Data_DEM.npy&#39;: properties of the processed DEM, the output of 2_DEM_analysis_plot.py</li> <li>&#39;Data_calib_roughness.npy&#39;: data from the calibration of the hydrodynamic roughnesses, the output of 3_roughness_calibration_plot.py</li> <li>&#39;Data_final.npy&#39;: file containing all computed quantities</li> <li>&#39;time_series_hydro_coeffs.npy&#39;: file containing the time series of the calculated hydrodynamic coefficients by &#39;5_norun_hydro_coeff_time_series.npy&#39;.</li> </ul> </li> </ul> <p>&nbsp; &nbsp; &nbsp; Depending on the loaded data file, main dictionary keys can be:</p> <ul> <li>&#39;lat&#39;: latitude, in degree</li> <li>&#39;lon&#39;: longitude, in degree</li> <li>&#39;time&#39;: time vector, in datetime objects (https://docs.python.org/3/library/datetime.html)</li> <li>&#39;DEM&#39;: elevation data array in [m], with dimensions matching &#39;lat&#39; and &#39;lon&#39; vectors</li> <li>&#39;z_mes&#39;, &#39;z_insitu&#39;, &#39;z_ERA5LAND&#39;: height of the corresponding velocity</li> <li>&#39;direction&#39;: measured wind direction, in [degrees]</li> <li>&#39;velocity&#39;: measured wind velocity, in [m/s]</li> <li>&#39;orientaion&#39;: dune pattern orientation, [deg]</li> <li>&#39;wavelength&#39;: dune pattern wavelength, [km]</li> <li>&#39;z0_insitu&#39;: chosen hydrodynamic roughness for the considered station.</li> <li>&#39;U_insitu&#39;, &#39;Orientation_insitu&#39;: hourly averaged measured wind velocities and direction</li> <li>&#39;U_era&#39;, &#39;Orientation_era&#39;: hourly 10m wind data from the ERA5Land data set</li> <li>&#39;Boundary layer height&#39;, &#39;blh&#39;: boundary layer height from the hourly ERA5 dataset</li> <li>&#39;Pressure levels&#39;, &#39;levels&#39;: Pressure levels from the pressure levels ERA5 dataset</li> <li>&#39;Temperature&#39;, &#39;t&#39;: Temperature from the pressure levels ERA5 dataset</li> <li>&#39;Specific humidity&#39;, &#39;q&#39;: Specific humidity from the pressure levels ERA5 dataset</li> <li>&#39;Geopotential&#39;, &#39;z&#39;: Geopotential from the pressure levels ERA5 dataset</li> <li>&#39;Virtual_potential_temperature&#39;: Virtual potential temperature calculated from the pressure levels ERA5 dataset</li> <li>&#39;Potential_temperature&#39;: Potential temperature calculated from the pressure levels ERA5 dataset</li> <li>&#39;Density&#39;: Density calculated from the pressure levels ERA5 dataset</li> <li>&#39;height&#39;: Vertical coordinates calculated from the pressure levels ERA5 dataset</li> <li>&#39;theta_ground&#39;: Averaged virtual potential temperature within the ABL.</li> <li>&#39;delta_theta&#39;: Virtual potential temperature at the ABL.</li> <li>&#39;gradient_free_atm&#39;: Virtual potential temperature gradient in the FA.</li> <li>&#39;Froude&#39;: time series of the Froude number U/((delta_theta/theta_ground)*g*BLH)</li> <li>&#39;kH&#39;: time series of the number &#39;kH&#39;</li> <li>&#39;kLB&#39;: time series of the internal Froude number kU/N</li> </ul> <p>Other keys are not relevant and are stored for verification purposes. For more details, please contact Cyril Gadal (see authors), and look at the following GitHub repository: <a href="https://github.com/Cgadal/GiantDunes">https://github.com/Cgadal/GiantDunes</a>, where all the codes are present.<br> &nbsp;</p>