Geostrophic wind shear from CFSR v2 data for usage in WAsP

The change of the geostrophic wind speed has an impact on boundary layer mixing that can be important for microscale flow modelling for wind energy purposes. The WAsP software is often used for this purpose. This dataset contains the climatological geostrophic wind shear and direction over the whole global on a 0.5 degree grid that has been used in WAsP 12. It was obtained from the 6-hourly CFSR v2 reanalysis for the period 2011 to 2017 (see https://doi.org/10.5065/D61C1TXF). The omni-directional geostrophic wind shear vector denotes how much the geostrophic wind speed is changing over a certain vertical distance. Because we are interested in geostrophic wind shear changes that contribute to turbulent mixing in the atmospheric boundary layer, it was estimated by using the data on pressure levels from the pressure level closest to the surface up to 500 hPa above that heights.More details about the implementation of the model in the WAsP software and a validation can be found in the corresponding technical report:Floors, R. R., Troen, I., & Kelly, M. C. (2018). Implementation of large-scale average geostrophic wind shear in WAsP12.1. DTU Wind Energy. DTU Wind Energy E No. 0169meandgdz_2010_2017_CFSRv3.nc: version with coordinate reference system in the coordinates for usage in GIS programs. NaN values at the poles are filled with 0.0, i.e. assuming barotropic atmosphere, which avoids crashes in the pywasp code. A single sector variable has been added, indicating that these values are valid for all wind direction, as opposed to other files that have values for each wind direction sector (for example: https://data.dtu.dk/articles/dataset/ERA5_atmospheric_stability_for_usage_in_WAsP_12_8/19576042). Naming conventions are in accordance with the windkit package (https://docs.wasp.dk/windkit/)

地转风速的变化对边界层混合产生重要影响，这对于风力能源的微尺度流动建模至关重要。WAsP软件常被用于此目的。本数据集包含了全球范围内以0.5度网格划分的气候学地转风切变和风向，这些数据曾在WAsP 12中使用。数据来源于2011至2017年期间每6小时的CFSR v2再分析（见https://doi.org/10.5065/D61C1TXF）。全向地转风切变矢量表明地转风速在一定垂直距离上的变化程度。鉴于我们关注对大气边界层湍流混合有贡献的地转风切变变化，该变化是通过从接近地表的气压层至500 hPa以上的气压层的数据来估算的。关于在WAsP软件中模型实现的详细情况及其验证，可参考相应的技术报告：Floors, R. R., Troen, I., & Kelly, M. C. (2018). WAsP12.1中大规模平均地转风切变的实现。DTU Wind Energy. DTU Wind Energy E No. 0169meandgdz_2010_2017_CFSRv3.nc：带有坐标参考系统坐标的版本，适用于GIS程序的使用。极地处的NaN值被0.0填充，即假设为等压大气，这避免了pywasp代码中的崩溃。增加了一个单一扇区变量，表明这些值适用于所有风向，与其他文件（例如：https://data.dtu.dk/articles/dataset/ERA5_atmospheric_stability_for_usage_in_WAsP_12_8/19576042）中每个风向扇区具有不同值的情况不同。命名规范遵循windkit包（https://docs.wasp.dk/windkit/）的规定。