ALEX17 high-resolution, digital information of topography, surface and aerodynamic roughness of the experimental domain

The present dataset is part of the Alaiz Experiment-2017 (ALEX17). The information is divided into two groups based on their source. 1)Two raster-tpye geotif files containing the Digital Elevation and Digital Surface Models (DEM and DSM) data of the ALEX17 domain. The models were built by TRACASA ( https://tracasa.es/all-about-us/) which is a company part of the Navarra Government. The original dataset is cropped to fit the ALEX17 experimental domain with the following spatial coverage: 607700, 4720300 628010, 4738800 The datasets are generated through lidar airborne scans taken during years 2011 and 2012 and updated by photogrammetry with orthophotos of year 2014. The original lidar scans (2011-2012) have a density of 1pnt/m^2 . The raw data are then processed and converted to orthometric heights (from the original ellipsoidal heights ) and later projected into a 2x2m grid with spatial reference EPSG:25830. The conversion from ellipsoidal to orthometric height is carried out with the EGM2008_REDNAP model, generated by the Spanish Geographic National Institute available in: ftp://ftp.geodesia.ign.es/geoide/ 2)The second dataset is also a raster-type file which contains the approximate annual mean of aerodynamic roughness length in meters. The maps was created with two data sources: Visual estimation of the roughness length values & zones. The Corine Land Cover (CLC) 2006 data. 2.1) The visual estimations of roughness values w carried out with the use of both, orthophotos gathered from the National Geographic Institute of Spain (IGN) as well as site visits. These values were assigned to the Alaiz mountain region while the 2.2) CLC-derived roughness was set to the rest of the domain area. The orthophotos are obtained from the National Plan for Aerial Orthophotogrpy (PNOA) program (available at http://www.ign.es/ign/layoutIn/faimgsataerea.do ). These photos have a pixel size of 50cm and were taken in summer 2014. On the other hand, the Corine Land Cover (CLC) 2006 raster dataset have a 100 m grid size. These data are available at http://www.eea.europa.eu/data-and-maps/data/corine- land-cover-2006-raster-3 (g100_06.zip file). The roughness values were derived from the Land Cover data mostly based on the relation between CLC and the aerodynamic roughness length applied by the Finnish wind atlas (http://www.tuuliatlas.fi/modelling/mallinnus_3.html ). The final composed roughness raster map was built by interpolation (nearest-neighbor) of the two data sources onto a 10x10 meters grid . The map is also projected with the same spatial reference as the DEM/DSM data described above.

本数据集隶属于阿拉伊兹实验-2017（ALEX17）。信息依据来源分为两组。其一，包含两个栅格类型地理信息文件，其中包含阿拉伊兹实验域的数字高程模型（DEM）和数字表面模型（DSM）数据。该模型由纳瓦拉政府旗下的TRACASA公司（https://tracasa.es/all-about-us/）构建。原始数据集经过裁剪以适应ALEX17实验域，其空间覆盖范围为：607700，4720300至628010，4738800。这些数据集通过2011年和2012年期间进行的机载激光扫描生成，并利用2014年的正射影像进行摄影测量更新。原始激光扫描（2011-2012年）具有每平方米1点的密度。原始数据随后经过处理并转换为正形高（从原始椭球高转换而来），并最终投影至2x2米的网格，空间参考为EPSG:25830。椭球高至正形高的转换使用的是由西班牙地理国家研究院（IGN）生成的EGM2008_REDNAP模型，可在以下网址获取：ftp://ftp.geodesia.ign.es/geoide/。其二，第二组数据集同样为栅格类型文件，包含约每年平均的气动粗糙度长度（米）。该图利用两个数据源创建：粗糙度长度值及区域的视觉估计，以及科里内土地利用覆盖（CLC）2006数据。2.1）通过使用从西班牙国家地理研究所（IGN）收集的正射影像以及现场考察，进行了粗糙度值的视觉估计。这些值被分配给了阿拉伊兹山脉地区；2.2）CLC衍生的粗糙度值设定在域区的其余部分。正射影像来源于国家航空正射影像计划（PNOA）项目（可在http://www.ign.es/ign/layoutIn/faimgsataerea.do获取）。这些影像具有50厘米的像素大小，并于2014年夏季拍摄。另一方面，科里内土地利用覆盖（CLC）2006栅格数据集具有100米的网格大小。这些数据可在http://www.eea.europa.eu/data-and-maps/data/corine-land-cover-2006-raster-3（g100_06.zip文件）获取。粗糙度值主要基于CLC与芬兰风图应用的气动粗糙度长度之间的关系从土地覆盖数据中导出。最终组成的粗糙度栅格图通过两个数据源在10x10米网格上的插值（最近邻插值）构建而成。该图亦采用与上述DEM/DSM数据相同的空间参考。