Data of two sites in Somalia underlying the paper: Multistability of model and real dryland ecosystems through spatial self-organization

For both sites, topographical data was retrieved from the ALOS World 3D 30m (AW3D30, v. 2.1) digital raster elevation model. This model describes the height above sea level (in m, rounded to the nearest integer), at a ground resolution of approximately 30m at the equator. The elevation data was preprocessed for the removal of artifacts by applying a global soft-thresholding on its dual tree complex wavelet transform. Specifically, we set a threshold of 0.9 on the first five dual-tree complex wavelet transform levels. From the preprocessed data, we calculated the slope gradient (in %) and slope aspect (in degrees). We first extracted square DEM windows of 33 by 33 cells (i.e. approximately 990m × 990m), centered on the image windows. We then applied a least squares fitting procedure of an unconstrained quadratic surface on the unweighted elevation values. This gave the following datasets.针对两个站点，地形数据均获取自ALOS全球30米数字栅格高程模型（ALOS World 3D 30m，简称AW3D30，版本2.1）。该模型记录了海拔高度（单位：米，四舍五入至整数），在赤道处的地面分辨率约为30米。为去除伪影，我们对该数据的双树复小波变换（dual tree complex wavelet transform）实施全局软阈值处理以完成预处理。具体而言，我们在前五级双树复小波变换层级设置了0.9的阈值。从预处理后的数据中，我们计算得到坡度（单位：%）与坡向（单位：°）。首先，我们提取以图像窗口为中心的33×33像元正方形数字高程模型（Digital Elevation Model, DEM）窗口，尺寸约为990米×990米；随后，对未加权高程值执行无约束二次曲面的最小二乘拟合流程，最终得到下述数据集。