Annual total rainfall (mm per year) change from the 10% percentile, projected for 2036 - 2065 relative to the present (1976-2005) under the of the RCP 8.5 pathway conditions.

Annual total rainfall (mm per year) change from the 10% percentile projected for 2036-2065, relative to present (1976 - 2005), under the RCP 8.5 pathway for the southern African region. To generate the image, nine coarse General Circulation Models (GCM) are downscaled to a finer spatial resolution (0.44°x 0.44°) using the Rossby Centre regional model (RCA4) forcing its lateral boundaries. The model simulated daily rainfall averages, which are used to generate projections of annual change. The projections are generated using the high (RCP8.5) pathway which associates CO2 concentrations of approximately 950ppm by the year 2100. The associated RMSD it calculated and shows the uncertainty range of the projected model simulated residual values, and gives a relative perspective of spatial areas associated with higher and lower projection uncertainties.

本数据集呈现南部非洲区域在典型浓度路径8.5（RCP 8.5）情景下，2036-2065年预估年总降雨量（单位：毫米/年）的第10百分位投影结果相较于基准期（1976-2005年）的变化量。为生成该可视化图像，研究人员通过强迫罗斯比中心区域气候模式（Rossby Centre regional model, RCA4）的侧边界条件，将9套粗分辨率全球环流模式（General Circulation Models, GCM）的模拟结果降尺度至0.44°×0.44°的更高空间分辨率。该模式模拟的日降雨量均值被用于生成年际降雨量变化的预估结果。本次预估采用高排放情景（RCP8.5）构建，该情景预计至2100年时大气二氧化碳浓度将达到约950ppm。研究同时计算了对应的均方根误差（Root Mean Square Deviation, RMSD），该指标可展示模式模拟预估残差的不确定性范围，并能相对呈现不同空间区域的预估不确定性高低分布情况。