Root Mean Square Difference between the nine ensemble member change anomalies of the seasonal mean near-surface (2m) temperature for the median for 2036 - 2065 relative to 1976-2005, for the MAM season, under the RCP 8.5 pathway

Root Mean Square Difference for seasonal (MAM) mean near-surface (2m) temperature (°C) change from the median 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 temperature averages, which are used to generate projections of seasonal 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.

本数据集表征南部非洲区域在典型浓度路径8.5（Representative Concentration Pathway 8.5，RCP8.5）情景下，相对于基准期（1976-2005年），2036-2065年MAM季节平均近地面（2米）温度变化中值投影的均方根差（Root Mean Square Difference，RMSD）。为生成该可视化图像，研究采用罗斯比中心区域气候模式（Rossby Centre regional model, RCA4）为9个粗分辨率全球环流模式（General Circulation Models, GCM）提供侧边界强迫，将其降尺度至0.44°×0.44°的更高空间分辨率。该模式模拟的日平均温度数据被用于生成季节温度变化的投影结果。本次投影采用的高排放情景（RCP8.5）预计到2100年时大气二氧化碳浓度将达到约950ppm。所计算得到的对应均方根差可展示模式模拟投影残差的不确定性范围，并能相对直观地呈现不同空间区域的投影不确定性高低分布特征。