Supplementary animations supporting "South-east Greenland Ice Sheet short term response to environmental conditions"

Animation S1: Animation showing MODIS imagery and edge detection for Kangerdlugssuaq glacier. Left hand plot shows band 1 surface reflectance of Kangerdlugssuaq and the surrounding area for each cloud free day, which forms a single frame of the animation; axis units are km. Central top figure shows surface reflectance of the 'active region', the area within which edge detection takes place; axis units are km. Second central figure down shows detected edge pixels (white) over the active region using the Sobel method; axis units are km. Third central figure down shows frequency of detected edge pixels (y-axis) using the Sobel method along the length of the glacier (x-axis, km). High frequencies signify likely calving margin positions. Central bottom figure shows gradient (y-axis) of across-glacier averaged surface reflectance along the length of the glacier (x-axis, km), used as part of the brightness profiling method of calculating margin position. High brightness gradient locations signify likely calving margin locations. Right hand plot shows detected margin positions after consolidation of the two detection methods and noise removal procedures; x-axis is relative margin position in km, y-axis is time in years beginning. A horizontal line travels down the plot to signify animation location within time.
Animation S2: Plots are the same as in Supplementary Animation S1, but for Helheim Glacier. Plot details are described in the caption for S1.

动画S1：展示康格尔隆萨克冰川（Kangerdlugssuaq Glacier）的MODIS影像与边缘检测过程的动画。左侧绘图面板展示该冰川及周边区域在每个无云日的第1波段地表反射率，该内容构成动画的单帧画面；坐标轴单位为千米（km）。中上方面板展示"活跃区域"（即开展边缘检测的区域）的地表反射率；坐标轴单位为千米（km）。中部偏下的第二幅绘图面板展示了采用索贝尔算子法（Sobel method）在活跃区域内检测到的边缘像素（白色）；坐标轴单位为千米（km）。中部偏下的第三幅绘图面板展示了沿冰川长度方向（横轴，单位：km）采用索贝尔算子法检测到的边缘像素出现频率（纵轴），频率较高的位置即为潜在的冰崩冰缘位置。底部中央面板展示了沿冰川长度方向（横轴，单位：km）的跨冰川平均地表反射率梯度（纵轴），该指标是计算冰缘位置的亮度剖面法的组成部分；亮度梯度较高的位置即为潜在的冰崩冰缘位置。右侧绘图面板展示了经两种检测方法融合与去噪流程处理后得到的冰缘检测位置；横轴为相对冰缘位置（单位：km），纵轴为起始年份的时间。一条水平线沿绘图面板向下延伸，用以指示动画在时间维度上的当前位置。
动画S2：绘图面板的设置与补充动画S1完全一致，仅针对黑尔海姆冰川（Helheim Glacier）开展分析。绘图细节可参考S1的图注说明。