Net regional trends in (black curves) ice thickness and (colored curves) front position, calculated from discharge-weighted individual glacier time series in the northwest (a), central east (b), central west (c), and southeast (d), with the colors corresponding to the locations mapped in the left plane. Negative values on the left y-axis indicate net cumulative retreat over the study period. Cumulative thickness changes are shown on the right y-axes, and are calculated from the mean of all regional glaciers and expressed as fractional changes from Ho. Lighter, dotted gray lines between the two starred points indicate linear interpolation between two sparse data points, and the apparent trend during this period should be treated with caution. Please note that the limits along the left y-axes vary between panels so that time series details are more visible.