Band area (left column) and band depth (right column) measurements and 1σ uncertainties for Umbriel’s 2.14 μm, 2.2 μm, 2.22 μm, and 2.24 μm bands, displayed as a function of subobserver longitude (measurements reported in Tables A2–A5). The solid blue lines show the mean area and depth measurements for each band, and the dashed orange lines show sinusoidal fits to the data. Gray-toned zones represent duplicated subobserver longitudes. We compared the fits provided by the mean and sinusoidal models using an F-test (results reported in Table 6). Several data points on the 2.22 μm and 2.24 μm band measurement plots are notably larger than the mean band area or depth values, suggesting that the constituents contributing to these bands might be concentrated in specific geologic features or regions on Umbriel’s surface. Spatially resolved spectra are required to further investigate this possibility.