Long wavelength topography of Io and predicted isostatic topography resulting from spatial variation in Io's tidal heating

After deriving equations that describe the response of isostatic, long-wavelength topography to spatial variation of Io's tidal heating, we use these equations to plot this response as a function of tidal heat variation. We compare the possible range of topographic amplitude to the observed global shape of Io (after subtraction of its hydrostatic shape)., The dataset for Io limb topography used in White et al. (2014, JGR: Planets, 119(6)) has been provided courtesy of Peter Thomas. This topography is measured with respect to the reference ellipsoid of Io (Thomas et al., 1998, Icarus 135(1)).
Spherical harmonic degree 3 and 4 coefficients were generated with the method summarized in White et al. (2014), using smoothing parameter r = 3*10^7., , # Data from: Long wavelength topography of Io and predicted isostatic topography resulting from spatial variation in Io's tidal heating

[https://doi.org/10.5061/dryad.b8gtht7k6](https://doi.org/10.5061/dryad.b8gtht7k6)

We include Io limb profile topography and the spherical harmonic coefficients of topography in degrees 3 and 4. Then, we utilize our derived equations to demonstrate a model of topography as a function of variation in tidal heating for comparison.

## Description of the data and file structure

We include 2 datasets and one program script.

ThomasLimbP.txt contains Io limb profile topography, and is provided courtesy of Peter Thomas. The Galileo image used for each profile is listed in Table 1 of [White et al. (2014, *JGR: Planets 119*(6), pp. 1276-1301)](https://doi.org/10.1002/2013JE004591). All the profiles are included in the same file, where the first column is the longitude (°W), the second column is latitude (°N), and the third column is the topography in km with...