This folder contains the Matlab scripts that we used to get the results and plot the figures in our paper on methods to detect seasonal variability from feature tracking (Greene, Gardner, & Andrews, 2020). For some of these scripts you may need Antarctic Mapping Tools for Matlab (Greene, Gwyther, & Blankenship, 2017) or the Climate Data Toolbox for Matlab (Greene et al., 2019). Also be sure to check out my Github page (www.github.com/chadagreene) for tools specific to ITS_LIVE data. If you have any questions, you can always try emailing me at chad@chadagreene.com. 

File Descriptions: 
byrd_test_data.mat an ITS_LIVE velocity time series from an arbitrary 240x240 grid cell near the grounding line of Byrd Glacier, Antarctica. 

compute_seasonal_uncertainty.m calculates seasonal amplitude and phase uncertainty under many unique combinations of N image pairs, interannual variability, and seasonal variability. creates itslive_seasonal_unc.mat. 

image_pair_times.mat acquisition times and vx uncertainty values for all Antarctic ITS_LIVE image pairs as of Dec 2019. 

itslive_seasonal_A.mat median absolute deviations of amplitude and phase calculations for different unique values (un) of seasonal amplitude. 

itslive_seasonal_interannual.mat median absolute deviations of amplitude and phase calculations for different unique values of interannual variability. Several results here, for different amplitudes A. 

itslive_seasonal_iter.mat uncertainties as a function of iterations. 

itslive_seasonal_Npairs.mat uncertainties as a function of N image pairs. 

itslive_seasonal_parameter_tests.m runs the tests where parameters A, interannual, iter, Npairs, and phase are isolated. Saves the corresponding .mat files. 

itslive_seasonal_unc.m a function that estimates seasonal amplitude and phase uncertainty by interpolating the itslive_seasonal_unc.mat data (which was generated by compute_seasonal_uncertainty.m). 

itslive_seasonal_unc.mat Seasonal amplitude and phase uncertainty estimates from the distributions of errors calculated by compute_seasonal_uncertainty.m. This dataset is interpolated by the itslive_seasonal_unc.m function. 

make_fig*.m These files make each figure in the Cryosphere paper. 

point_ts_KAN_L.mat is the time series of available ITS_LIVE image pair data at a single grid cell on Russell Glacier (Greenland) near the PROMICE KAN_L GPS station. The data here are plotted by the make_fig07.m script. 

recovered_amp_phase_all_4.mat data generated by itslive_seasonal_parameter_tests.m and plotted by make_fig07.m. 

