Airborne Topographic Mapper (ATM) Bathymetry Toolkit Note: This release is the archived version of the code that was used in the publication by Studinger et al., 2022 (https://doi.org/10.5194/tc-16-3649-2022). A GitHub repository with updates is available at: https://github.com/mstudinger/ATM-Bathymetry-Toolkit The Airborne Topographic Mapper (ATM) was a scanning lidar developed and used by NASA for observing the Earth’s topography for several scientific applications, foremost of which was the measurement of changing Arctic and Antarctic ice sheets, glaciers and sea ice. ATM measured topography to an accuracy of better than 5 centimeters by incorporating measurements from GPS (global positioning system) receivers and inertial navigation system (INS) attitude sensors. This collection of MATLAB® functions is for working with ATM laser altimetry data products in HDF5 waveform format as well as ATM’s Continuous Airborne Mapping by Optical Translator (CAMBOT) three-channel, natural color, red, green, and blue (RGB) digital images. The functions provide tools to geolocate laser footprints, identify supraglacial hydrological features such as lakes and channels and estimate their water depth from lidar data. The data products are freely available at the National Snow and Ice Data Center (NSIDC) at https://nsidc.org/data/icebridge and can also be downloaded from the NASA Earthdata portal at https://earthdata.nasa.gov/ The ILATMW1B waveform data is available at NSIDC: https://nsidc.org/data/ILNSAW1B/versions/1 (narrow swath) https://nsidc.org/data/ILATMW1B/versions/1 (wide swath) The CAMBOT Level 0 raw data and the much larger Level 1B geolocated and orthorectified CAMBOT data product are available here:https://nsidc.org/data/IOCAM0/https://nsidc.org/data/iocam1b The methods for estimating water depths of supraglacial lakes on the Greenland Ice Sheet are described in a publication by Studinger et al., 2022 (https://doi.org/10.5194/tc-16-3649-2022). See also: User guide for NASA's Airborne Topographic Mapper HDF5 Waveform Data: Products: https://doi.org/10.5281/zenodo.7246097 Collection of MATLAB® functions for working with ATM (Airborne Topographic Mapper, laser altimetry data products in HDF5 waveform format: https://github.com/mstudinger/ATM-waveform-tools NASA's Airborne Topographic Mapper (ATM) ground calibration data for waveform data products: https://doi.org/10.5281/zenodo.7225936