Frontal ablation estimates for 49 tidewater glaciers in Greenland

This dataset contains frontal ablation estimates for 49 tidewater glaciers in Greenland with the variables being defined as follows:

• F – Frontal ablation during time intervals [Gt/d]
• Max_Error_F – Maximum error over total time period [Gt/d]
• Date – Midpoint of time intervals on which output data defined [yyyy-mm-dd]
• D – Discharge during time intervals [Gt/d]
• TMC – Terminus mass change (dM/dt) during time intervals [Gt/d]

The frontal ablation estimates have been calculated using the following open-source remote sensing data:

1. TermPicks Terminus delineations (Goliber and Black, 2021).
2. Satellite image (for manual delineation of fjord walls).
3. Glacier velocity (code will automatically download ITS_LIVE velocities ~15 GB)
4. Two Digital Elevation Models (preferably ArcticDEM and AeroDEM; Porter et al., 2018, Korsgaard et al., 2016)
5. Surface change rate (Khan, 2017)
6. Bedrock Topography (BedMachine v4; Morlighem et al., 2017, 2021).
7. Solid Ice Discharge (Mankoff, 2019)

For completion, we also include data that are used to calculate terminus mass change (TMC) in the folder of the same name. Terminus mass change (dM/dt) is determined as the difference between subsequent observations (M(2)-M(1)….M(n+1)-M(n)). Each file contains the following variables: 

• Date – Data of terminus position [yyyy-mm-dd]
• A – Area of polygon [km2]
• H – mean ice thickness H [km] determined using ArcticDEM, AeroDEM and surface elevation change rates (see methods and Figure 6 in Fahrner et al., 2023).
• V – Volume of polygon [km3]
• M – Mass of polygon [km3] assuming constant ice density (rho = 0.917 kg/km3)

We also include the filtered, and extrapolated or clipped, TermPicks terminus positions that are used to determine the frontal ablation estimates in geopackage and shapefile format ("TerminusPositions" folder).

The processing chain to derive these frontal ablation estimates is described in Fahrner et al., (2023) and  can been found at https://zenodo.org/records/10278429 
 

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When using this data set please cite:

Fahrner, D., Slater, D., KC, A., Cenedese, C., Sutherland, D.A., Enderlin, E., de Jong, F., Kjeldsen, K.K., Wood, M., Nienow, P. Nowicki, S., Wagner, T. (2023): A Frontal Ablation Dataset for 49 Tidewater Glaciers in Greenland

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References

Goliber, S. and Black, T., (2021) TermPicks: A century of Greenland glacier terminus data for use inmachine learning applications. [online] Available at: https://zenodo.org/record/5117931 [Accessed 27 May 2022].

Khan, S.A., (2017) Greenland Ice Sheet Surface Elevation Change. Available at: http://promice.org/PromiceDataPortal/api/download/90fb4cbf-e88e-4e26-af95-a47d19a9cf10.

Korsgaard, N.J., Nuth, C., Khan, S.A., Kjeldsen, K.K., Bjørk, A.A., Schomacker, A. and Kjær, K.H., (2016) Digital elevation model and orthophotographs of Greenland based on aerial photographs from 1978–1987. Scientific Data, [online] 31, p.160032. Available at: https://doi.org/10.1038/sdata.2016.32.

Mankoff, K.D., (2019) Ice dicharge for the Greenland ice sheet. Available at: https://doi.org/10.22008/PROMICE/DATA/ICE_DISCHARGE.

Morlighem, M., Williams, C., Rignot, E., An, L., Arndt, J.E., Bamber, J., Catania, G., Chauché, N., Dowdeswell, J.A., Dorschel, B., Fenty, I., Hogan, K., Howat, I., Hubbard, A., Jakobsson, M., Jordan, T.M., Kjeldsen, K.K., Millan, R., Mayer, L., Mouginot, J., Noël, B., O'Cofaigh, C., Palmer, S.J., Rysgaard, S., Seroussi, H., Siegert, M.J., Slabon, P., Straneo, F., Broeke, M.R. van den, Weinrebe, W., Wood, M. and Zinglersen, K., (2021) IceBridge BedMachine Greenland, Version 4.

Morlighem, M., Williams, C.N., Rignot, E., An, L., Arndt, J.E., Bamber, J.L., Catania, G., Chauché, N., Dowdeswell, J.A., Dorschel, B. and others, (2017) BedMachine v3: Complete bed topography and ocean bathymetry mapping of Greenland from multibeam echo sounding combined with mass conservation. Geophysical research letters, 4421.

Porter, C., Morin, P., Howat, I., Noh, M.-J., Bates, B., Peterman, K., Keesey, S., Schlenk, M., Gardiner, J., Tomko, K., Willis, M., Kelleher, C., Cloutier, M., Husby, E., Foga, S., Nakamura, H., Platson, M., Wethington Jr., M., Williamson, C., Bauer, G., Enos, J., Arnold, G., Kramer, W., Becker, P., Doshi, A., D'Souza, C., Cummens, P., Laurier, F. and Bojesen, M.A.-N.S.F.A.-N.S.F., (2018) ArcticDEM. V1 ed. Available at: https://doi.org/10.7910/DVN/OHHUKH.