First, the citation:
Mukherjee, K., Menounos, B., Shea, J., Mortezapour, M., Ednie, M., & Demuth, M. (2022). Evaluation of surface mass-balance records using geodetic data and physically-based modelling, Place and Peyto glaciers, western Canada. Journal of Glaciology, 1-18. https://dx.doi.org/10.1017/jog.2022.83
Peyto Glacier in 2017 (photo: J. Shea)
Now, the summary:
Glacier mass balance observations are challenging to make, and even more challenging to maintain over long periods on shoestring budgets. The Government of Canada has made continuous observations of glacier mass change at two main sites in western Canada: Peyto Glacier (Canadian Rockies) and Place Glacier (Southern Coast Mountains) since 1965 - some of our co-authors have worked for decades to continue these observations. The records for these sites are invaluable for documenting long-term glacier change in the region, but they are also used to calibrate a wide range of models (mass balance, hydrology, weather/climate).
Our recent paper (led by Dr. Kriti Mukherjee) takes a closer look at the last 40 years of these records, and finds that (1) we can use geodetic mass change information (from air photos and LiDAR) to calibrate a mass balance model but we need to include ice dynamics if we want to model mass balance properly, and (2) there are some potential errors in the reported mass balances at each of the sites. Without the original field notebooks, it is difficult to pinpoint the exact source of the error, but we can flag certain periods in the records where the modelled and observed annual mass balances strongly disagree:
Place Glacier, 1987 - 1993
Peyto Glacier, 2001 - 2006
Caveat emptor, as they say!
Glaciological, modelled, and geodetic mass balances at Peyto and Place glaciers.