Articles | Volume 16, issue 6
https://doi.org/10.5194/tc-16-2421-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-16-2421-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
23 Jun 2022
Research article |
| 23 Jun 2022
| 23 Jun 2022
Controls on Greenland moulin geometry and evolution from the Moulin Shape model
Lauren C. Andrews
CORRESPONDING AUTHOR
Global Modeling and Assimilation Office, NASA Goddard Space Flight
Center, Greenbelt, MD 20771, USA
Kristin Poinar
Department of Geology, University at Buffalo, Buffalo, NY 14260, USA
Research and Education in eNergy, Environment and Water (RENEW)
Institute, University at Buffalo, Buffalo, NY 14260, USA
Celia Trunz
Geosciences Department, University of Arkansas, Fayetteville, AR
72701, USA
Department of Applied Geomatics, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada
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Short summary
Short summary
This study addresses Greenland supraglacial lake drainages. We analyze ice deformation associated with lake drainages over 18 summers to assess whether
precursorstrain-rate events consistently precede lake drainages. We find that currently available remote sensing data products cannot resolve these events, and thus we cannot predict future lake drainages. Thus, future avenues for evaluating this hypothesis will require major field-based GPS or photogrammetry efforts.
Chad A. Greene, Alex S. Gardner, and Lauren C. Andrews
The Cryosphere, 14, 4365–4378, https://doi.org/10.5194/tc-14-4365-2020, https://doi.org/10.5194/tc-14-4365-2020, 2020
Short summary
Short summary
Seasonal variability is a fundamental characteristic of any Earth surface system, but we do not fully understand which of the world's glaciers speed up and slow down on an annual cycle. Such short-timescale accelerations may offer clues about how individual glaciers will respond to longer-term changes in climate, but understanding any behavior requires an ability to observe it. We describe how to use satellite image feature tracking to determine the magnitude and timing of seasonal ice dynamics.
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Short summary
We introduce a model for moulin geometry motivated by the wide range of sizes and shapes of explored moulins. Moulins comprise 10–14 % of the Greenland englacial–subglacial hydrologic system and act as time-varying water storage reservoirs. Moulin geometry can vary approximately 10 % daily and over 100 % seasonally. Moulin shape modulates the efficiency of the subglacial system that controls ice flow and should thus be included in hydrologic models.
We introduce a model for moulin geometry motivated by the wide range of sizes and shapes of...
