Ice dynamic réponse to distint surface lake drainage mechanism on the Greenland Ice Sheet
Ice dynamic response to distinct surface lake drainage mechanisms on the Greenland Ice Sheet
Marco Tedesco1*, Ian Willis2, Matthew Hoffman3, Alison Banwell2 and Patrick Alexander1
1) City College of New York, 160 Convent Ave. MR927, New York, NY 10031, USA
2) Scott Polar Research Institute, University of Cambridge, Cambridge, CB2 1ER, UK
3) Fluid Dynamics Group, Los Alamos National Laboratory, T-3, Mail Stop B216 Los Alamos, NM 87545, U.S.A.
Accurate projections of the contribution of the Greenland Ice Sheet to sea level rise require understanding of the links between ice sheet hydrology and ice dynamics, which is currently lacking. Here we show that magnitudes and patterns of meltwater induced acceleration and uplift are different for a supraglacial lake that drains slowly (> 24 h) and one draining rapidly (2 h). Drainage events are associated with the opening and enlargement of the subglacial system, with the fast drainage occurring by hydro-fracturing and the slow drainage by reactivation of an existing moulin, causing ice velocities to increase by respectively 1500 % and 450 % of pre-event speeds and uplift of up to 0.2 m and 0.1m respectively. After the large pulse of meltwater, which should result in a considerable enlargement of the subglacial drainage system, ice velocities do not decrease below pre-drainage values.
This is the abstract of our paper submitted to Nature Geoscience that is currently under review. The data used in our study can be downloaded by clicking on the links after the abstract.
GET THE DATA
Citation for the data:
M. Tedesco, I. Willis, M. Hoffman, A. Banwell and P. Alexander (2012) Supraglacial lakes depth time series of two lakes on West Greenland. CUNY Digital Media, New York, NY, U.S.A.
M. Tedesco, I. Willis, M. Hoffman, A. Banwell and P. Alexander (2012) dGPS measurements over West Greenland. CUNY Digital Media, New York, NY, U.S.A.Get the data.
Marco Tedesco1*, Ian Willis2, Matthew Hoffman3, Alison Banwell2 and Patrick Alexander1
1) City College of New York, 160 Convent Ave. MR927, New York, NY 10031, USA
2) Scott Polar Research Institute, University of Cambridge, Cambridge, CB2 1ER, UK
3) Fluid Dynamics Group, Los Alamos National Laboratory, T-3, Mail Stop B216 Los Alamos, NM 87545, U.S.A.
Accurate projections of the contribution of the Greenland Ice Sheet to sea level rise require understanding of the links between ice sheet hydrology and ice dynamics, which is currently lacking. Here we show that magnitudes and patterns of meltwater induced acceleration and uplift are different for a supraglacial lake that drains slowly (> 24 h) and one draining rapidly (2 h). Drainage events are associated with the opening and enlargement of the subglacial system, with the fast drainage occurring by hydro-fracturing and the slow drainage by reactivation of an existing moulin, causing ice velocities to increase by respectively 1500 % and 450 % of pre-event speeds and uplift of up to 0.2 m and 0.1m respectively. After the large pulse of meltwater, which should result in a considerable enlargement of the subglacial drainage system, ice velocities do not decrease below pre-drainage values.
This is the abstract of our paper submitted to Nature Geoscience that is currently under review. The data used in our study can be downloaded by clicking on the links after the abstract.
GET THE DATA
Citation for the data:
M. Tedesco, I. Willis, M. Hoffman, A. Banwell and P. Alexander (2012) Supraglacial lakes depth time series of two lakes on West Greenland. CUNY Digital Media, New York, NY, U.S.A.
M. Tedesco, I. Willis, M. Hoffman, A. Banwell and P. Alexander (2012) dGPS measurements over West Greenland. CUNY Digital Media, New York, NY, U.S.A.Get the data.