TY - JOUR
T1 - Diverse landscapes beneath Pine Island Glacier influence ice flow
AU - Bingham, Robert G.
AU - Vaughan, David G.
AU - King, Edward C.
AU - Davies, Damon
AU - Cornford, Stephen L.
AU - Smith, Andrew M.
AU - Arthern, Robert J.
AU - Brisbourne, Alex M.
AU - De Rydt, Jan
AU - Graham, Alastair G.C.
AU - Spagnolo, Matteo
AU - Marsh, Oliver J.
AU - Shean, David E.
PY - 2017/12/1
Y1 - 2017/12/1
N2 - The retreating Pine Island Glacier (PIG), West Antarctica, presently contributes 5-10% of global sea-level rise. PIG's retreat rate has increased in recent decades with associated thinning migrating upstream into tributaries feeding the main glacier trunk. To project future change requires modelling that includes robust parameterisation of basal traction, the resistance to ice flow at the bed. However, most ice-sheet models estimate basal traction from satellite-derived surface velocity, without a priori knowledge of the key processes from which it is derived, namely friction at the ice-bed interface and form drag, and the resistance to ice flow that arises as ice deforms to negotiate bed topography. Here, we present high-resolution maps, acquired using ice-penetrating radar, of the bed topography across parts of PIG. Contrary to lower-resolution data currently used for ice-sheet models, these data show a contrasting topography across the ice-bed interface. We show that these diverse subglacial landscapes have an impact on ice flow, and present a challenge for modelling ice-sheet evolution and projecting global sea-level rise from ice-sheet loss.
AB - The retreating Pine Island Glacier (PIG), West Antarctica, presently contributes 5-10% of global sea-level rise. PIG's retreat rate has increased in recent decades with associated thinning migrating upstream into tributaries feeding the main glacier trunk. To project future change requires modelling that includes robust parameterisation of basal traction, the resistance to ice flow at the bed. However, most ice-sheet models estimate basal traction from satellite-derived surface velocity, without a priori knowledge of the key processes from which it is derived, namely friction at the ice-bed interface and form drag, and the resistance to ice flow that arises as ice deforms to negotiate bed topography. Here, we present high-resolution maps, acquired using ice-penetrating radar, of the bed topography across parts of PIG. Contrary to lower-resolution data currently used for ice-sheet models, these data show a contrasting topography across the ice-bed interface. We show that these diverse subglacial landscapes have an impact on ice flow, and present a challenge for modelling ice-sheet evolution and projecting global sea-level rise from ice-sheet loss.
U2 - 10.1038/s41467-017-01597-y
DO - 10.1038/s41467-017-01597-y
M3 - Article
AN - SCOPUS:85034638063
SN - 2041-1723
VL - 8
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 1618
ER -