008 |
|
150512n^^^^^^^^xx^||||^o^^^^^|||^u^eng^d |
245 |
00 |
|a The effect of more realistic forcings and boundary conditions on the modelled geometry and sensitivity of the Greenland ice-sheet |h [electronic resource] |y English. |
260 |
|
|a [S.l.] : |b European Geosciences Union, |c 2010-03-12. |
490 |
|
|a The Cryosphere Discussions, 4. |
506 |
|
|a Please contact the owning institution for licensing and permissions. It is the user's responsibility to ensure use does not violate any third party rights. |
520 |
3 |
|a Ice thickness and bedrock topography are essential boundary conditions for numerical
modelling of the evolution of the Greenland ice-sheet (GrIS). The datasets currently in
use by the majority of Greenland ice-sheet modelling studies are over two decades old
and based on data collected from the 1970s and 80s. We use a newer, high-resolution
Digital Elevation Model of the GrIS and new temperature and precipitation forcings
to drive the Glimmer ice-sheet model offline under steady state, present day climatic
conditions. Comparisons are made in terms of ice-sheet geometry between these
new datasets and older ones used in the EISMINT-3 exercise. We find that changing
to the newer bedrock and ice thickness makes the greatest difference to Greenland
ice volume and ice surface extent. When all boundary conditions and forcings are
simultaneously changed to the newer datasets the ice-sheet is 25% larger in volume
compared with observation and 11% larger than that modelled by EISMINT-3.
We performed a tuning exercise to improve the modelled present day ice-sheet. Several solutions were chosen in order to represent improvement in different aspects of the
Greenland ice-sheet geometry: ice thickness, ice volume and ice surface extent. We
applied these new setups of Glimmer to several future climate scenarios where atmospheric
CO2 concentration was elevated to 400, 560 and 1120 ppmv (compared with
280 ppmv in the control) using a fully coupled General Circulation Model. Collapse
of the ice-sheet was found to occur between 400 and 560 ppmv, a threshold substantially
lower than previously modelled using the standard EISMINT-3 setup. This work
highlights the need to assess carefully boundary conditions and forcings required by
ice-sheet models and the implications that these can have on predictions of ice-sheet
geometry under past and future climate scenarios. |
533 |
|
|a Electronic reproduction. |c Florida International University, |d 2015. |f (dpSobek) |n Mode of access: World Wide Web. |n System requirements: Internet connectivity; Web browser software. |
700 |
|
|a E.J. Stone |u BRIDGE, School of Geographical Sciences, University of Bristol, UK. |
700 |
|
|a D.J. Lunt |u BRIDGE, School of Geographical Sciences, University of Bristol, UK. |
700 |
|
|a I.C. Runt |u School of the Environment and Society, Swansea University, UK. |
700 |
|
|a E. Hanna |u Department of Geography, University of Sheffield, Sheffield, UK. |
852 |
|
|a dpSobek |c Sea Level Rise |
856 |
40 |
|u http://dpanther.fiu.edu/dpService/dpPurlService/purl/FI15042568/00001 |y Click here for full text |
992 |
04 |
|a http://dpanther.fiu.edu/sobek/content/FI/15/04/25/68/00001/FI15042568thm.jpg |