Adalgeirsdottir, A.

Hvidberg, C. S.

Simonsen, S. B.

Stenseng, Lars

Online Research Database In Technology

                       General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.  • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal   If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.     Downloaded from orbit.dtu.dk on: Dec 17, 2017Monte Carlo inversion of firn layers observed in firn cores and radar images - avalidation of a dynamic firn compaction modelSimonsen, S. B.; Stenseng, Lars; Adalgeirsdottir, A.; Hvidberg, C. S.Published in:Geophysical Research AbstractsPublication date:2012Document VersionPublisher's PDF, also known as Version of recordLink back to DTU OrbitCitation (APA):Simonsen, S. B., Stenseng, L., Adalgeirsdottir, A., & Hvidberg, C. S. (2012). Monte Carlo inversion of firn layersobserved in firn cores and radar images - a validation of a dynamic firn compaction model. GeophysicalResearch Abstracts, 14, [EGU2012-8675].Geophysical Research AbstractsVol. 14, EGU2012-8675, 2012EGU General Assembly 2012© Author(s) 2012Monte Carlo inversion of firn layers observed in firn cores and radarimages - a validation of a dynamic firn compaction modelS. B. Simonsen (1,2), L. Stenseng (3), G. Adalgeirsdottir (2), and C. S. Hvidberg (1)(1) Centre for Ice and Climate, Niels Bohr Institute, University of Copenhagen, Denmark (sbs@nbi.ku.dk), (2) DanishClimate Centre, Danish Metrological Institute, Denmark, (3) Geodesy Department, DTU Space, DenmarkRecent studies of ice sheet mass loss have shown the importance of understanding the firn compaction at thesurface. The ongoing mass changes of the Greenland Ice Sheet have been extracted by correcting altimetry datafrom the ICESat mission with a firn compaction model. The result shows that the changes in firn compaction overthe observation period are the most important correction factor when converting the measured volume change intomass change. However, little knowledge about the spatial variability of the applied parameterization is available.In this study, a simple empirical firn model that is forced with the output of high-resolution (5km) regionalclimate model (HIRHAM5) is applied. The model is inverted using a Monte Carlo method, in order to fit availableobservations from firn cores and internal layering seen by remote sensing radar measurements. The internallayering is observed using radar measurements penetrating the upper part of the firn column in the interior part ofGreenland. The observed layers from the radar data can be used as an in-situ validation of the firn model resolvinga large spatial coverage.The combination of observation from the firn cores and radar measurements gives the possibility to assess thebiases in the individual inversions performed to optimize the firn parameterization. This model validation givesa good confidence in using the model to address important questions. Questions such as; how large is the firncompaction correction relative to the changes in the elevation of the surface observed with remote sensingaltimetry? What model time resolution is necessary to resolve the observed layering? What model refinementsare necessary to give better estimates of the surface mass balance of the Greenland ice sheet from remote sensingaltimetry?

Monte Carlo inversion of firn layers observed in firn cores and radar images - a validation of a dynamic firn compaction model

http://orbit.dtu.dk/ws/files/87942963/EGU2012-8675.pdf

Monte Carlo inversion of firn layers observed in firn cores and radar images - a validation of a dynamic firn compaction model

Abstract

Similar works

Full text

Available Versions

Online Research Database In Technology