AUTHOR=Gopalan Giri , Hrafnkelsson Birgir , Aðalgeirsdóttir Guðfinna , Pálsson Finnur 

TITLE=Bayesian Inference of Ice Softness and Basal Sliding Parameters at Langjökull

JOURNAL=Frontiers in Earth Science

VOLUME=Volume 9 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/earth-science/articles/10.3389/feart.2021.610069

DOI=10.3389/feart.2021.610069

ISSN=2296-6463

ABSTRACT=We develop Bayesian statistical models that are designed for the inference of ice softness and basal sliding parameters, important glaciological quantities. These models are applied to Langj\"{o}kull, the second largest temperate ice cap in Iceland at about 900 squared kilometers in area. The models make use of a relationship between physical parameters and ice velocity as stipulated by a shallow ice approximation that is generally applicable to Langj\"{o}kull. The posterior distribution for ice softness concentrates around $18.2 \times10^{-25} s^{-1}Pa^{-3}$; moreover, spatially varying basal sliding parameters are inferred allowing for the decomposition of velocity into a deformation component and a sliding component, with spatial variation consistent with previous studies. Bayesian computation is conducted with a Gibbs sampling approach. The paper serves as an example of statistical inference for ice softness and basal sliding parameters at temperate, shallow glaciers using surface velocity data.