Ice thickness distribution and hydrothermal structure of Elfenbeinbreen and Sveigbreen, eastern Spitsbergen, Svalbard

In recent decades, Svalbard glaciers have been widely radioecho sounded. The earliest extensive surveys of ice thickness were the airborne echo soundings carried out in the 1970s and 1980s (Macheret and Zhuravlev, 1982; Dowdeswell and others, 1984). These studies used low-accuracy radar and positioning systems and mostly consisted of a single profile along the centre line of each glacier. Subsequent radar campaigns, mostly ground-based but sometimes also airborne, used increasingly improved radar and positioning systems providing a wider coverage of the glacier surfaces by radar profiles. A complete summary of glaciers on Svalbard with readily available radio-echo sounded ice-thickness data can be found in Martín-Español and others (2015)

An assessment of forward and inverse GIA solutions for Antarctica

In this work we assess the most recent estimates of glacial isostatic adjustment (GIA) for Antarctica, including those from both forward and inverse methods. The assessment is based on a comparison of the estimated uplift rates with a set of elastic-corrected GPS vertical velocities. These have been observed from an extensive GPS network and computed using data over the period 2009-2014. We find systematic underestimations of the observed uplift rates in both inverse and forward methods over specific regions of Antarctica characterized by low mantle viscosities and thin lithosphere, such as the northern Antarctic Peninsula and the Amundsen Sea Embayment, where its recent ice discharge history is likely to be playing a role in current GIA. Uplift estimates for regions where many GIA models have traditionally placed their uplift maxima, such as the margins of Filchner-Ronne and Ross ice shelves, are found to be overestimated. GIA estimates show large variability over the interior of East Antarc tica which results in increased uncertainties on the ice-sheet mass balance derived from gravimetry methods

The land ice contribution to sea level during the satellite era

Poster at Regional Sea Level Changes and Coastal Impacts conference, New-York, 10-14 July 201

First results from an integrated approach for estimating GIA, land ice, hydrology and ocean mass trends within a complete coupled Earth system framework

Poster at Regional Sea Level Changes and Coastal Impacts conference, New-York, 10-14 July 201

Spatial and temporal Antarctic Ice Sheet mass trends, glacio-isostatic adjustment and surface processes from a joint inversion of satellite altimeter, gravity and GPS data

We present spatiotemporal mass balance trends for the Antarctic Ice Sheet from a statistical inversion of satellite altimetry, gravimetry, and elastic-corrected GPS data for the period 2003–2013. Our method simultaneously determines annual trends in ice dynamics, surface mass balance anomalies, and a time-invariant solution for glacio-isostatic adjustment while remaining largely independent of forward models. We establish that over the period 2003–2013, Antarctica has been losing mass at a rate of −84 ± 22 Gt yr−1, with a sustained negative mean trend of dynamic imbalance of −111 ± 13 Gt yr−1. West Antarctica is the largest contributor with −112 ± 10 Gt yr−1, mainly triggered by high thinning rates of glaciers draining into the Amundsen Sea Embayment. The Antarctic Peninsula has experienced a dramatic increase in mass loss in the last decade, with a mean rate of −28 ± 7 Gt yr−1 and significantly higher values for the most recent years following the destabilization of the Southern Antarctic Peninsula around 2010. The total mass loss is partly compensated by a significant mass gain of 56 ± 18 Gt yr−1 in East Antarctica due to a positive trend of surface mass balance anomalies