Andrew K. Melkonian

Outlet glacier response to the 2012 collapse of the Matusevich Ice Shelf, Severnaya Zemlya, Russian Arctic

The Matusevich Ice Shelf (MIS), located within the Severnaya Zemlya Archipelago in the Russian Arctic, rapidly broke apart between 10 August and 7 September 2012. We examine the response of the outlet glaciers that fed the MIS from local ice caps to the removal of the ice shelf. We use spaceborne laser altimetry and multiple optically derived digital elevation models to track ice surface elevation change rates (dh/dt) between 1984 and 2014. Glacier speeds are measured by pixel-tracking from optical and RADAR imagery between 2010 and 2014 and interferometric synthetic aperture radar in 1995 to compare precollapse and postcollapse velocities. We find that the three main outlet glaciers that fed the MIS are thinning an order of magnitude more rapidly than most of the rest of Severnaya Zemyla, based upon ICESat data from 2003 to 2009. Recent, 2012 to 2014 thinning rates are three to four times faster than the 30 year average thinning rate, calculated between 1984 and 2014. The springtime speeds of the largest outlet glacier (Issledovateley) have increased more than 200% at the terminus between April 2010 and April 2014. To date, changes in surface elevation (dh/dt) and velocity at the outlet glaciers near MIS are smaller than glacier responses to ice shelf collapse in Antarctica. It is possible that the MIS was already very weak prior to the 2012 collapse and unable to support back stress. Further observations are required to assess whether the thinning and nonmelt season glacier speeds are continuing to accelerate.

Stikine Icefield Mass Loss between 2000 and 2013/2014

We calculate thinning rates (

Ice loss rates at the Northern Patagonian Icefield derived using a decade of satellite remote sensing

\frac{dh}{dt}

Ice loss from the Southern Patagonian Ice Field, South America, between 2000 and 2012

) at the 5,800 km\textsuperscript{2} Stikine Icefield of southeast Alaska from stacked digital elevation models (DEMs) acquired between 2000 and 2013/2014, and glacier velocities between 1985 and 2014 from feature tracking on optical image pairs. We find a mass change rate of -3.3

InSAR and Optical Constraints on Fault Slip during the 2010–2011 New Zealand Earthquake Sequence

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Satellite-derived volume loss rates and glacier speeds for the Cordillera Darwin Icefield, Chile

1.1 Gt yr\textsuperscript{-1} between 2000 and 2014, equivalent to an area-averaged elevation change rate of -0.57

Modeling the evolution of the Juneau Icefield between 1971 and 2100 using the Parallel Ice Sheet Model (PISM)

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Satellite-derived volume loss rates and glacier speeds for the Juneau Icefield, Alaska

0.18 m w.e. yr\textsuperscript{-1}. In 2014, land-terminating glaciers are 50\% of the Stikine Icefields glaciated area and contribute -0.9

Recent changes in glacier velocities and thinning at Novaya Zemlya

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Ice loss from the Southern Patagonian Ice Field, South America, between 2000 and 2012: ICE LOSS IN PATAGONIA

0.4 Gt yr\textsuperscript{-1} of mass change (27\% of the total), while marine-terminating glaciers are only 30\% of the total glaciated area, but contribute -1.5