Melting at Thwaites Grounding Zone and its Control on Sea Level

MELT is an ice-based project that will use autonomous sensors to monitor the ice column and ocean beneath the ice shelf in the critical area of the grounding line (the point where the glacier goes afloat to become ice shelf). The project will also use repeated airborne radar flights to study the way the ice flows in this area, and seismic surveys to study the ocean floor beneath the ice shelf.

Hot water drilling will be used to make three access holes through the glacier to allow measurements to be made within the ice column and in the underlying water. Icefin, a state-of-the-art remotely-operated vehicle containing instruments such as conductivity-temperature-depth (CTD) sensors, an acoustic Doppler current profiler, a camera, a dissolved oxygen sensor and a multi-beam echosounder will be deployed via the boreholes to examine the waters beneath the ice shelf. Ocean moorings will be used to monitor the ocean conditions for a year or more and ground-based phase-sensitive radar (ApRES) will monitor the basal melt rate.

At present, the influence of these warm waters is not well understood, especially in the key area of the grounding line, and quantifying how ocean conditions affect the melt rate of Thwaites Glacier’s ice shelf will allow the glacier’s potential sea-level contribution to be more accurately predicted.