Monday, 9 July 2018

MIMO: Monitoring sub-shelf melt where ice meets ocean

Ice shelves – the floating extensions of ice sheets - play a crucial role in controlling the present-day mass loss of the Antarctic ice sheet. Basically, ice shelves act as a cork on a bottle and restrain the inland ice through what is known as buttressing. Ice-shelf change is particularly pronounced in West Antarctica in response to increased oceanic heat transport beneath its floating ice shelf and resulting feedbacks, but evidence from around Antarctica confirms that the effect is not geographically limited. Ice-shelf thinning causes an instantaneous acceleration and a retreat of the grounding-line (limit between the grounded ice sheet and the floating ice shelf), hence a rise in sea level, which has major consequences for society.

One difficulty in studying Antarctic ice shelves arises from their unsteady nature. The ice geometry is evolving rapidly (years), ice is being advected at speeds >1 km/yr whilst the ocean beneath is expected to respond at sub-annual scales. In addition, there are many reasons to expect that the spatial pattern of melt is complex, where sub-shelf melting is concentrated in weaker zones of ice shelves, such as longitudinal bottom channels. Only a few studies have been focused on the spatial pattern, which requires high-resolution interferometrically-determined ice flow velocities and surface elevation and changes herein. Their application therefore remains limited to specific ice shelves or ice shelf sections for a particular snapshot in time, which is not useful for wider mapping, monitoring and impact assessment, which will be addressed in MIMO.

More info on the project, on the MIMO tab.

Monday, 4 July 2016

Warmer winter?

It seems like a warmer winter this year, but probably not. The temperatures of the radar sensors are significantly higher than last year. However, my position has changed. I am now installed close to the grounding line, an area where surface melt is predominant, and I feel it as well!

The GPS station are still at the same position of last year. However they moved with the motion of the ice shelf. Almost 500 m in less than 600 days.

GPS CGEO: my current position is 70.3999S, 25.0289E. I moved 471.6803m in direction N248.4208E in 571.9167 days.

GPS CDS: my current position is 70.4062S, 24.9927E. I moved 445.1747m in direction N248.9637E in 572.2083 days.

Sunday, 17 January 2016

Hello: I am back in business, despite a small data gap :-)

GPS CDS: my current position is 70.4073S, 24.9939E. I moved 313.121m in direction N248.8688E in 403.7083 days.

GPS CGEO: my current position is 70.4011S, 25.0302E. I moved 331.5652m in direction N248.4636E in 403.4167 days.

Tuesday, 22 December 2015

GPS CDS: my current position is 70.4075S, 24.994E. I moved 290.8009m in direction N248.5887E in 377 days.

Friday, 6 November 2015

GPS CDS: my current position is 70.4078S, 24.9944E. I moved 254.29m in direction N248.5234E in 330.5 days.
GPS CGEO: my current position is 70.4016S, 25.0307E. I moved 273.8975m in direction N248.2835E in 330.5 days.

Monday, 31 August 2015

GPS CDS: my current position is 70.4082S, 24.9948E. I moved 204.8561m in direction N338.7133E in 264 days.

GPS CGEO: my current position is 70.402S, 25.0312E. I moved 218.6968m in direction N338.1188E in 264 days.

Monday, 6 July 2015

GPS CDS: my current position is 70.4085S, 24.9952E. I moved 162.3373m in direction N338.4979E in 208.5 days.

GPS CGEO: my current position is 70.4024S, 25.0316E. I moved 172.6809m in direction N338.1068E in 208.5 days.