Brief communication: A submarine wall protecting the Amundsen Sea intensifies melting of neighboring ice shelves

Özgür Gürses,Christian Bernd Rodehacke,Qiang Wang,Vanessa Kolatschek

doi:10.5194/tc-13-2317-2019

Abstract

Abstract. Disintegration of ice shelves in the Amundsen Sea, in front of the West Antarctic Ice Sheet, has the potential to cause sea level rise by inducing an acceleration of ice discharge from upstream grounded ice. Moore et al. (2018) proposed that using a submarine wall to block the penetration of warm water into the subsurface cavities of these ice shelves could reduce this risk. We use a global sea ice–ocean model to show that a wall shielding the Amundsen Sea below 350 m depth successfully suppresses the inflow of warm water and reduces ice shelf melting. However, these warm water masses get redirected towards neighboring ice shelves, which reduces the net effectiveness of the wall. The ice loss is reduced by 10 %, integrated over the entire Antarctic continent.

Highlights

One of the consequences of the warming of Earth’s climate is sea level rise (Vaughan et al, 2013)
In Antarctica, remotely sensed, modeled and paleoclimatological proxy data indicate that the highest potential sea level contribution will come from the West Antarctic Ice Sheet (Bamber et al, 2009; Golledge et al, 2013; Joughin and Alley, 2011; Pollard and DeConto, 2009; Sutter et al, 2016), from the Amundsen Sea sector, where the progressive thinning of its ice shelves over the last 2.5 decades has greatly enhanced rates of ice mass loss emanating from this sector (Pritchard et al, 2012; Rignot et al, 2014; Shepherd et al, 2018)
Gürses et al.: A wall in the Amundsen Sea intensifies melting of nearby ice shelves fringing this sector of Antarctica – have been directly linked to changes in large-scale oceanic and atmospheric circulation, including the influence of El Niño–Southern Oscillation (ENSO)-induced atmospheric wave trains propagating towards this region from the central tropical Pacific Ocean (Dutrieux et al, 2014; Jenkins et al, 2018; Nakayama et al, 2018; Steig et al, 2012)

Summary

Introduction

One of the consequences of the warming of Earth’s climate is sea level rise (Vaughan et al, 2013). Gürses et al.: A wall in the Amundsen Sea intensifies melting of nearby ice shelves fringing this sector of Antarctica – have been directly linked to changes in large-scale oceanic and atmospheric circulation, including the influence of El Niño–Southern Oscillation (ENSO)-induced atmospheric wave trains propagating towards this region from the central tropical Pacific Ocean (Dutrieux et al, 2014; Jenkins et al, 2018; Nakayama et al, 2018; Steig et al, 2012) These processes together drive the detected retreat of ice shelves in the Amundsen Sea through decadal oceanographic variability (Jenkins et al, 2018). We do not analyze how the wall hinders the exchange of nutrients and influences submarine biological processes

Model setup

Results

Conclusions