On the settling depth of meltwater escaping from beneath Antarctic ice shelves

Transoceanic infragravity waves impacting Antarctic ice shelves

[1] Long-period oceanic infragravity (IG) waves (ca. [250, 50] s period) are generated along continental coastlines by nonlinear wave interactions of storm-forced shoreward propagating swell. Seismic observations on the Ross Ice Shelf show that free IG waves generated along the Pacific coast of North America propagate transoceanically to Antarctica, where they induce a much higher amplitude she...

Bacteria beneath the West Antarctic ice sheet.

Subglacial environments, particularly those that lie beneath polar ice sheets, are beginning to be recognized as an important part of Earth's biosphere. However, except for indirect indications of microbial assemblages in subglacial Lake Vostok, Antarctica, no sub-ice sheet environments have been shown to support microbial ecosystems. Here we report 16S rRNA gene and isolate diversity in sedime...

Melting and freezing under Antarctic ice shelves from a combination of ice-sheet modelling and observations

Effect of Ocean Warming on West Antarctic Ice Streams and Ice Shelves

The Intergovernmental Panel on Climate Change (IPCC) has deemed the Western Antarctic Ice Sheet (WAIS) as very likely to have contributed to sea level rice over the past two decades, estimating a loss of 44 ±13 Gt/yr. Focus has shifted to the behavior and dynamics of the WAIS ice streams since ~90 % of the outward ice flux flows through the ice streams. The behavior and movement of the ice stre...

Tsunami and infragravity waves impacting Antarctic ice shelves

The responses of the Ross Ice Shelf (RIS) to the 16 September 2015 8.3 (Mw) Chilean earthquake tsunami (>75 s period) and to oceanic infragravity (IG) waves (50–300 s period) were recorded by a broadband seismic array deployed on the RIS from November 2014 to November 2016. Here we show that tsunami and IG-generated signals within the RIS propagate at gravity wave speeds ( 70 m/s) as water-ice ...