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Climate and Glacier Dynamics
Climate History
Ice-core record
- atmospheric chemistry,
paleoclimate, ice dynamics Glacier Precipitation
Atmospheric Warming/ ice ux Wave-shelf
Circulation Changes interactions
Ice-shelf buttressing
Ocean
Foehn Winds Basal melting Hydrofracture Warming/
and heat exchange Circulation
Bedrock uplift - Changes
- record of past and Sub-ice-shelf Circulation
present deglaciation; Meltwater ux
local mantle viscosity Stranded
km 1 Glacier glacial deposits
- record of ice extent
Glacier extent and elevation
extent at LGM
today
West East
0 Remaining Ice Shelf
LGM ice sheet LGM ice shelf
Sea oor morphology

0 400
Sedimentary Dynamics km

biologic productivity
Meltwater and Ecosystem Dynamics
sediment ux
resuspension and
lateral advection Terrigenous Photosynthetic ux
sediments
Grounding zone
Diatomaceous wedges Open-marine
ecosystem
sediments Sub-ice-shelf
Sub-ice-shelf Circulation ecosystem
Meltwater and
sediment ux
Geochemical and geothermal ux
Figure 1. Schematic cross section through the Antarctic Peninsula showing the linked sedimentary, oceanographic, cryospheric, and biological
systems from the western fjords to the Larsen embayment that were studied as part of the interdisciplinary LARISSA program. IRD—ice-rafted debris;
LGM—Last Glacial Maximum.

and northwestern Weddell Seas. However, Scambos et al., 2014). The rapid changes in System Science (AISS) program. The col-
since ca. 2000, the warming trend has the Larsen Ice Shelf and northern Antarctic laboration of investigators spanned several
moderated (Turner et al., 2016), and a slight Peninsula region impacted an intercon- universities across the United States, and
cooling has been observed since 2006 nected set of polar systems, presenting a included research partners in seven coun-
(Blunden and Arndt, 2012). During this natural laboratory for investigating an area tries. Three major research cruises and six
period, sea-ice conditions in the north‐ of the Antarctic undergoing the kinds of field visits were conducted over six years,
western Weddell Sea have been generally effects anticipated in other areas under con- beginning in 2009. Major cruises were con-
heavier, and landfast sea ice has persisted tinued warming. The component systems ducted on the U.S. RV/IB NB Palmer and
in the Larsen A and Larsen B embayments have interrelated physical and ecological were supported by shorter cruises on the
through several austral summers since 2012. responses spanning annual to multi- R/V LM Gould. International logistical and
Disintegration of the ice shelves had millennial temporal scales (Fig. 1). field support included a cruise on the RV/
large subsequent impacts on the region. The LARsen Ice Shelf System Antarctica IB Araon with the Korea Polar Research
Tributary glaciers of the ice shelves showed (LARISSA) project was designed to study Institute, Twin Otter air support out of
significant acceleration and drawdown the evolution of the northern Larsen from Rothera Station from the British Antarctic
following the event (Scambos et al., 2004). a holistic perspective. As part of the 4th Survey, logistical and collaborative support
Regionally, increased ice flow from the International Polar Year (2007–2009), a set from Instituto Antártico Argentino, and,
Larsen A and Larsen B tributary glaciers of multi-institution grants were awarded finally, remotely operated vehicle opera-
now contributes a net ~10 Gt/yr of ice under the newly created U.S. National tions from the University of Ghent,
mass to the oceans (Berthier et al., 2012; Science Foundation Antarctic Integrated Belgium. While the research has produced

www.geosociety.org/gsatoday 5