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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

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