Annie Foppert

University of Tasmania · Institute for Marine and Antarctic Studies (IMAS)

The Southern Ocean, which surrounds Antarctica, is unlike any other ocean on Earth. It is home to the world’s most powerful currents, biggest waves, craziest ice, and wildest animals. Despite its remoteness, the Southern Ocean plays a major role in Earth’s climate. The Southern Ocean connects and stirs together the other major oceans. The fast-flow...

A holistic review is given of the Southern Ocean dynamic system, in the context of the crucial role it plays in the global climate and the profound changes it is experiencing. The review focuses on connections between different components of the Southern Ocean dynamic system, drawing together contemporary perspectives from different research commun...

The Antarctic Circumpolar Current (ACC) in the Southern Ocean is a nearly zonal current encircling Antarctica, driven by strong westerlies that have intensified in recent decades. The current acts as a barrier between warmer water equatorward and colder water poleward. Meanders form in regions where the current encounters strong topographic changes...

The East Antarctic Ice Sheet contains the vast majority of Earth’s glacier ice (about 52 metres sea-level equivalent), but is often viewed as less vulnerable to global warming than the West Antarctic or Greenland ice sheets. However, some regions of the East Antarctic Ice Sheet have lost mass over recent decades, prompting the need to re-evaluate i...

Meanders formed where the Antarctic Circumpolar Current (ACC) interacts with topography have been identified as dynamical hot spots, characterized by enhanced eddy energy, momentum transfer, and cross-front exchange. However, few studies have used observations to diagnose the dynamics of ACC standing meanders. We use a synoptic hydrographic survey...

Physical Oceanography - Mesoscale and Larger - Session PL07 - Mechanisms for Variability, Circulation, and Transformation of Water Masses in the Southern Ocean

Changes in properties and quantity of Antarctic Bottom Water (AABW) have major implications for the climate system, through sequestration of heat and carbon into, and ventilation of, the abyssal ocean. Yet, it remains one of the most difficult water masses to observe. An array of 12 Deep Argo floats, capable of profiling from the surface to the sea...

There are two varieties of Antarctic Bottom Water present in the Australian Antarctic Basin (AAB): locally produced Adélie Land Bottom Water (ALBW) and distantly produced Ross Sea Bottom Water (RSBW). Between 2014 and 2018, RSBW has rebounded from a multidecade freshening trend. The return of the salty RSBW to the AAB is revealed by six Deep Argo f...

Antarctic Bottom Water (AABW) supplies the lower limb of the global overturning circulation, ventilates the abyssal ocean and sequesters heat and carbon on multidecadal to millennial timescales. AABW originates on the Antarctic continental shelf, where strong winter cooling and brine released during sea ice formation produce Dense Shelf Water, whic...

An unusual double-thermostad warm-core ring of the Gulf Stream was discovered in the Slope Sea, south of Georges Bank, during the R/V Endeavor Cruise 578 in May 2016. The ring’s stratification was peculiar as it included two thermostads at, respectively, 100-200 m (T=18.5°C, S=36.53) and 250-500 m (T=16.7°C, S=36.35). Extensive use of satellite dat...

Circumpolar Deep Water (CDW) transport across the Antarctic continental slope regulates the delivery of heat to the shelf and its availability to melt floating ice shelves. The cross‐slope density field, calculated from profiles collected by conductivity‐temperature‐depth‐tagged marine mammals on the East Antarctic slope (0–160°E, above 1,000‐ to 3...

The dynamics of an oceanic storm track-where energy and enstrophy transfer between the mean flow and eddies-are investigated using observations from an eddy-rich region of the Antarctic Circumpolar Current downstream of the Shackleton Fracture Zone (SFZ) in Drake Passage. Four years of measurements by an array of current- and pressure-recording inv...

Eddy heat flux (EHF) is a predominant mechanism for heat transport across the zonally unbounded mean flow of the Antarctic Circumpolar Current (ACC). Observations of dynamically relevant, divergent, four-year mean EHF in Drake Passage from the cDrake project, as well as previous studies of atmospheric and oceanic storm tracks, motivates the use of...

The Polar Front (PF) is studied using 4 years of data collected by a line of current- and pressure-recording inverted echo sounders in Drake Passage complemented with satellite altimetry. The location of the PF is bimodal in latitude. A northern and southern PF exist at separate times, separated geographically by a seafloor ridge - the Shackleton F...