Antarctic Climate

This study reports the occurrence of intense atmospheric rivers (ARs) during the two large Weddell Polynya events in November 1973 and September 2017 and investigates their role in the opening events via their enhancement of sea ice melt. Few days before the polynya openings…

Antarctic sea ice plays a pivotal role in the global climate system. Forming a highly reflective, dynamic, and insulative blanket that varies seasonally in its areal coverage from ~3 × 106 km2 to ~19–20 × 106 km2, sea ice and its snow cover strongly modifies ocean…

Understanding how sea ice serves zooplankton species during the food-limited season is crucial information to evaluate the potential responses of pelagic food webs to changes in sea-ice conditions in the Southern Ocean. Stable isotope analyses (13C/12C and 15N/14N)…

Net sea ice areal extent was well above average during the first few months of 2015 (Fig. 6.8a). Monthly record extents were observed in January (7.46 × 106 km2), April (9.06 × 106 km2), and May (12.1 × 106 km2).

Antarctic sea ice performs important roles in the climate system through the formation of dense oxygen rich Antarctic Bottom Water (Johnson 2008) and modulating fluxes across the ocean/atmosphere interface within the high southern latitudes (Bourassa et al. 2013).

Both net sea ice extent (SIE) and area (SIA) were close to the 1981–2010 average for January through August 2016, after which there was a dramatic departure from the mean through to the end of the year (Fig. 6.8a). Maximum net SIE peaked on 31 August (18.44 × 106 km2)…

The Southern Ocean is disproportionately important in its effect on the Earth system, impacting climatic, biogeochemical, and ecological systems, which makes recent observed changes to this system cause for global concern.

Satellite-derived Antarctic sea ice extent has displayed a slight upward since 1979, but with strong temporal and regional variability—the drivers of which are poorly understood. Here, we conduct numerical experiments with a circum-Antarctic ocean–sea ice…

Snow is the most reflective, and also the most insulative, natural material on Earth. Consequently, it is an integral part of the sea-ice and climate systems. However, the spatial and temporal heterogeneities of snow pose challenges for observing…

Antarctic sea ice trends have to date been linked to surface winds, through sea ice motion and atmospheric thermal advection. This paper analyzes sea ice volume in 10 Coupled Model Intercomparison Project Phase 5 (CMIP5) model configurations under pre-industrial and historical climate forcings…

The Maud Rise polynya is a persistent area of open water within the sea ice cover of the Southern Ocean, which overlies an area of elevated topography called Maud Rise (66°S, 3°E) located in the eastern sector of the Weddell Sea (Fig. SB6.1a).

Overall Antarctic sea ice extent in the 2016 spring attained a record minimum for the satellite period (1979–2016), presenting an abrupt departure from the record maxima in previous years and the slight upward trend since 1979.

Fast ice is an important component of Antarctic coastal marine ecosystems, providing a prolific habitat for ice algal communities. This work examines the relationships between normalized difference indices (NDI)…

The spreading of dense shelf water (DSW) from Antarctic coastal margins to lower latitudes plays a vital role in the ocean thermohaline circulation and the global climate system. Through enhanced localized sea ice production in Antarctic coastal polynyas…

In contrast to a strong decrease in Arctic sea ice extent, overall Antarctic sea ice extent has modestly increased since 1979. Several hypotheses have been proposed for the net Antarctic sea ice expansion, including atmosphere/ocean circulation and temperature changes…

Ocean–cryosphere interactions along the Adélie and George V Land (AGVL) coast are investigated using a coupled ocean–sea ice–ice shelf model. The dominant feature of the Mertz Glacier Tongue (MGT), located at approximately 145°E, was a highly productive winter coastal polynya system…

Contrasting regional changes in Southern Ocean sea ice have occurred over the last 30 years with distinct regional effects on ecosystem structure and function.

Investigating ecological relationships between predators and their environment is essential to understand the response of marine ecosystems to climate variability and change. This is particularly true in polar regions, where sea ice (a sensitive climate variable)…

Deriving the snow depth on Antarctic sea ice is a key factor in estimating sea-ice thickness distributions from space or airborne altimeters. Using a linear regression to model snow depth from observed 'total freeboard'…

Over the past 37 years, satellite records show an increase in Antarctic sea ice cover that is most pronounced in the period of sea ice growth. This trend is dominated by increased sea ice coverage in the western Ross Sea, and is mitigated by a strong decrease in the Bellingshausen and Amundsen seas.

In 2012, Antarctic sea-ice coverage was marked by weak annual-mean climate anomalies that consisted of opposing anomalies early and late in the year (some setting new records) which were interspersed by near-average conditions for most of the austral autumn and winter. Here…

This editorial introduces a suite of articles resulting from the second Sea Ice Physics and Ecosystems eXperiment (SIPEX-2) voyage by presenting some background information on the study area and Antarctic sea-ice conditions, and summarising the key findings from the project.

Snow on Antarctic sea ice plays a complex and highly variable role in air-sea-ice interaction processes and the Earth's climate system. Using data collected mostly during the past 10 years, this paper reviews the following topics:

Antarctica. The word conjures up images of mountains draped with glaciers, ferocious seas dotted with icebergs and iconic species found nowhere else. The continent includes about one-tenth of the planet's land surface, nearly 90% of Earth's ice and about 70% of its fresh water.

Antarctic and Southern Ocean science is vital to understanding natural variability, the processes that govern global change and the role of humans in the Earth and climate system. The potential for new knowledge to be gained from future Antarctic science is substantial. Therefore…