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Meteoroids of sub-milligram sizes burn up high in the Earth's atmosphere and cause streaks of plasma trails detectable by meteor radars. The altitude at which these trails, or meteors…
Antarctic sea ice is one of the largest biomes on Earth providing a critical habitat for ice algae. Measurements of primary production in Antarctic sea ice remain scarce and an observation-based estimate of primary production has not been revisited in over 30 years.
Components such as organic carbon (Corg), carbonate, opal or barite are valuable paleoceanographic proxies, enabling the reconstruction of past changes in carbon cycling under various climate regimes, particularly when 230Th-normalization is used to reconstruct particulate vertical rain rates.
Primary productivity by phytoplankton in the Southern Ocean can be limited by low iron concentrations. Iron limitation in the surface ocean around Antarctica may be alleviated by particle dissolution of dust from exposed rock, glacial flour, resuspended marine sediment, and sea ice. Ligands…
Sea ice can be interspersed vertically with both permeable and impermeable layers. These features can be smaller than a few centimetres but are important for understanding biogeochemical cycles in sea ice. Traditionally…
Antarctic Bottom Water (AABW) is the densest water mass in the world and drives the lower limb of the global thermohaline circulation. AABW is formed in only four regions around Antarctica and Cape Darnley, East Antarctica, is the most recently discovered formation region. Here…
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…
The future response of the Antarctic Slope Current (ASC) to projected transient changes in winds, radiative forcing, and meltwater input is examined in a high-resolution ocean-sea ice model. Meltwater changes are found to dominate the almost -circumpolar strengthening of the ASC.
Interleaving layers are commonly observed in the subsurface ocean near thermohaline fronts. They imply a lateral exchange of water mass properties and have been shown to influence both lateral and vertical mixing rates. We examine a set of in situ observations…
Global chemistry–climate models (CCMs) play an important role in assessing the climate and air pollution implications of aerosols and chemically reactive gases.
Global, regional and local sea?level projections rely on complex process?based models of the climate?ocean?cryosphere system. While extrapolation of observational data has been examined on global and regional scales, this approach has not yet been used for the additional complexities of coastal sea?
Antarctic ice shelves typically comprise continental meteoric ice, in situ-accumulated meteoric ice, and marine ice accumulated at the shelf base. Using borehole optical televiewer logs from across Larsen C Ice Shelf, Antarctic Peninsula, we identify and report an intermediate ice unit…
Levoglucosan (LEV) and two of its isomers, mannosan (MAN) and galactosan (GAL), are commonly used as biomass burning tracers, however 1,6-anhydro-?-D-glucofuranose (AGF), another isomer derived from biomass burning, is rarely identified or quantified in existing literature.
During the transition from the Last Glacial Maximum (LGM) to the Holocene, the atmospheric N2O mole fraction increased by 80 nmol mol?1. Using ice core measurements of N2O isotopomer ratios, we show that this increase was driven by increases in both nitrification and denitrification…
The development of the Antarctic ozone hole in late winter and spring (September–November) is the most … noticeable phenomenon in the polar stratosphere. It has appeared every season since the early 1980s within the … stratospheric polar vortex…
The largest regional drivers of current surface elevation increases in the Antarctic Ice Sheet are associated with ice flow reconfiguration in previously active ice streams, highlighting the important role of ice dynamics in mass balance calculations. Here…
Antarctic terrestrial biodiversity faces multiple threats, from invasive species to climate change. Yet no large-scale assessments of threat management strategies exist. Applying a structured participatory approach…
The Antarctic marine environment, although rich in life, is predicted to experience rapid and significant effects from climate change. Despite a revolution in the approaches used to document biodiversity…
Antarctic biodiversity faces an unknown future with a changing climate. Most terrestrial biota is restricted to limited patches of ice-free land in a sea of ice, where they are adapted to the continent's extreme cold and wind and exploit microhabitats of suitable conditions.
The Antarctic climate-diversity-invasion hypothesis (ACDI) predicts that in Antarctic soil systems, climate change should lead to increases in the abundance and diversity of indigenous assemblages. Where biological invasions have occurred, however…
Antarctic geothermal heat flow (GHF) affects the thermal regime of ice sheets and simulations of ice and subglacial meltwater discharge to the ocean, but remains poorly constrained.
The Environmental Effects Assessment Panel of the Montreal Protocol under the United Nations Environment Programme evaluates effects on the environment and human health that arise from changes in the stratospheric ozone layer and concomitant variations in ultraviolet (UV)…
Understanding how ecological, environmental and geographic features influence population genetic patterns provides crucial insights into a species' evolutionary history, as well as their vulnerability or resilience under climate change. In the Southern Ocean…
The Antarctic environment is extremely cold, windy and dry. Ozone depletion has resulted in increasing ultraviolet-B radiation, and increasing greenhouse gases and decreasing stratospheric ozone have altered Antarctica's climate.
Antarctic moss beds are sensitive to climatic conditions, and both their survival and community composition are particularly influenced by the availability of liquid water over summer. As Antarctic regions increasingly face climate pressures (e.g., changing hydrology and heat waves)…