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The flux of gases between the atmosphere and the oceans can be calculated from the product of the concentration difference across the sea surface and a kinetic term, often called a transfer velocity. The transfer velocity is frequently parameterized in terms of wind speed, although the actual exchange process is also affected by waves, bubbles, wind fetch, and less certainly by surfactants and chemical reactivity. There is currently an uncertainty of about a factor of two in using the wind speed parameterization. In view of the windiness of the Southern Ocean, transfer velocities will often be high, although there are few published in situ measurements of transfer rates made in the region. Data for gas concentration fields in the Southern Ocean are generally sparse compared to other better studied oceanic areas. In this paper we discuss what is known for the region for carbon dioxide, including the oceanic sink for man-made inputs to the atmosphere; dimethyl sulphide, where there appears to be a substantial source, which has the potential for a significant climatic effect due to the low particulate loading in the region; and organo-halogen and alkyl nitrate gases, where marine emissions may play an important role in controlling the oxidation capacity of the Antarctic atmosphere. [ABSTRACT FROM AUTHOR]

Small Unmanned Meteorological Observer (SUMO) unmanned aerial vehicles (UAVs) were used to observe atmospheric boundary layer temperature profiles in the vicinity of McMurdo Station, Antarctica during January and September 2012. The observations from four flight days are shown and exhibit a variety of boundary layer temperature profiles ranging from deep, well-mixed conditions to strong, shallow inversions. Repeat UAV profiles over short periods of time (tens of minutes to several hours) revealed rapid changes in boundary layer structure. The success of the SUMO flights described here demonstrates the potential for using small UAVs for Antarctic research. [ABSTRACT FROM AUTHOR]

The Antarctic climate system varies on time-scales from orbital, through millennial to sub-annual, and is closely coupled to other parts of the global climate system. We review these variations from the perspective of the geological and glaciological records and the recent historical period from which we have instrumental data (∼the last 50 years). We consider their consequences for the biosphere, and show how the latest numerical models project changes into the future, taking into account human actions in the form of the release of greenhouse gases and chlorofluorocarbons into the atmosphere. In doing so, we provide an essential Southern Hemisphere companion to the Arctic Climate Impact Assessment. [ABSTRACT FROM AUTHOR]

Recently, the Antarctic Peninsula has received more attention due to the pronounced warming in that region. Non-glaciated coastal areas on the Peninsula can be significant energy sources for the atmosphere when they are exposed during summer despite the high degree of cloud associated with the frequent passage of low pressure systems. An eddy covariance system was established in December 2002 to evaluate the turbulent energy exchanges between the atmosphere and a non-glaciated coastal area on King George Island. Monthly average downward shortwave radiation was less than 210 Wm-2 in summer. Due to the low albedo of 0.12, monthly average net radiation reached > 130 Wm-2, a magnitude that was significantly larger than the reported magnitudes of < ∼70 Wm-2 at glaciated areas with a high albedo on the Peninsula. The sum of monthly average sensible heat (< 64 Wm-2) and latent heat (< 20 Wm-2) fluxes amounted up to ∼80 Wm-2, which was an order of magnitude larger than those at glaciated areas on the Antarctic Peninsula. Given that non-glaciated areas should be enlarged if the warming continues, more attention may need to be paid to the role of non-glaciated areas in the local climate to predict climate change on the Antarctic Peninsula. [ABSTRACT FROM AUTHOR]