7, the Y-axis label for the top graph should be “TDN (μM)” and the X-axis label should

be “DIN (μM)”. The authors regret any inconvenience see more caused by these corrections. “
“Halogenated organic compounds (halocarbons) arise from two independent processes: human industrial activities and biogenic processes in the ocean. These compounds are critical to the atmosphere, as they play an essential role in the depletion of ozone in polar regions, which in turn has an important role in surface ecology (Karentz, 1991) and climate change (Thompson and Solomon, 2002), since ozone depletion buffers Antarctic climate warming induced by increased carbon dioxide concentrations. However, we know surprisingly little about the vertical and horizontal

distribution of halocarbons in the ocean or their relationship to biological processes. This is particularly true for the Antarctic, where few multidisciplinary studies have investigated the biophysical interactions that mediate halocarbon concentrations and the rates of their turnover. The waters of the Southern Ocean are extremely variable both in time and space. Broad temporal patterns are notable for the wax and wane of pack ice (Comiso and Nishio, 2008), but even within the growing season, substantial temporal variations on scales of hours, days, weeks and months in chemical and biological properties occur (Smith et al., 2011a). Decadal changes in ice concentrations have been observed (Cavalieri selleck chemicals llc et al., 2004 and Parkinson, 2004), and biophysical responses to regional reductions in ice cover have been noted (Montes-Hugo et al., 2009). The Ross Sea is the most productive continental shelf in Urocanase the Antarctic, but the Amundsen Sea also

shows very high productivity (Arrigo and van Dijken, 2004 and Smith and Comiso, 2008). Both regions are strongly influenced by the inflow of circumpolar deep water onto the shelves through troughs (Dinniman et al., 2011), but these deep intrusions rarely reach the surface in the Amundsen Sea, whereas they are mixed into the surface layer in the Ross Sea, primarily during winter in the West (Dinniman et al., 2011). The Ross Sea has five distinct water masses (Orsi and Wiederwohl, 2009), whereas the Amundsen Sea is characterized by only three (Fragoso and Smith, 2012). Phytoplankton in the Ross Sea are characterized by two functional groups: haptophytes, dominated by Phaeocystis antarctica, and diatoms. P. antarctica blooms largely during austral spring and dominates the biomass through the end of December, when it normally rapidly disappears, and diatom growth continues. However, substantial interannual variations occur ( Peloquin and Smith, 2007 and Smith et al., 2011a), and the fraction of annual production attributable to diatoms ranges from 13 to 57% ( Smith et al., 2011a). Other functional groups are observed (e.g., dinoflagellates, silicoflagellates, cryptomonads), but are much more restricted in time and space.