The meteorology and chemistry of high nitrogen oxide concentrations in the stable boundary layer at the South Pole

作者：W. D. Neff, Jim Crawford, M. Buhr, J. M. Nicovich, Gao Chen, Douglas D. Davis · 发表于：Atmospheric chemistry and physics · 年份：2018 · DOI：10.5194/acp-18-3755-2018 · 被引用次数：13 · 研究领域：Atmospheric chemistry and aerosols、Atmospheric Ozone and Climate、Atmospheric and Environmental Gas Dynamics

Abstract. Four summer seasons of nitrogen oxide (NO) concentrations were obtained at the South Pole (SP) during the Sulfur Chemistry in the Antarctic Troposphere (ISCAT) program (1998 and 2000) and the Antarctic Tropospheric Chemistry Investigation (ANTCI) in (2003, 2005, 2006–2007). Together, analyses of the data collected from these studies provide insight into the large- to small-scale meteorology that sets the stage for extremes in NO and the significant variability that occurs day to day, within seasons, and year to year. In addition, these observations reveal the interplay between physical and chemical processes at work in the stable boundary layer of the high Antarctic plateau. We found a systematic evolution of the large-scale wind system over the ice sheet from winter to summer that controls the surface boundary layer and its effect on NO: initially in early spring (Days 280–310) the transport of warm air and clouds over West Antarctica dominates the environment over the SP; in late spring (Days 310–340), the winds at 300 hPa exhibit a bimodal behavior alternating between northwest and southeast quadrants, which is of significance to NO; in early summer (Days 340–375), the flow aloft is dominated by winds from the Weddell Sea; and finally, during late spring, winds aloft from the southeast are strongly associated with clear skies, shallow stable boundary layers, and light surface winds from the east – it is under these conditions that the highest NO occurs. Examinati...