NOx在雪-气之间的交换能够影响到极地大气边界层的大气成分和大气化学过程,增强极地大气边界层的氧化性,并可能影响对冰雪大气成分记录的解释.近年来,人们认识到冰雪在光照下释放NOx是极地大气边界层NOx的一个重要来源.从以下几方面对大气边界层NOx的冰雪来源进行综述:NOx冰雪来源的观测和实验证据、冰雪释放NOx的机制和影响参数、极地NOx浓度和通量以及极地冰雪NOx化学过程对环境的影响.近年来,笔者已在处于北半球中纬度的青藏高原观测到冰雪表面光照下释放出比极地高1个量级浓度水平的NOx,因此需更深入的科学研究揭示其对青藏高原大气氧化性的影响.%The exchanges of NOx between snow and air have a significant impact on the atmospheric components and photochemical processes in the overlying boundary layer, which increases the oxidizing capacity of the atmosphere and may have a decisive impact on the air signals that are retrieved from ice cores. In the recent years, sunlit snow and ice has been proved to be an important NOx source in the polar boundary layer. This paper makes a thorough review on the release ofNOx from snow and ice, including the following aspects: field observations and experimental evidences, release mechanisms and influential parameters that affect such a release process, polar NOx concentrations and fluxes, and environmental impacts of the chemical processes of NOx in the polar atmospheric boundary layer. In the Tibetan Plateau lying in the mid-latitude of Northern Hemisphere, the released NOx observed recently in the sunlit snow/ice-cover is l-order magnitude more than that in polar regions, but more in-depth scientific research is still needed to reveal its impact on the atmospheric oxidizing capacity.
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