NO_x Release from Snow and Ice Covered Surface in Polar Regions and the Tibetan Plateau

The exchanges of NOx between snow and air have significant impact on the atmospheric components and photochemical processes in the overlying boundary layer. Such exchanges increase the oxidizing capacity of the atmosphere and may have a crucial impact on the air signals that are retrieved from ice cores. In the recent years, sunlit snow and ice have been demonstrated to be important NOx sources in the polar atmospheric boundary layer. This paper makes a thorough review on the release of NOx from snow and ice, including 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, the released NOx observed recently in the sunlit snow/ice-cover is 1-order magnitude more than that in polar regions, but further scientific research is still needed to reveal its impact on the atmospheric oxidizing capacity.

不管多努力,始终追不上你

对你,我始终做不到不诚实。但话说出口的那一刻,我忽然有种想哭的冲动。一南一北,隔了巍巍秦岭和翻涌淮河,虽是同一片土地,有些东西却似乎变得遥不可及。暮雨纷纷,夜幕悄坠。窗外寒风正肆虐,我衬着薄薄的暮色展开你的信笺。干净的信纸上,第一句话便是:北京下雪了。我无声微笑。盛夏六月,我曾对你说:如果北京下雪了,一定要告诉我。无数次梦过雪落北京。