Nighttime OClO in the winter Arctic vortex
Nighttime OClO in the winter Arctic vortex
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冬季北极涡旋中的夜间 OClO
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
T. Bui
中科院分区：
文献类型：
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作者：
T. Canty;E. Rivière;R. Salawitch;G. Berthet;J. Renard;K. Pfeilsticker;M. Dorf;A. Butz;H. Bösch;R. Stimpfle;D. M. Wilmouth;E. Richard;D. Fahey;P. Popp;M. Schoeberl;L. Lait;T. Bui
[1]我们发现，在2000年冬季的北极涡旋OClO的夜间配置文件被高估，近2倍，使用等熵轨迹模型约束观测配置文件的ClOx（ClO + 2 × ClOOCl）和BrO。计算出的夜间OClO的丰度被证明是敏感的丰富的溴氧（溴+溴氯），在最近的日出/日落过渡的空气包裹的历史细节，和BrCl产量从反应溴+氯。许多不确定性被认为是，测量和模拟夜间OClO之间的差异似乎是强大的。这种差异表明OClO的产生比标准光化学所暗示的要慢。如果BrO + ClO反应的BrCl产率从7%（JPL 2002值）增加到11%（接近不确定度的上限），则发现测量值与模型夜间OClO之间具有良好的一致性。这项研究强调了准确的知识的重要性，溴+ ClO反应动力学以及空气包裹轨迹正确的解释夜间OClO。这些因素对解释在微光（90° ≤ SZA ≤ 92°）期间获得的OClO观测结果的影响要小得多，此时光解过程仍然活跃。
[1] We show that a nighttime profile of OClO in the Arctic vortex during the winter of 2000 is overestimated, by nearly a factor of 2, using an isentropic trajectory model constrained by observed profiles of ClOx (ClO + 2 × ClOOCl) and BrO. Calculated abundances of nighttime OClO are shown to be sensitive to the abundance of BrOx (BrO + BrCl), details of the air parcel history during the most recent sunrise/sunset transitions, and the BrCl yield from the reaction BrO + ClO. Many uncertainties are considered, and the discrepancy between measured and modeled nighttime OClO appears to be robust. This discrepancy suggests that production of OClO occurs more slowly than implied by standard photochemistry. If the yield of BrCl from the reaction of BrO + ClO is increased from 7% (JPL 2002 value) to 11% (near the upper limit of the uncertainty), good agreement is found between measured and modeled nighttime OClO. This study highlights the importance of accurate knowledge of BrO + ClO reaction kinetics as well as air parcel trajectories for proper interpretation of nighttime OClO. These factors have a considerably smaller impact on the interpretation of OClO observations obtained during twilight (90° ≤ SZA ≤ 92°), when photolytic processes are still active.