The Common Representative Intermediates Mechanism version 2 in the United Kingdom Chemistry and Aerosols Model
The Common Representative Intermediates Mechanism version 2 in the United Kingdom Chemistry and Aerosols Model
复制标题
英国化学和气溶胶模型中的通用代表中间体机制第 2 版
DOI：
10.1002/essoar.10505092.1
复制
发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Archer-Nicholls S
中科院分区：
文献类型：
--
作者：
Archer-Nicholls S
我们将共同代表性中间体机制版本2，还原5（CRIV 2-R5）的实施记录到英国化学和气溶胶模型（UKCA）版本10.9中。该机制与StratTrop机制已经使用的平流层化学相结合，如UKCA和英国地球系统模型（UKESM 1）所使用的那样，以创建一个新的CRI-Strat机制。CRI-Strat模拟非甲烷挥发性有机化合物（NMVOCs）的更全面处理，并通过主化学机理（MCM）提供可追溯性。总的来说，CRI-Strat模拟了613个反应中233个物种的化学竞争（相比之下，现有StratTrop机制中有87个物种和305个反应）。然而，虽然比StratTrop复杂两倍多，但新机制的计算成本仅高出75%。利用UKCA模型中的StratTrop机制，对CRI-Strat进行了一系列现场和遥感观测和模拟评估。据发现，它增加了近地面臭氧的产生，导致臭氧浓度高于地面观测。然而，CRI-Strat的臭氧损失也更大，导致排放源的臭氧减少，对流层臭氧负担与StratTrop相似。CRI-Strat也比StratTrop产生更多的一氧化碳，特别是生物源VOC排放源的顺风，但氮氧化物的负担较低，因为更多的转化为水库物种。对流层臭氧和氮收支的变化对NMVOC排放的处理很敏感，这突出表明需要减少这些排放的不确定性，以改善对流层化学成分的代表性。
We document the implementation of the Common Representative Intermediates Mechanism version 2, reduction 5 (CRIv2-R5) into the United Kingdom Chemistry and Aerosol model (UKCA) version 10.9. The mechanism is merged with the stratospheric chemistry already used by the StratTrop mechanism, as used in UKCA and the UK Earth System Model (UKESM1), to create a new CRI-Strat mechanism. CRI-Strat simulates a more comprehensive treatment of non-methane volatile organic compounds (NMVOCs) and provides traceability with the Master Chemical Mechanism (MCM). In total, CRI-Strat simulates the chemistry of 233 species competing in 613 reactions (compared to 87 species and 305 reactions in the existing StratTrop mechanism). However, while more than twice as complex than StratTrop, the new mechanism is only 75% more computationally expensive. CRI-Strat is evaluated against an array of in situ and remote sensing observations and simulations using the StratTrop mechanism in the UKCA model. It is found to increase production of ozone near the surface, leading to higher ozone concentrations compared to surface observations. However, ozone loss is also greater in CRI-Strat, leading to less ozone away from emission sources and a similar tropospheric ozone burden compared to StratTrop. CRI-Strat also produces more carbon monoxide than StratTrop, particularly downwind of biogenic VOC emission sources, but has lower burdens of nitrogen oxides as more is converted into reservoir species. The changes to tropospheric ozone and nitrogen budgets are sensitive to the treatment of NMVOC emissions, highlighting the need to reduce uncertainty in these emissions to improve representation of tropospheric chemical composition.