Sources and Impacts of Short-Lived Anthropogenic Chlorine

短寿命人为氯的来源和影响

• 批准号: NE/R001782/1
• 负责人: Martyn Chipperfield
• 金额: $ 74.79万
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2017
• 资助国家: 英国
• 起止时间: 2017 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FR001782%2F1
• 关键词: Sources; Impacts; Short; Lived; Anthropogenic

Depletion of stratospheric ozone allows larger doses of harmful solar UV radiation to reach the surface leading to increases in skin cancer and cataracts in humans and other impacts, such as crop damage. Ozone also affects the Earth's radiation balance and, in particular, ozone depletion in the lower stratosphere (LS) exerts an important climate forcing. While most long-lived ozone-depleting substances (e.g. CFCs) are now controlled by the United Nations Montreal Protocol and their abundances are slowly declining, there remains significant uncertainty surrounding the rate of ozone layer recovery. Changes in the LS may cause delayed ozone recovery or even additional depletion, and can also have important effects on climate. One key uncertainty, highlighted in the WMO/UNEP 2014 Assessment of Stratospheric Ozone Depletion, is the increasing importance of uncontrolled chlorine-containing very short-lived substances (VSLS) which can reach the LS and cause ozone depletion.While significant amounts of brominated VSLS are known to be emitted naturally from the oceans, recent publications also show a rapid, unexpected and unexplained increase in anthropogenic chlorinated VSLS (Cl-VSLS), especially in E and SE Asia. Some of these Cl-VSLS will reach the stratosphere via deep convection in the tropics (through the tropical tropopause layer) or via the Asian Summer Monsoon (ASM) or the E Asian Winter Monsoon.The Montreal Protocol is arguably the world's most successful environmental agreement. By controlling the production and emission of long-lived ODSs, it has set the ozone layer on the road to recovery. However, short-lived halogenated compounds (lifetimes <6 months) have so far not been included, based on the belief that they would not be abundant or persistent enough to have an impact. Recent observations suggest otherwise; calculations in this proposal suggest that Cl-VSLS may delay the recovery of the Antarctic Ozone Hole (to 1980 levels) by up to 30 years. Fortunately, the Montreal Protocol has a regular review process which allows amendments to deal with new threats to the ozone layer and climate, e.g. the recent 2016 success of including limits to the production of hydrofluorocarbons (HFCs).This proposal takes advantage of UEA's heritage in atmospheric halocarbon measurements to obtain novel observations of chlorine compounds in the key E/SE Asia region and in the global mid-upper troposphere. Surface observations will be targeted in the key winter periods when we know that we will be able to detect polluted emissions from China, a likely major emitter of Cl-VSLS globally. We will extend the suite of gases currently measured by the CARIBIC in-service global passenger aircraft to include several newly-identified VSLS. This will allow us to investigate the distribution of these VSLS over a much wider geographical area, to identify source regions and to assess longer term changes in their atmospheric abundance.Our observations will be combined with detailed 3-D modelling at Leeds and Lancaster, who have world-leading expertise and tools for the study of atmospheric chlorine. One model will be used in an 'inverse' mode to trace back the observations of anthropogenic VSLS to their source regions. Overall, the models will be used to quantify the flux of halogenated ozone-depleting gases to the stratosphere and to determine their ozone and climate impact. We will calculate metrics for ozone depletion and climate change and feed these through to the policy-making process (Montreal Protocol) with the collaboration of expert partners. The results of SISLAC will provide important information for future international assessments e.g. WMO/UNEP and IPCC reports.

平流层臭氧的消耗使得更大剂量的有害太阳紫外线辐射到达地表，导致人类皮肤癌和白内障的增加以及其他影响，例如农作物受损。臭氧还影响地球的辐射平衡，特别是平流层低层（LS）的臭氧消耗会产生重要的气候强迫。虽然大多数长寿命臭氧消耗物质（例如氟氯化碳）现在受到联合国《蒙特利尔议定书》的控制，并且其含量正在缓慢下降，但臭氧层恢复速度仍然存在很大的不确定性。 LS 的变化可能会导致臭氧恢复延迟甚至进一步消耗，并且还会对气候产生重要影响。 WMO/UNEP 2014 年平流层臭氧消耗评估中强调的一个关键不确定性是不受控制的含氯极短寿命物质 (VSLS) 的重要性日益增加，这些物质可以到达 LS 并导致臭氧消耗。已知是从海洋自然排放的，最近的出版物也显示人为氯化 VSLS 的快速、意外和无法解释的增加(Cl-VSLS)，特别是在东亚和东南亚。其中一些 Cl-VSLS 将通过热带深对流（通过热带对流层顶层）或通过亚洲夏季风 (ASM) 或东亚冬季风到达平流层。《蒙特利尔议定书》可以说是世界上最成功的环境协议。通过控制长寿命消耗臭氧层物质的生产和排放，臭氧层走上了恢复之路。然而，迄今为止，短寿命卤代化合物（寿命<6个月）尚未包括在内，因为人们相信它们的数量或持久性不足以产生影响。最近的观察表明情况并非如此；该提案中的计算表明，Cl-VSLS 可能会将南极臭氧空洞的恢复（恢复至 1980 年的水平）延迟长达 30 年。幸运的是，《蒙特利尔议定书》有一个定期审查程序，允许进行修订，以应对对臭氧层和气候的新威胁，例如。最近 2016 年成功纳入了氢氟碳化物 (HFC) 生产限制。该提案利用东英吉利大学在大气卤化碳测量方面的传统优势，获得东亚/东南亚关键地区和全球对流层中上层氯化合物的新观测结果。地面观测将针对关键的冬季时期，届时我们将能够检测到来自中国的污染排放，中国可能是全球 Cl-VSLS 的主要排放国。我们将扩展目前由 CARIBIC 服役的全球客机测量的气体系列，以包括几种新确定的 VSLS。这将使我们能够调查这些 VSLS 在更广泛地理区域的分布，识别源区域并评估其大气丰度的长期变化。我们的观测结果将与利兹和兰卡斯特的详细 3D 模型相结合，拥有世界领先的大气氯研究专业知识和工具。一种模型将以“逆”模式使用，以将人为 VSLS 的观测追溯到其源区域。总体而言，这些模型将用于量化卤化臭氧消耗气体进入平流层的通量，并确定其对臭氧和气候的影响。我们将计算臭氧消耗和气候变化的指标，并与专家合作伙伴合作将这些指标纳入政策制定过程（《蒙特利尔议定书》）。 SISLAC 的结果将为未来的国际评估提供重要信息，例如： WMO/UNEP 和 IPCC 报告。

项目成果

Comment on "Observation of large and all-season ozone losses over the tropics" [AIP Adv. 12, 075006 (2022)]

对“热带地区大面积全季节臭氧损失的观察”的评论 [AIP Adv.

• DOI: http://dx.10.1063/5.0121723
• 发表时间: 2022
• 期刊: AIP Advances
• 影响因子: 1.6
• 作者: Chipperfield M

Description and evaluation of the new UM-UKCA (vn11.0) Double Extended Stratospheric-Tropospheric (DEST vn1.0) scheme for comprehensive modelling of halogen chemistry in the stratosphere

用于平流层卤素化学综合建模的新 UM-UKCA (vn11.0) 双扩展平流层-对流层 (DEST vn1.0) 方案的描述和评估

• DOI: http://dx.10.5194/gmd-16-6187-2023
• 发表时间: 2023
• 期刊: Geoscientific Model Development
• 影响因子: 5.1
• 作者: Bednarz E

Description and evaluation of the new UM-UKCA (vn11.0) Double Extended Stratospheric-Tropospheric (DEST vn1.0) scheme for comprehensive modelling of halogen chemistry in the stratosphere

用于平流层卤素化学综合建模的新 UM-UKCA (vn11.0) 双扩展平流层-对流层 (DEST vn1.0) 方案的描述和评估

• DOI: http://dx.10.5194/gmd-2022-215
• 发表时间: 2022
• 作者: Bednarz E

Gravitational separation of Ar/N2 and age of air in the lowermost stratosphere in airborne observations and a chemical transport model

Ar/N 的重力分离

• DOI: http://dx.10.5194/acp-20-12391-2020
• 发表时间: 2020
• 期刊: Atmospheric Chemistry and Physics
• 影响因子: 6.3
• 作者: Birner B

Investigation of East Asian Emissions of CFC-11 Using Atmospheric Observations in Taiwan

利用台湾大气观测调查东亚 CFC-11 排放量

• DOI: 10.1021/acs.est.9b06433
• 发表时间: 2020-03-03
• 期刊: Environmental Science & Technology
• 影响因子: 11.4
• 作者: Karina E. Adcock;M. Ashfold;C. Chou;Lauren J. Gooch;Norfazrin Mohd Hanif;J. Laube;D. Oram;Chang‐Feng Ou‐Yang;Marios Panagi;W. Sturges;C. Reeves
• 通讯作者: C. Reeves