Meteoric Influences on Stratospheric Aerosol and Clouds (MeteorStrat)

流星对平流层气溶胶和云的影响 (MeteorStrat)

• 批准号: NE/R011222/1
• 负责人: Graham Mann
• 金额: $ 82.8万
• 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: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FR011222%2F1
• 关键词: Meteoric; Influences; Stratospheric; Aerosol; Clouds

Volcanic injections of sulphur brighten the stratospheric aerosol layer with major eruptions inducing periods of strong cooling within global mean surface temperature trends.The stratospheric ozone layer shields us from harmful UV radiation, and accurately predicting how it will recover relies on predicted changes in stratospheric aerosol and polar clouds.The MeteorStrat project addresses two key knowledge gaps that limit current predictive capability of composition-climate models, both associated with the effects from the continual supply of meteoric material entering the upper atmosphere.Firstly, recent in-situ observations have confirmed findings from the late 1990s that most particles in the stratospheric aerosol layer contain refractory core of meteoric origin, posing a major challenge to the current generation of interactive stratospheric aerosol models.Secondly, how the polar stratospheric clouds, that provide the medium by which emissions of compounds such as CFCs leads to polar ozone loss, form in the Arctic has remained a persistent uncertainty, limiting the confidence of model predictions for how the ozone layer will recover.The MeteorStrat team have made two breakthrough research findings that uniquely enable to address long-standing questions in stratospheric aerosol and PSC science.Firstly, our global model "meteoric smoke interaction experiments" show major effects from extra-terrestrial material, the meteoric inclusions radically altering the vertical distribution of sulphuric particles, challenging how models predict changes in the stratospheric aerosol layer. Secondly, our laboratory PSC freezing experiments reveal that rather than ablation-generated smoke particles (which were found to be poor NAT nuclei), it is an inclusion of non-ablated meteoric fragment particles that may explain how many NAT particles nucleate in the Arctic. This project builds on these exciting research findings with two hypotheses addressing the overarching aim to assess how cosmic dust influences the composition of the stratosphere.A. That meteoric-sulphuric particles are larger, with shorter stratospheric residence times, has important consequences for how models predict decay from volcanic enhancement B. The mechanism by which solid nitric acid PSCs form in the Arctic can finally be explained by the non-ablated meteoric fragments providing the preferential NAT nucleiWe will combine our internationally-leading laboratory and modelling capabilities to test these hypotheses. Our workplan addresses the following 5 related science questions: 1. How far do the high-latitude source meteoric-sulphuric particles extend to lower latitudes and how variable is their mid-latitude abundance across different seasons and years?2. Do the larger meteoric-sulphuric particles effect a faster volcanic decay timescale and if so what are the implications for the surface cooling attributed to volcanic eruptions?3. What is the source flux and size distribution of the non-ablated "meteoric fragment" input and how do smoke or fragments transform into Junge layer meteoric-sulphuric particles?4. How do the distinctly composed meteoric fragments facilitate NAT freezing and what are the implications of the laboratory findings compared to smoke-driven parameterizations?5. Can meteoric influence explain observed PSCs and how is Arctic ozone loss enhanced?A key philosophy of the project involves gathering in situ and satellite measurement datasets to ensure model predictions are observationally-constrained and calibrated to maximise confidence in research findings. The project will provide the UK Earth System Model with vital capability to simulate future changes to the stratosphere, in particular for the effects from volcanic and potential stratospheric sulphur or particle geoengineering.

硫磺的喷发照亮了平流层气溶胶层，引发了全球平均地表温度趋势内的强烈冷却。平流层臭氧层保护我们免受有害的紫外线辐射，准确地预测它将如何恢复依赖于平流层气溶胶和极地云的预测变化。气象层项目解决了限制目前成分-气候模式预测能力的两个关键知识空白，这两个缺口都与持续供应进入高层大气的大气物质的影响有关。首先，最近的现场观测证实了20世纪90年代末的发现，平流层气溶胶中的大多数粒子包含来自大气的难熔核心，对当前一代相互作用的平流层气溶胶模型提出了重大挑战。第二，极地平流层云是如何在北极形成的，它提供了氯氟烃等化合物排放导致极地臭氧损失的媒介，这一直是一个持续存在的不确定性，限制了模型预测臭氧层将如何恢复的信心。气象层研究小组取得了两项突破性研究成果，这两项研究成果唯一能够解决平流层气溶胶和PSC科学中的长期悬而未决的问题。首先，我们的全球模型“大气烟雾相互作用实验”显示了来自地外物质的主要影响，陨石包裹体从根本上改变了硫质颗粒的垂直分布，挑战了模型预测平流层气溶胶变化的方式。其次，我们的实验室PSC冻结实验表明，与其说是烧蚀产生的烟雾颗粒(被发现是贫乏的NAT核)，不如说是包含了非烧蚀的陨石碎片颗粒，这可能解释了有多少NAT颗粒在北极成核。本项目以这些令人兴奋的研究发现为基础，提出了两个假设，以解决评估宇宙尘埃如何影响平流层组成的总体目标。a.大气中的硫磺粒子更大，平流层停留时间更短，这对模型预测火山增强的衰变有重要影响；B.北极固体硝酸PSC的形成机制最终可以用提供优先NAT核的非烧蚀陨石碎片来解释。我们将结合我们国际领先的实验室和模拟能力来检验这些假设。我们的工作计划涉及以下5个相关的科学问题：1.高纬度源陨石硫粒子延伸到低纬度地区有多远，其中纬度在不同季节和年份的丰度有多大的变化？2.较大的陨石硫粒子是否影响更快的火山衰变时间尺度？如果是，对火山喷发造成的地表冷却有何影响？3.未烧蚀的“陨星碎片”输入的源通量和大小分布是什么？烟雾或碎片如何转化为准格层陨石硫粒子？4.明显构成的陨石碎片如何促进NAT冰冻以及与烟雾驱动的参数化相比，实验室发现的影响是什么？5.大气影响能否解释观测到的PSC，以及北极臭氧损失是如何加剧的？该项目的一个关键理念涉及收集现场和卫星测量数据集，以确保模型预测受到观测约束并进行校准，以最大限度地增加对研究结果的信心。该项目将为英国地球系统模型提供模拟平流层未来变化的重要能力，特别是模拟火山和潜在的平流层硫或颗粒地球工程的影响。

项目成果

Characterization of the Extraterrestrial Magnesium Source in the Atmosphere Using a Meteoric Ablation Simulator

使用流星烧蚀模拟器表征大气中的外星镁源

• DOI: 10.1029/2018gl077427
• 发表时间: 2018
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Bones D

Ablation of Ni from micrometeoroids in the upper atmosphere: Experimental and computer simulations and implications for Fe ablation

高层大气中微流星体对镍的烧蚀：实验和计算机模拟以及对铁烧蚀的影响

• DOI: 10.1016/j.pss.2019.104725
• 发表时间: 2019
• 期刊: Planetary and Space Science
• 影响因子: 2.4
• 作者: Bones D

Recovery of the first ever multi-year lidar dataset of the stratospheric aerosol layer, from Lexington, MA, and Fairbanks, AK, January 1964 to July 1965

恢复平流层气溶胶层的第一个多年激光雷达数据集，来自马萨诸塞州列克星敦和阿拉斯加州费尔班克斯，1964 年 1 月至 1965 年 7 月

• DOI: 10.5194/essd-13-4407-2021
• 发表时间: 2021
• 期刊: Earth System Science Data
• 影响因子: 11.4
• 作者: Antuña-Marrero J

Data rescue of stratospheric aerosol observations from lidar at Lexington, MA, and Fairbanks, AK, January 1964 to July 1965.

1964 年 1 月至 1965 年 7 月，马萨诸塞州列克星敦和阿拉斯加费尔班克斯激光雷达平流层气溶胶观测数据的拯救。

• DOI: 10.5194/egusphere-egu21-14351
• 发表时间: 2021
• 作者: Antuña-Marrero J

Ship-borne lidar measurements showing the progression of the tropical reservoir of volcanic aerosol after the June 1991 Pinatubo eruption

船载激光雷达测量显示 1991 年 6 月皮纳图博火山喷发后热带火山气溶胶库的演变

• DOI: 10.5194/essd-2020-81
• 发表时间: 2020
• 作者: Antuña-Marrero J