Meteoric Influences on Stratospheric Aerosol and Clouds (MeteorStrat)

Lead Research Organisation: University of Leeds
Department Name: School of Earth and Environment

Abstract

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 nuclei

We 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.

Planned Impact

MeteorStrat is focussed on two key features of the Earth's atmosphere, the stratospheric aerosol layer and the stratospheric ozone layer. The research will quantify how both layers are influenced by cosmic dust particles, which are continuously entrained down into the upper atmosphere as small meteoroids burn up during atmospheric entry. The research will also lead to better understanding of natural influences on climate, principally from volcanic injections of sulphur.

Our science will inform upcoming international assessments of climate (CMIP6) and of the stratospheric aerosol (SSiRC) and will be of direct interest to government departments, chiefly the BEIS "Science and Innovation for Climate and Energy" directorate and the DEFRA "Strategic Evidence and Analysis Team".

Results from MeteorStrat will feed into the upcoming IPCC AR6 assessment and any future WMO/UNEP ozone or stratospheric aerosol assessments. We have been heavily engaged with these in the past, with co-I Chipperfield serving as convenor or lead authors for several WMO/UNEP assessments.

We have budgeted to fund a 1-day workshop during year 3 of the project (autumn 2020) to engage with other leading scientists, media and government civil servants on the effects of cosmic particles on stratospheric aerosol and PSCs.

MeteorStrat will further develop community modelling tools for chemistry-climate and Earth System Modelling studies and the wider public will benefit from more robust predictions of future stratospheric change.

Our existing collaborations with the UK Met Office and the European Centre for Medium-range Weather Forecasts, and the inclusion of the GLOMAP aerosol scheme within the UK Earth System Model and the flagship atmospheric monitoring system C-IFS provides guaranteed impact from the model improvements.

The general public has a keen interest in the environment, and climate change in particular.

It remains extremely important to engage with the public and to provide latest scientific evidence related to these issues. We already do this and MeteorStrat will increase our efforts in this regard.

As such, policy makers, national and European meteorological services and the general public will all benefit from the research findings from this project.

Publications

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publication icon
Aylett T (2019) Optical properties of meteoric smoke analogues in Atmospheric Chemistry and Physics

 
Description The crystal formation of nitric acid trihydrate (NAT) in the absence of water ice is important for a subset of polar stratospheric clouds (PSCs) and thereby ozone depletion. It has been suggested that either frag- mented meteoroids or meteoric smoke particles (MSPs), or possibly both, are important as heterogeneous nuclei of these crystals.

Previous work has focused on the nucleating ability of meteoric material in nitric acid in the absence of sulfuric acid. However, it is known that when immersed in stratospheric sulfuric acid droplets, metal- containing meteoric material particles partially dissolve and components can reprecipitate as silica and alumina that have different morphologies to the original meteoric material.

Hence, in this study, we experimentally and theoretically explore the relative role that sulfuric acid-processed MSPs and meteoric fragments may play in NAT nucleation in PSCs.

We compared meteoric fragments that had recently been prepared (by milling a meteorite sample) to a sample annealed under conditions designed to simulate heating during entry into the Earth's atmosphere. Whilst the addition of sulfuric acid decreased the nucleating ability of the recently milled meteoric material relative to nucleation in binary nitric acid-water solutions (at similar NAT saturation ratio), the annealed meteoric fragments nucleated NAT with a similar effectiveness in both solutions.

However, combining our results with measured fluxes of meteoric material to the Earth, sedimentation modelling and recent experiments on fragmentation of incoming meteoroids suggests that it is unlikely for there to be sufficient fragments to contribute to the nucleation of crystalline NAT particles.

We then considered silica formed from sulfuric acid-processed MSPs. Our previous work showed that nanoparticulate silica (radius ~ 6 nm) is a relatively poor promoter of nucleation compared with micron-scaled silica particles, which were more effective.

Using a Classical Nucleation Theory model, we present evidence that nucleation of NAT on acid-processed MSPs, where the primary grain size is tens of nanometres, is also effective enough to contribute to NAT crystals in early season PSCs where there is an absence of ice.

This is a key finding, demonstrating both experimentally and theoretically, that crystal nucleation in PSCs and resulting ozone depletion relies on an accurate understanding of the transport and chemical processing of MSPs.

This will affect estimated sensitivity of stratospheric chemistry to rare events such as large volcanic eruptions and long-term forecasting of ozone recovery in a changing climate.
Exploitation Route The effects of meteoric aerosol particles in providing nuclei to nucleate polar stratospheric clouds is likely to have important consequences for the ways that the January 2022 Hunga-Tonga eruption affects the 2023 Antarctic ozone hole and effect the polar ozone depletion in the Arctic in the upcoming 2023/2024 and 2024/2025 winters.

The meteoric influences on the stratosphere are likely to be one of the aspects that affects the stratospheric water vapour from the Hunga-Tonga eruption as it descends into the polar vortex within the deep branch of the stratospheric Brewer-Dobson circulation.

The MeteorStrat PI Dr. Graham Mann is one of four international scientists co-leading a new SPARC activity on the Hunga Tonga impacts on the stratosphere, and this activity is co-ordinating a special report to feed into the 2026 WMO/UNEP Scientific Assessment of Ozone Depletion.
Sectors Environment

Government

Democracy and Justice

 
Description The new Leeds aerosol modelling capability for meteoric-sulphuric particles within the stratospheric aerosol layer has now been added to the volcanic/stratospheric aerosol forecasting capability developed within the 2nd phase of the "Development of global aerosol aspects" consortium to progress the Composition-IFS (C-IFS) modelling system, which provides operational atmospheric composition forecasts and re-analyses within the flagship European "Copernicus" atmospheric monitoring system (CAMS). The Leeds aerosol module GLOMAP is now validated within the pre-operational cycle for C-IFS, and the volcanic/stratospheric aerosol capability of C-IFS-GLOMAP now incorporates also the simulated interactions between meteoric smoke particles and sulphuric acid aerosol in the stratosphere (both represented within GLOMAP). The new CAMS capability IFS-GLOMAP (also known as "ICBG") for predicting the evolution of the stratospheric aerosol layer, including for future major volcanic eruption, was upgraded in 2020 to include also the meteoric-sulphuric capability. The European modelling capability within the ECMWF forecasting system now has the equivalent capability from GA4 UM-UKCA already submitted for the international VolMIP Tambora-ISA ensemble (see Marshall et al., 2018 and Clyne et al., 2021 papers within Atmospheric Chemistry and Physics) and the 4 co-ordinated international modelling experiments within the ISA-MIP initiative (see Timmreck et al., GMD, 2018) An additional capability added to IFS-GLOMAP during 2020 involves the interactive volcanic aerosol also effecting heterogeneous chemistry for impacts on the stratospheric ozone layer, via collaboration with the BIRA Brussels institute for space aeronomy and the Netherlands national meteorological service KNMI. With the capability to be further integrated into the Copernicus modelling system in the upcoming 3rd phase of CAMS, the volcanic aerosol capability is planned to progress to effect radiative transfer for volcano-climate impacts within forecasts, then progressing to influence the range of Copernicus user products across the other Copernicus activities such as surface climate metrics, satellite retrievals and industry (e.g. solar energy). We expect the impacts from this new volcanic aerosol capability to continue to grow in the coming years as this 3rd phase of CAMS (2021 to 2023) progresses.
First Year Of Impact 2019
Sector Environment
Impact Types Societal

Policy & public services

 
Title Data relating to "The importance of acid processed meteoric smoke relative to meteoric fragments for crystal nucleation in polar stratospheric clouds" 
Description  
Type Of Material Database/Collection of data 
Year Produced 2023 
Provided To Others? Yes  
URL https://archive.researchdata.leeds.ac.uk/1148/
 
Description Collaboration with US research teams re: measurements of stratospheric aerosol 
Organisation National Center for Atmospheric Research
Country United States 
Sector Public 
PI Contribution At the Dec 2018 AGU fall meeting in Washington DC, Prof. Deshler, Dr. Kalnajs and Dr. Mann discussed the findings of the Leeds research team's UM-UKCA stratospheric aerosol model predictions, and invited Leeds to participate as an additional modelling activity aligned to the 2019 and 2020 field campaigns (see below). The Leeds MeteorStrat PI (Mann) joined the initial Skype planning meeting in January 2019 and explained the basis for how the Leeds team could contribute with initial simulations being run by the Leeds PDRA with work over the next 6-9 months to prepare for a bigger UK modelling contribution to the Apr-Jun 2020 campaign. Prof. Deshler originally planned to visit Leeds in September 2019 to share the data from the 1st phase campaign, and discuss the dedicated model experiments the Leeds team are running, to understand the progression of the meteoric-sulphuric particle abundance as the polar vortex forms and deepens through Antarctic autumn and into winter. With the Leeds SSiRC workshop scheduled for March 2020, and Dr. Kalnajs unavailable in Sept 2019, that visit was postponed to later in the project. The ASPEN field campaign 2nd phase was scheduled to take place in April to June 2020, with then Prof. Deshler planning to visit later in 2020. With the CoViD pandemic the 2nd phase of ASPEN had to be postponed, but was able to be re-scheduled to April-May 2023. Since the eruption of the Hunga-Tonga submarine volcanic eruption on 15th January 2022 the Southern Hemisphere stratosphere is experiencing very strongly enhanced concentrations of stratospheric water vapour, and although the stratospheric layer of enhanced water vapour remained outside the 2022 Antarctic vortex, since November 2022 the high-latitude Southern hemisphere stratosphere has much higher stratospheric water vapour than usual. This re-scheduled 2nd phase of the ASPEN high-altitude balloon campaign taking place in April and May 2023 is uniquely placed to make the first in-situ measurements of any earlier and enhanced polar stratospheric clouds expected due to the higher-than-usual stratospheric water vapour mixing ratios. We are continuing to interact with the University of Colorado team (Prof. Terry Deshler, Dr. Lars Kalnajs) and aim to compare simulations of the PSCs from the MeteorStrat project to these in-situ balloon measurements. The lead PI (Mann) and global aerosol modelling PDRA (Kamalika Sengupta) discussed with the NOAA and Univ. Denver project partners strategies for comparing the interactive stratospheric aerosol simulations to the two in-situ stratospheric aerosol measurement datasets. Dr. Dan Murphy visited Leeds in November 2019 and Prof. James C. Wilson visited Leeds in June 2019.
Collaborator Contribution Prof. Terry Deshler (Univ. Wyoming) is a project partner on the MeteorStrat project, and at the time the Leeds team were writing the MeteorStrat proposal, Prof. Deshler was preparing an NSF proposal seeking funding for two field campaign phases at McMurdo station in the Antarctic (in collaboration with Lars Kalnajs at NCAR, on high-altitude-balloon-borne condensation particle counter and optical particle counter measurements) which would measure at an unprecedented altitude (above 35km due new lightweight design, and during the autumn-winter period rather than the usual winter-spring period (usually selected due to monitoring of the ozone hole) The NSF research grant also involves Brian Toon's stratospheric aerosol and PSC modelling group at NCAR/Colorado Univ) to combine the measurements and modelling capabilities to interpret what the observations measure in the two autumn-winter seasons (Apr to Jun 2019 and Apr to Jun 2020). During his visit to Univ. Leeds in November 2019, Dr. Dan Murphy (Program Lead of the Aerosol Properties and Processes group, NOAA Chemical Services Division, Boulder, Colorado) contributed measurement datasets from the PALMS laser mass spectrometer instrument from multiple field campaigns, compiled into a form that enabled to compare with the interactive stratospheric aerosol simulations the Leeds global modelling PDRA (Kamalika Sengupta) has carried out for the project. During his visit to Univ. Leeds in June 2019, Prof. James C. Wilson (Dept. of Mechanical and Materials Engineering, Univ. Denver), discussed with the Leeds MeteorStrat team strategies for comparing to the database of high-altitude aerosol particle size distribution measurements (from multiple field campaigns sampling the lower stratosphere, including in the period after the 1991 Pinatubo eruption).
Impact Agreed contribution to science aligned to the Antarctic stratospheric aerosol NSF project, and to the NOAA and Univ. Denver stratospheric aerosol measurement datasets, and research papers are planned to compare the model simulations to these measurements, including the Apr-June 2019 McMurdo field campaign measurements, and/or the Hunga-Tonga-enhanced aerosol and PSCs in Apr-June 2023.
Start Year 2018
 
Description Collaboration with US research teams re: measurements of stratospheric aerosol 
Organisation National Oceanic And Atmospheric Administration
Country United States 
Sector Public 
PI Contribution At the Dec 2018 AGU fall meeting in Washington DC, Prof. Deshler, Dr. Kalnajs and Dr. Mann discussed the findings of the Leeds research team's UM-UKCA stratospheric aerosol model predictions, and invited Leeds to participate as an additional modelling activity aligned to the 2019 and 2020 field campaigns (see below). The Leeds MeteorStrat PI (Mann) joined the initial Skype planning meeting in January 2019 and explained the basis for how the Leeds team could contribute with initial simulations being run by the Leeds PDRA with work over the next 6-9 months to prepare for a bigger UK modelling contribution to the Apr-Jun 2020 campaign. Prof. Deshler originally planned to visit Leeds in September 2019 to share the data from the 1st phase campaign, and discuss the dedicated model experiments the Leeds team are running, to understand the progression of the meteoric-sulphuric particle abundance as the polar vortex forms and deepens through Antarctic autumn and into winter. With the Leeds SSiRC workshop scheduled for March 2020, and Dr. Kalnajs unavailable in Sept 2019, that visit was postponed to later in the project. The ASPEN field campaign 2nd phase was scheduled to take place in April to June 2020, with then Prof. Deshler planning to visit later in 2020. With the CoViD pandemic the 2nd phase of ASPEN had to be postponed, but was able to be re-scheduled to April-May 2023. Since the eruption of the Hunga-Tonga submarine volcanic eruption on 15th January 2022 the Southern Hemisphere stratosphere is experiencing very strongly enhanced concentrations of stratospheric water vapour, and although the stratospheric layer of enhanced water vapour remained outside the 2022 Antarctic vortex, since November 2022 the high-latitude Southern hemisphere stratosphere has much higher stratospheric water vapour than usual. This re-scheduled 2nd phase of the ASPEN high-altitude balloon campaign taking place in April and May 2023 is uniquely placed to make the first in-situ measurements of any earlier and enhanced polar stratospheric clouds expected due to the higher-than-usual stratospheric water vapour mixing ratios. We are continuing to interact with the University of Colorado team (Prof. Terry Deshler, Dr. Lars Kalnajs) and aim to compare simulations of the PSCs from the MeteorStrat project to these in-situ balloon measurements. The lead PI (Mann) and global aerosol modelling PDRA (Kamalika Sengupta) discussed with the NOAA and Univ. Denver project partners strategies for comparing the interactive stratospheric aerosol simulations to the two in-situ stratospheric aerosol measurement datasets. Dr. Dan Murphy visited Leeds in November 2019 and Prof. James C. Wilson visited Leeds in June 2019.
Collaborator Contribution Prof. Terry Deshler (Univ. Wyoming) is a project partner on the MeteorStrat project, and at the time the Leeds team were writing the MeteorStrat proposal, Prof. Deshler was preparing an NSF proposal seeking funding for two field campaign phases at McMurdo station in the Antarctic (in collaboration with Lars Kalnajs at NCAR, on high-altitude-balloon-borne condensation particle counter and optical particle counter measurements) which would measure at an unprecedented altitude (above 35km due new lightweight design, and during the autumn-winter period rather than the usual winter-spring period (usually selected due to monitoring of the ozone hole) The NSF research grant also involves Brian Toon's stratospheric aerosol and PSC modelling group at NCAR/Colorado Univ) to combine the measurements and modelling capabilities to interpret what the observations measure in the two autumn-winter seasons (Apr to Jun 2019 and Apr to Jun 2020). During his visit to Univ. Leeds in November 2019, Dr. Dan Murphy (Program Lead of the Aerosol Properties and Processes group, NOAA Chemical Services Division, Boulder, Colorado) contributed measurement datasets from the PALMS laser mass spectrometer instrument from multiple field campaigns, compiled into a form that enabled to compare with the interactive stratospheric aerosol simulations the Leeds global modelling PDRA (Kamalika Sengupta) has carried out for the project. During his visit to Univ. Leeds in June 2019, Prof. James C. Wilson (Dept. of Mechanical and Materials Engineering, Univ. Denver), discussed with the Leeds MeteorStrat team strategies for comparing to the database of high-altitude aerosol particle size distribution measurements (from multiple field campaigns sampling the lower stratosphere, including in the period after the 1991 Pinatubo eruption).
Impact Agreed contribution to science aligned to the Antarctic stratospheric aerosol NSF project, and to the NOAA and Univ. Denver stratospheric aerosol measurement datasets, and research papers are planned to compare the model simulations to these measurements, including the Apr-June 2019 McMurdo field campaign measurements, and/or the Hunga-Tonga-enhanced aerosol and PSCs in Apr-June 2023.
Start Year 2018
 
Description Collaboration with US research teams re: measurements of stratospheric aerosol 
Organisation University of Denver
Country United States 
Sector Academic/University 
PI Contribution At the Dec 2018 AGU fall meeting in Washington DC, Prof. Deshler, Dr. Kalnajs and Dr. Mann discussed the findings of the Leeds research team's UM-UKCA stratospheric aerosol model predictions, and invited Leeds to participate as an additional modelling activity aligned to the 2019 and 2020 field campaigns (see below). The Leeds MeteorStrat PI (Mann) joined the initial Skype planning meeting in January 2019 and explained the basis for how the Leeds team could contribute with initial simulations being run by the Leeds PDRA with work over the next 6-9 months to prepare for a bigger UK modelling contribution to the Apr-Jun 2020 campaign. Prof. Deshler originally planned to visit Leeds in September 2019 to share the data from the 1st phase campaign, and discuss the dedicated model experiments the Leeds team are running, to understand the progression of the meteoric-sulphuric particle abundance as the polar vortex forms and deepens through Antarctic autumn and into winter. With the Leeds SSiRC workshop scheduled for March 2020, and Dr. Kalnajs unavailable in Sept 2019, that visit was postponed to later in the project. The ASPEN field campaign 2nd phase was scheduled to take place in April to June 2020, with then Prof. Deshler planning to visit later in 2020. With the CoViD pandemic the 2nd phase of ASPEN had to be postponed, but was able to be re-scheduled to April-May 2023. Since the eruption of the Hunga-Tonga submarine volcanic eruption on 15th January 2022 the Southern Hemisphere stratosphere is experiencing very strongly enhanced concentrations of stratospheric water vapour, and although the stratospheric layer of enhanced water vapour remained outside the 2022 Antarctic vortex, since November 2022 the high-latitude Southern hemisphere stratosphere has much higher stratospheric water vapour than usual. This re-scheduled 2nd phase of the ASPEN high-altitude balloon campaign taking place in April and May 2023 is uniquely placed to make the first in-situ measurements of any earlier and enhanced polar stratospheric clouds expected due to the higher-than-usual stratospheric water vapour mixing ratios. We are continuing to interact with the University of Colorado team (Prof. Terry Deshler, Dr. Lars Kalnajs) and aim to compare simulations of the PSCs from the MeteorStrat project to these in-situ balloon measurements. The lead PI (Mann) and global aerosol modelling PDRA (Kamalika Sengupta) discussed with the NOAA and Univ. Denver project partners strategies for comparing the interactive stratospheric aerosol simulations to the two in-situ stratospheric aerosol measurement datasets. Dr. Dan Murphy visited Leeds in November 2019 and Prof. James C. Wilson visited Leeds in June 2019.
Collaborator Contribution Prof. Terry Deshler (Univ. Wyoming) is a project partner on the MeteorStrat project, and at the time the Leeds team were writing the MeteorStrat proposal, Prof. Deshler was preparing an NSF proposal seeking funding for two field campaign phases at McMurdo station in the Antarctic (in collaboration with Lars Kalnajs at NCAR, on high-altitude-balloon-borne condensation particle counter and optical particle counter measurements) which would measure at an unprecedented altitude (above 35km due new lightweight design, and during the autumn-winter period rather than the usual winter-spring period (usually selected due to monitoring of the ozone hole) The NSF research grant also involves Brian Toon's stratospheric aerosol and PSC modelling group at NCAR/Colorado Univ) to combine the measurements and modelling capabilities to interpret what the observations measure in the two autumn-winter seasons (Apr to Jun 2019 and Apr to Jun 2020). During his visit to Univ. Leeds in November 2019, Dr. Dan Murphy (Program Lead of the Aerosol Properties and Processes group, NOAA Chemical Services Division, Boulder, Colorado) contributed measurement datasets from the PALMS laser mass spectrometer instrument from multiple field campaigns, compiled into a form that enabled to compare with the interactive stratospheric aerosol simulations the Leeds global modelling PDRA (Kamalika Sengupta) has carried out for the project. During his visit to Univ. Leeds in June 2019, Prof. James C. Wilson (Dept. of Mechanical and Materials Engineering, Univ. Denver), discussed with the Leeds MeteorStrat team strategies for comparing to the database of high-altitude aerosol particle size distribution measurements (from multiple field campaigns sampling the lower stratosphere, including in the period after the 1991 Pinatubo eruption).
Impact Agreed contribution to science aligned to the Antarctic stratospheric aerosol NSF project, and to the NOAA and Univ. Denver stratospheric aerosol measurement datasets, and research papers are planned to compare the model simulations to these measurements, including the Apr-June 2019 McMurdo field campaign measurements, and/or the Hunga-Tonga-enhanced aerosol and PSCs in Apr-June 2023.
Start Year 2018
 
Description Collaboration with US research teams re: measurements of stratospheric aerosol 
Organisation University of Wyoming
Country United States 
Sector Academic/University 
PI Contribution At the Dec 2018 AGU fall meeting in Washington DC, Prof. Deshler, Dr. Kalnajs and Dr. Mann discussed the findings of the Leeds research team's UM-UKCA stratospheric aerosol model predictions, and invited Leeds to participate as an additional modelling activity aligned to the 2019 and 2020 field campaigns (see below). The Leeds MeteorStrat PI (Mann) joined the initial Skype planning meeting in January 2019 and explained the basis for how the Leeds team could contribute with initial simulations being run by the Leeds PDRA with work over the next 6-9 months to prepare for a bigger UK modelling contribution to the Apr-Jun 2020 campaign. Prof. Deshler originally planned to visit Leeds in September 2019 to share the data from the 1st phase campaign, and discuss the dedicated model experiments the Leeds team are running, to understand the progression of the meteoric-sulphuric particle abundance as the polar vortex forms and deepens through Antarctic autumn and into winter. With the Leeds SSiRC workshop scheduled for March 2020, and Dr. Kalnajs unavailable in Sept 2019, that visit was postponed to later in the project. The ASPEN field campaign 2nd phase was scheduled to take place in April to June 2020, with then Prof. Deshler planning to visit later in 2020. With the CoViD pandemic the 2nd phase of ASPEN had to be postponed, but was able to be re-scheduled to April-May 2023. Since the eruption of the Hunga-Tonga submarine volcanic eruption on 15th January 2022 the Southern Hemisphere stratosphere is experiencing very strongly enhanced concentrations of stratospheric water vapour, and although the stratospheric layer of enhanced water vapour remained outside the 2022 Antarctic vortex, since November 2022 the high-latitude Southern hemisphere stratosphere has much higher stratospheric water vapour than usual. This re-scheduled 2nd phase of the ASPEN high-altitude balloon campaign taking place in April and May 2023 is uniquely placed to make the first in-situ measurements of any earlier and enhanced polar stratospheric clouds expected due to the higher-than-usual stratospheric water vapour mixing ratios. We are continuing to interact with the University of Colorado team (Prof. Terry Deshler, Dr. Lars Kalnajs) and aim to compare simulations of the PSCs from the MeteorStrat project to these in-situ balloon measurements. The lead PI (Mann) and global aerosol modelling PDRA (Kamalika Sengupta) discussed with the NOAA and Univ. Denver project partners strategies for comparing the interactive stratospheric aerosol simulations to the two in-situ stratospheric aerosol measurement datasets. Dr. Dan Murphy visited Leeds in November 2019 and Prof. James C. Wilson visited Leeds in June 2019.
Collaborator Contribution Prof. Terry Deshler (Univ. Wyoming) is a project partner on the MeteorStrat project, and at the time the Leeds team were writing the MeteorStrat proposal, Prof. Deshler was preparing an NSF proposal seeking funding for two field campaign phases at McMurdo station in the Antarctic (in collaboration with Lars Kalnajs at NCAR, on high-altitude-balloon-borne condensation particle counter and optical particle counter measurements) which would measure at an unprecedented altitude (above 35km due new lightweight design, and during the autumn-winter period rather than the usual winter-spring period (usually selected due to monitoring of the ozone hole) The NSF research grant also involves Brian Toon's stratospheric aerosol and PSC modelling group at NCAR/Colorado Univ) to combine the measurements and modelling capabilities to interpret what the observations measure in the two autumn-winter seasons (Apr to Jun 2019 and Apr to Jun 2020). During his visit to Univ. Leeds in November 2019, Dr. Dan Murphy (Program Lead of the Aerosol Properties and Processes group, NOAA Chemical Services Division, Boulder, Colorado) contributed measurement datasets from the PALMS laser mass spectrometer instrument from multiple field campaigns, compiled into a form that enabled to compare with the interactive stratospheric aerosol simulations the Leeds global modelling PDRA (Kamalika Sengupta) has carried out for the project. During his visit to Univ. Leeds in June 2019, Prof. James C. Wilson (Dept. of Mechanical and Materials Engineering, Univ. Denver), discussed with the Leeds MeteorStrat team strategies for comparing to the database of high-altitude aerosol particle size distribution measurements (from multiple field campaigns sampling the lower stratosphere, including in the period after the 1991 Pinatubo eruption).
Impact Agreed contribution to science aligned to the Antarctic stratospheric aerosol NSF project, and to the NOAA and Univ. Denver stratospheric aerosol measurement datasets, and research papers are planned to compare the model simulations to these measurements, including the Apr-June 2019 McMurdo field campaign measurements, and/or the Hunga-Tonga-enhanced aerosol and PSCs in Apr-June 2023.
Start Year 2018
 
Description Leeds completed integration of meteoric-sulphuric model capability into stratosphere-troposphere aerosol modelling component of European "Copernicus" atmospheric monitoring programme 
Organisation Belgian Institute for Space Aeronomy
Country Belgium 
Sector Public 
PI Contribution The Leeds research team (PI Mann) have collaborated with several other international groups (Olivier Boucher, Sam Remy, CNRS Paris, Vincent Huijnen, KNMI, Simon Chabrillat, BIRA Brussels, Johannes Flemming, Zak Kipling, ECMWF) to develop an interactive stratosphere-troposphere aerosol capability within the global modelling component of the flagship European atmospheric monitoring programme Copernicus, during its 2nd phase (Apr 2019 to Mar 2022). During the 1st phase of the Copernicus Atmospheric Monitoring Service (CAMS), from Apr 2016 to Mar 2019, the Leeds aerosol microphysics module GLOMAP-mode (already a core component of the joint NERC-Met Office UK Earth System Model) was validated in the pre-operational Composition-IFS system (independently by the CNRS and Met Norway groups) in advance of the switch-over from the mass-based aerosol scheme currently being applied for operational global aerosol forecasts and re-analyses. During the 2nd phase of the CAMS global aerosol development consortium tender (CAMS43), the Leeds team, led by MeteorStrat PI Mann, have completed, in collaboration with BIRA-Brussels, KNMI-Utrecht and CNRS-Paris, two strands of activity around stratospheric aerosol layer modelling, the 1st to improve simulations of the quiescent (background) aerosol layer, resolving both pure sulphuric and meteoric-sulphuric aerosol particles within the ECMWF modelling system. During 2020, this 2nd phase CAMS43 has now replicated in the European modelling system the same meteoric-sulphuric capability developed within GA4 UM-UKCA in 2015/2016 (e.g. Brooke et al., JGR, 2017) during the European Research Council large grant project "Cosmic Dust In The Atmosphere" (CODITA). During 1st phase CAMS43, Leeds already contributed model "initialisation fields" from major volcanic aerosol simulations from this same meteoric-sulphuric capability, which the group carried out in 2017/2018 within the interactive stratospheric aerosol configuration of the UK's composition-climate model UM-UKCA. Those simulations are based on a "what-if" major eruption scenario for how the minor Agung eruption in October 2017 could have progressed. The experiments essentially scale-up from 1963 event (about half the sulphur from 1991 Pinatubo) to a Tambora-scale event (approximately 10 times the sulphur from the 1963 Agung event). The initialisation fields from the Pinatubo-magnitude volcanic aerosol simulations were applied in the European Composition-IFS system to enact the same scenarios within the weeks-to-months timescale the Integrated Forecasting System is designed to predict for. The collaboration originated from discussions at the 2016 CAMS assembly in Athens, a new synthesis activity between the Global Aerosol and Global Reactive Gases consortium projects within CAMS. The team essentially agreed to, as an element not originally planned within 1st phase of CAMS, to combine the interactive stratospheric aerosol and interactive stratospheric ozone modelling capabilities they had produced separately. Several deliverable reports describing the volcanic aerosol capability were completed in 2019 and 2020, which could then be deployed to predict the global dispersion of a future major eruption cloud. The meteoric-sulphuric capability was added to the system in 2020, and documented in quiescent conditions in the 1st strat-aerosol deliverable report in 2nd phase CAMS43 (February 2021), fully approved by ECMWF. The interaction effects were active also within a set of major volcanic aerosol simulations around a case study of Pinatubo, this the topic of the 2nd strat-aerosol deliverable report in 2hd phase CAMS43 (June 2021), compared to Mauna Loa ground-based lidar measurements, to aircraft-borne lidar measurements from the NASA survey mission in July 1991, and to the UM-UKCA interactive aerosol Pinatubo simulations from Dhomse et al. (ACP, 2020) and those from the joint CAMS-Leeds PhD studentship (Dr. Sarah Shallcross). A 3rd ECMWF-approved CAMS stratospheric aerosol deliverable report, from additional collaboration within July and August 2021 analysed the effect of the meteoric-sulphuric interactions in the ECMWF-IFS system, within a extension to the 2nd phase CAMS43 project, the report approved by ECMWF in September 2021.
Collaborator Contribution The CNRS modelling group ran simulations of the Holhuraun eruption (Iceland) and Calbuco eruption (Chile) and the additional what-if scenario for the October 2017 minor eruption of Mt Agung (Bali) progressing to major eruption on the scale of the 1963 event (and larger). The KNMI scientist (Huijnen) contributed the stratospheric chemistry modelling, adding sulphur chemistry following the reaction-set the Leeds group implemented in the UK model (see Dhomse et al. 2014). The BIRA scientist (Chabrillat) contributed improvements to the representation of the photolysis cross-sections for the gas phase sulphur species in the Dhomse14 scheme and advised KNMI on the stratospheric chemistry developments. KNMI joined the CAMS aerosol consortium for the 2nd phase of CAMS43 (Apr 2019 to Mar 2022), the co-operation continuing also on the chemistry side to pick up interactive aerosol surface area, then enabling stratospheric ozone loss to include to predict including the heterogeneous reactions that would occur within the evolving volcanic aerosol cloud.
Impact Peer-reviewed journal publications are planned during 2nd phase CAMS43 reporting the results from predictions with the Composition-IFS volcanic aerosol forecasting system, and re: the quiescent stratospheric aerosol layer (incorporating the meteoric-sulphuric particles). With the GLOMAP system now validated to become the aerosol scheme for the operational CAMS global aerosol forecasting and re-analysis system (co-ordinated by the European Centre for Medium-Range Weather Forecasting), there are likely to be a range of important impacts arising from this progression in capability in the coming years.
Start Year 2018
 
Description Leeds completed integration of meteoric-sulphuric model capability into stratosphere-troposphere aerosol modelling component of European "Copernicus" atmospheric monitoring programme 
Organisation European Union
Department Comenius
Country European Union (EU) 
Sector Public 
PI Contribution The Leeds research team (PI Mann) have collaborated with several other international groups (Olivier Boucher, Sam Remy, CNRS Paris, Vincent Huijnen, KNMI, Simon Chabrillat, BIRA Brussels, Johannes Flemming, Zak Kipling, ECMWF) to develop an interactive stratosphere-troposphere aerosol capability within the global modelling component of the flagship European atmospheric monitoring programme Copernicus, during its 2nd phase (Apr 2019 to Mar 2022). During the 1st phase of the Copernicus Atmospheric Monitoring Service (CAMS), from Apr 2016 to Mar 2019, the Leeds aerosol microphysics module GLOMAP-mode (already a core component of the joint NERC-Met Office UK Earth System Model) was validated in the pre-operational Composition-IFS system (independently by the CNRS and Met Norway groups) in advance of the switch-over from the mass-based aerosol scheme currently being applied for operational global aerosol forecasts and re-analyses. During the 2nd phase of the CAMS global aerosol development consortium tender (CAMS43), the Leeds team, led by MeteorStrat PI Mann, have completed, in collaboration with BIRA-Brussels, KNMI-Utrecht and CNRS-Paris, two strands of activity around stratospheric aerosol layer modelling, the 1st to improve simulations of the quiescent (background) aerosol layer, resolving both pure sulphuric and meteoric-sulphuric aerosol particles within the ECMWF modelling system. During 2020, this 2nd phase CAMS43 has now replicated in the European modelling system the same meteoric-sulphuric capability developed within GA4 UM-UKCA in 2015/2016 (e.g. Brooke et al., JGR, 2017) during the European Research Council large grant project "Cosmic Dust In The Atmosphere" (CODITA). During 1st phase CAMS43, Leeds already contributed model "initialisation fields" from major volcanic aerosol simulations from this same meteoric-sulphuric capability, which the group carried out in 2017/2018 within the interactive stratospheric aerosol configuration of the UK's composition-climate model UM-UKCA. Those simulations are based on a "what-if" major eruption scenario for how the minor Agung eruption in October 2017 could have progressed. The experiments essentially scale-up from 1963 event (about half the sulphur from 1991 Pinatubo) to a Tambora-scale event (approximately 10 times the sulphur from the 1963 Agung event). The initialisation fields from the Pinatubo-magnitude volcanic aerosol simulations were applied in the European Composition-IFS system to enact the same scenarios within the weeks-to-months timescale the Integrated Forecasting System is designed to predict for. The collaboration originated from discussions at the 2016 CAMS assembly in Athens, a new synthesis activity between the Global Aerosol and Global Reactive Gases consortium projects within CAMS. The team essentially agreed to, as an element not originally planned within 1st phase of CAMS, to combine the interactive stratospheric aerosol and interactive stratospheric ozone modelling capabilities they had produced separately. Several deliverable reports describing the volcanic aerosol capability were completed in 2019 and 2020, which could then be deployed to predict the global dispersion of a future major eruption cloud. The meteoric-sulphuric capability was added to the system in 2020, and documented in quiescent conditions in the 1st strat-aerosol deliverable report in 2nd phase CAMS43 (February 2021), fully approved by ECMWF. The interaction effects were active also within a set of major volcanic aerosol simulations around a case study of Pinatubo, this the topic of the 2nd strat-aerosol deliverable report in 2hd phase CAMS43 (June 2021), compared to Mauna Loa ground-based lidar measurements, to aircraft-borne lidar measurements from the NASA survey mission in July 1991, and to the UM-UKCA interactive aerosol Pinatubo simulations from Dhomse et al. (ACP, 2020) and those from the joint CAMS-Leeds PhD studentship (Dr. Sarah Shallcross). A 3rd ECMWF-approved CAMS stratospheric aerosol deliverable report, from additional collaboration within July and August 2021 analysed the effect of the meteoric-sulphuric interactions in the ECMWF-IFS system, within a extension to the 2nd phase CAMS43 project, the report approved by ECMWF in September 2021.
Collaborator Contribution The CNRS modelling group ran simulations of the Holhuraun eruption (Iceland) and Calbuco eruption (Chile) and the additional what-if scenario for the October 2017 minor eruption of Mt Agung (Bali) progressing to major eruption on the scale of the 1963 event (and larger). The KNMI scientist (Huijnen) contributed the stratospheric chemistry modelling, adding sulphur chemistry following the reaction-set the Leeds group implemented in the UK model (see Dhomse et al. 2014). The BIRA scientist (Chabrillat) contributed improvements to the representation of the photolysis cross-sections for the gas phase sulphur species in the Dhomse14 scheme and advised KNMI on the stratospheric chemistry developments. KNMI joined the CAMS aerosol consortium for the 2nd phase of CAMS43 (Apr 2019 to Mar 2022), the co-operation continuing also on the chemistry side to pick up interactive aerosol surface area, then enabling stratospheric ozone loss to include to predict including the heterogeneous reactions that would occur within the evolving volcanic aerosol cloud.
Impact Peer-reviewed journal publications are planned during 2nd phase CAMS43 reporting the results from predictions with the Composition-IFS volcanic aerosol forecasting system, and re: the quiescent stratospheric aerosol layer (incorporating the meteoric-sulphuric particles). With the GLOMAP system now validated to become the aerosol scheme for the operational CAMS global aerosol forecasting and re-analysis system (co-ordinated by the European Centre for Medium-Range Weather Forecasting), there are likely to be a range of important impacts arising from this progression in capability in the coming years.
Start Year 2018
 
Description Leeds completed integration of meteoric-sulphuric model capability into stratosphere-troposphere aerosol modelling component of European "Copernicus" atmospheric monitoring programme 
Organisation National Center for Scientific Research (Centre National de la Recherche Scientifique CNRS)
Country France 
Sector Academic/University 
PI Contribution The Leeds research team (PI Mann) have collaborated with several other international groups (Olivier Boucher, Sam Remy, CNRS Paris, Vincent Huijnen, KNMI, Simon Chabrillat, BIRA Brussels, Johannes Flemming, Zak Kipling, ECMWF) to develop an interactive stratosphere-troposphere aerosol capability within the global modelling component of the flagship European atmospheric monitoring programme Copernicus, during its 2nd phase (Apr 2019 to Mar 2022). During the 1st phase of the Copernicus Atmospheric Monitoring Service (CAMS), from Apr 2016 to Mar 2019, the Leeds aerosol microphysics module GLOMAP-mode (already a core component of the joint NERC-Met Office UK Earth System Model) was validated in the pre-operational Composition-IFS system (independently by the CNRS and Met Norway groups) in advance of the switch-over from the mass-based aerosol scheme currently being applied for operational global aerosol forecasts and re-analyses. During the 2nd phase of the CAMS global aerosol development consortium tender (CAMS43), the Leeds team, led by MeteorStrat PI Mann, have completed, in collaboration with BIRA-Brussels, KNMI-Utrecht and CNRS-Paris, two strands of activity around stratospheric aerosol layer modelling, the 1st to improve simulations of the quiescent (background) aerosol layer, resolving both pure sulphuric and meteoric-sulphuric aerosol particles within the ECMWF modelling system. During 2020, this 2nd phase CAMS43 has now replicated in the European modelling system the same meteoric-sulphuric capability developed within GA4 UM-UKCA in 2015/2016 (e.g. Brooke et al., JGR, 2017) during the European Research Council large grant project "Cosmic Dust In The Atmosphere" (CODITA). During 1st phase CAMS43, Leeds already contributed model "initialisation fields" from major volcanic aerosol simulations from this same meteoric-sulphuric capability, which the group carried out in 2017/2018 within the interactive stratospheric aerosol configuration of the UK's composition-climate model UM-UKCA. Those simulations are based on a "what-if" major eruption scenario for how the minor Agung eruption in October 2017 could have progressed. The experiments essentially scale-up from 1963 event (about half the sulphur from 1991 Pinatubo) to a Tambora-scale event (approximately 10 times the sulphur from the 1963 Agung event). The initialisation fields from the Pinatubo-magnitude volcanic aerosol simulations were applied in the European Composition-IFS system to enact the same scenarios within the weeks-to-months timescale the Integrated Forecasting System is designed to predict for. The collaboration originated from discussions at the 2016 CAMS assembly in Athens, a new synthesis activity between the Global Aerosol and Global Reactive Gases consortium projects within CAMS. The team essentially agreed to, as an element not originally planned within 1st phase of CAMS, to combine the interactive stratospheric aerosol and interactive stratospheric ozone modelling capabilities they had produced separately. Several deliverable reports describing the volcanic aerosol capability were completed in 2019 and 2020, which could then be deployed to predict the global dispersion of a future major eruption cloud. The meteoric-sulphuric capability was added to the system in 2020, and documented in quiescent conditions in the 1st strat-aerosol deliverable report in 2nd phase CAMS43 (February 2021), fully approved by ECMWF. The interaction effects were active also within a set of major volcanic aerosol simulations around a case study of Pinatubo, this the topic of the 2nd strat-aerosol deliverable report in 2hd phase CAMS43 (June 2021), compared to Mauna Loa ground-based lidar measurements, to aircraft-borne lidar measurements from the NASA survey mission in July 1991, and to the UM-UKCA interactive aerosol Pinatubo simulations from Dhomse et al. (ACP, 2020) and those from the joint CAMS-Leeds PhD studentship (Dr. Sarah Shallcross). A 3rd ECMWF-approved CAMS stratospheric aerosol deliverable report, from additional collaboration within July and August 2021 analysed the effect of the meteoric-sulphuric interactions in the ECMWF-IFS system, within a extension to the 2nd phase CAMS43 project, the report approved by ECMWF in September 2021.
Collaborator Contribution The CNRS modelling group ran simulations of the Holhuraun eruption (Iceland) and Calbuco eruption (Chile) and the additional what-if scenario for the October 2017 minor eruption of Mt Agung (Bali) progressing to major eruption on the scale of the 1963 event (and larger). The KNMI scientist (Huijnen) contributed the stratospheric chemistry modelling, adding sulphur chemistry following the reaction-set the Leeds group implemented in the UK model (see Dhomse et al. 2014). The BIRA scientist (Chabrillat) contributed improvements to the representation of the photolysis cross-sections for the gas phase sulphur species in the Dhomse14 scheme and advised KNMI on the stratospheric chemistry developments. KNMI joined the CAMS aerosol consortium for the 2nd phase of CAMS43 (Apr 2019 to Mar 2022), the co-operation continuing also on the chemistry side to pick up interactive aerosol surface area, then enabling stratospheric ozone loss to include to predict including the heterogeneous reactions that would occur within the evolving volcanic aerosol cloud.
Impact Peer-reviewed journal publications are planned during 2nd phase CAMS43 reporting the results from predictions with the Composition-IFS volcanic aerosol forecasting system, and re: the quiescent stratospheric aerosol layer (incorporating the meteoric-sulphuric particles). With the GLOMAP system now validated to become the aerosol scheme for the operational CAMS global aerosol forecasting and re-analysis system (co-ordinated by the European Centre for Medium-Range Weather Forecasting), there are likely to be a range of important impacts arising from this progression in capability in the coming years.
Start Year 2018
 
Description Leeds completed integration of meteoric-sulphuric model capability into stratosphere-troposphere aerosol modelling component of European "Copernicus" atmospheric monitoring programme 
Organisation Royal Netherlands Meteorological Institute
Country Netherlands 
Sector Academic/University 
PI Contribution The Leeds research team (PI Mann) have collaborated with several other international groups (Olivier Boucher, Sam Remy, CNRS Paris, Vincent Huijnen, KNMI, Simon Chabrillat, BIRA Brussels, Johannes Flemming, Zak Kipling, ECMWF) to develop an interactive stratosphere-troposphere aerosol capability within the global modelling component of the flagship European atmospheric monitoring programme Copernicus, during its 2nd phase (Apr 2019 to Mar 2022). During the 1st phase of the Copernicus Atmospheric Monitoring Service (CAMS), from Apr 2016 to Mar 2019, the Leeds aerosol microphysics module GLOMAP-mode (already a core component of the joint NERC-Met Office UK Earth System Model) was validated in the pre-operational Composition-IFS system (independently by the CNRS and Met Norway groups) in advance of the switch-over from the mass-based aerosol scheme currently being applied for operational global aerosol forecasts and re-analyses. During the 2nd phase of the CAMS global aerosol development consortium tender (CAMS43), the Leeds team, led by MeteorStrat PI Mann, have completed, in collaboration with BIRA-Brussels, KNMI-Utrecht and CNRS-Paris, two strands of activity around stratospheric aerosol layer modelling, the 1st to improve simulations of the quiescent (background) aerosol layer, resolving both pure sulphuric and meteoric-sulphuric aerosol particles within the ECMWF modelling system. During 2020, this 2nd phase CAMS43 has now replicated in the European modelling system the same meteoric-sulphuric capability developed within GA4 UM-UKCA in 2015/2016 (e.g. Brooke et al., JGR, 2017) during the European Research Council large grant project "Cosmic Dust In The Atmosphere" (CODITA). During 1st phase CAMS43, Leeds already contributed model "initialisation fields" from major volcanic aerosol simulations from this same meteoric-sulphuric capability, which the group carried out in 2017/2018 within the interactive stratospheric aerosol configuration of the UK's composition-climate model UM-UKCA. Those simulations are based on a "what-if" major eruption scenario for how the minor Agung eruption in October 2017 could have progressed. The experiments essentially scale-up from 1963 event (about half the sulphur from 1991 Pinatubo) to a Tambora-scale event (approximately 10 times the sulphur from the 1963 Agung event). The initialisation fields from the Pinatubo-magnitude volcanic aerosol simulations were applied in the European Composition-IFS system to enact the same scenarios within the weeks-to-months timescale the Integrated Forecasting System is designed to predict for. The collaboration originated from discussions at the 2016 CAMS assembly in Athens, a new synthesis activity between the Global Aerosol and Global Reactive Gases consortium projects within CAMS. The team essentially agreed to, as an element not originally planned within 1st phase of CAMS, to combine the interactive stratospheric aerosol and interactive stratospheric ozone modelling capabilities they had produced separately. Several deliverable reports describing the volcanic aerosol capability were completed in 2019 and 2020, which could then be deployed to predict the global dispersion of a future major eruption cloud. The meteoric-sulphuric capability was added to the system in 2020, and documented in quiescent conditions in the 1st strat-aerosol deliverable report in 2nd phase CAMS43 (February 2021), fully approved by ECMWF. The interaction effects were active also within a set of major volcanic aerosol simulations around a case study of Pinatubo, this the topic of the 2nd strat-aerosol deliverable report in 2hd phase CAMS43 (June 2021), compared to Mauna Loa ground-based lidar measurements, to aircraft-borne lidar measurements from the NASA survey mission in July 1991, and to the UM-UKCA interactive aerosol Pinatubo simulations from Dhomse et al. (ACP, 2020) and those from the joint CAMS-Leeds PhD studentship (Dr. Sarah Shallcross). A 3rd ECMWF-approved CAMS stratospheric aerosol deliverable report, from additional collaboration within July and August 2021 analysed the effect of the meteoric-sulphuric interactions in the ECMWF-IFS system, within a extension to the 2nd phase CAMS43 project, the report approved by ECMWF in September 2021.
Collaborator Contribution The CNRS modelling group ran simulations of the Holhuraun eruption (Iceland) and Calbuco eruption (Chile) and the additional what-if scenario for the October 2017 minor eruption of Mt Agung (Bali) progressing to major eruption on the scale of the 1963 event (and larger). The KNMI scientist (Huijnen) contributed the stratospheric chemistry modelling, adding sulphur chemistry following the reaction-set the Leeds group implemented in the UK model (see Dhomse et al. 2014). The BIRA scientist (Chabrillat) contributed improvements to the representation of the photolysis cross-sections for the gas phase sulphur species in the Dhomse14 scheme and advised KNMI on the stratospheric chemistry developments. KNMI joined the CAMS aerosol consortium for the 2nd phase of CAMS43 (Apr 2019 to Mar 2022), the co-operation continuing also on the chemistry side to pick up interactive aerosol surface area, then enabling stratospheric ozone loss to include to predict including the heterogeneous reactions that would occur within the evolving volcanic aerosol cloud.
Impact Peer-reviewed journal publications are planned during 2nd phase CAMS43 reporting the results from predictions with the Composition-IFS volcanic aerosol forecasting system, and re: the quiescent stratospheric aerosol layer (incorporating the meteoric-sulphuric particles). With the GLOMAP system now validated to become the aerosol scheme for the operational CAMS global aerosol forecasting and re-analysis system (co-ordinated by the European Centre for Medium-Range Weather Forecasting), there are likely to be a range of important impacts arising from this progression in capability in the coming years.
Start Year 2018
 
Description Leeds hosted May 2022 international workshop on stratospheric aerosol layer (WCRP activity on "Stratospheric Sulfur and its Role in Climate") 
Organisation National Aeronautics and Space Administration (NASA)
Department NASA Langley Research Centre
Country United States 
Sector Public 
PI Contribution The Univ. Leeds MeteorStrat PI (Dr. Graham Mann) is on the Scientific Steering Committee of the WCRP-SPARC initiative on stratospheric sulphur (SSiRC) and is leading the organisation of the SSiRC workshop, with the Univ. Leeds MeteorStrat global modelling PDRA and the University of Leeds MeetInLeeds conference team (Corin Nanton and Anthony Lowe). Unfortunately, although 60+ Abstracts were submitted to the Leeds SSiRC workshop, scheduled for March 2020, with the ensuing global pandemic, the workshop had to be postponed. An original re-scheduling of the workshop to 22nd-24th April 2021 then had to be further postponed (with the 3rd wave in December and January). The re-scheduled Leeds SSiRC workshop took place at the University of Leeds from Tue 16th to Thu 18th May 2022, with ~60 Abstracts submitted -- see https://eu.eventscloud.com/ehome/200197691/programme/ A follow-on half-day MeteorStrat outreach workshop took place after the SSiRC workshop, to showcase the science in the project to the UK atmospheric science community, and also explain its relevance to the international scientists attending the SSiRC workshop.
Collaborator Contribution Dr. Larry Thomason (NASA Langley) is the overall lead for the SSiRC and a project partner on MeteorStrat and co-leading the organisation of the SSiRC workshop with MeteorStrat PI Dr. Graham Mann. Applications to NASA and WCRP-SPARC for sponsoring the workshop, to provide travel funding for Early Career Researchers to travel to the workshop, prioritising those scientists travelling from the Global South.
Impact Over 60 Abstracts were submitted to international workshop May 16th to May 18th 2022, with a half-day UK-science-facing outreach workshop for MeteorStrat (as set out in the proposal Justification of Resources) taking place after the SSiRC workshop (Friday May 20th 2022).
Start Year 2019
 
Description MeteorStrat PI co-leading international modelling activity for interactive stratospheric aerosol models (ISA-MIP) 
Organisation American University
Country United States 
Sector Academic/University 
PI Contribution The MeteorStrat PI (Dr. Graham Mann) is leading the international stratospheric aerosol modelling activity "ISA-MIP", and one of the 4 co-ordinated modelling experiments focusses on the background stratospheric aerosol layer (BG experiment), where meteoric particles strongly affect the properties of the stratospheric aerosol layer. The BG experiment will include only 1 other model similar to the UM-UKCA community model which include meteoric-sulphuric aerosol particles in their predictions, the other models simulating only pure sulphuric aerosol particles. The inter comparison aligns closely with the science in MeteorStrat and gives an international dimension to the WP2 stratospheric aerosol modelling activities. Within the activity for the August 2021 report of the CAMS43 phase 2 (ECMWF and European partner collaboration activity) the ICBG system was run for a benchmark 5-year integration for the quiescent period 1998-2002, for submission to the ISA-MIP BG experiment (then a third model in ISA-MIP including meteoric-sulphuric interactions). Since June 2022, Dr. Timofei Sukhodolov (Davos PMOD/JRC, Switzerland) Since September 2022,
Collaborator Contribution Dr. Claudia Timmreck (Max Planck Institute for Meteorology, Hamburg.), project partner on MeteorStrat, was the original co-lead of ISA-MIP with Dr. Graham Mann (MeteorStrat PI). Dr. Timmreck and the MeteorStrat PI Dr. Mann co-led the 2018 Geoscientific Model Development article that sets out the rationale for the ISA-MIP experiments, in collaboration with a range of internationally-leading scientists. Dr. Valentina Aquila (American University, Washington DC, USA; formerly NASA Goddard Space Flight Center) took over from Dr. Timmreck in 2019 as ISA-MIP co-lead, and co-lead ISA-MIP in the "submission phase", 2019-2022. Dr. Timofei Sukhodolov (Davos PMOD/JRC, Switzerland) took over from Dr. Aquila as ISA-MIP co-lead, and is supervising a Masters of Research student at ETH Zurich (Christina Brodowsky) whose MRes project is analysing the quiescent stratospheric aerosol properties simulated by the ~5 models that have submitted data to the BG experiment within ISA-MIP (including UM-UKCA). A PhD student co-supervised by Dr. Timmreck (Ilaria Quaglia) carried out a multi-model analysis of the ISA-MIP HErSEA interactive stratospheric aerosol simulations of the Pinatubo volcanic aerosol cloud, and published a paper in January 2023 in this ISA-MIP HErSEA analysis within the international peer-reviewed journal Atmospheric Chemistry and Physics.
Impact 2018 Geoscientific Model Development paper describing the rationale and specifications of the ISA-MIP co-ordinated experiments.
Start Year 2018
 
Description MeteorStrat PI co-leading international modelling activity for interactive stratospheric aerosol models (ISA-MIP) 
Organisation Max Planck Institute for Meteorology
Country Germany 
Sector Public 
PI Contribution The MeteorStrat PI (Dr. Graham Mann) is leading the international stratospheric aerosol modelling activity "ISA-MIP", and one of the 4 co-ordinated modelling experiments focusses on the background stratospheric aerosol layer (BG experiment), where meteoric particles strongly affect the properties of the stratospheric aerosol layer. The BG experiment will include only 1 other model similar to the UM-UKCA community model which include meteoric-sulphuric aerosol particles in their predictions, the other models simulating only pure sulphuric aerosol particles. The inter comparison aligns closely with the science in MeteorStrat and gives an international dimension to the WP2 stratospheric aerosol modelling activities. Within the activity for the August 2021 report of the CAMS43 phase 2 (ECMWF and European partner collaboration activity) the ICBG system was run for a benchmark 5-year integration for the quiescent period 1998-2002, for submission to the ISA-MIP BG experiment (then a third model in ISA-MIP including meteoric-sulphuric interactions). Since June 2022, Dr. Timofei Sukhodolov (Davos PMOD/JRC, Switzerland) Since September 2022,
Collaborator Contribution Dr. Claudia Timmreck (Max Planck Institute for Meteorology, Hamburg.), project partner on MeteorStrat, was the original co-lead of ISA-MIP with Dr. Graham Mann (MeteorStrat PI). Dr. Timmreck and the MeteorStrat PI Dr. Mann co-led the 2018 Geoscientific Model Development article that sets out the rationale for the ISA-MIP experiments, in collaboration with a range of internationally-leading scientists. Dr. Valentina Aquila (American University, Washington DC, USA; formerly NASA Goddard Space Flight Center) took over from Dr. Timmreck in 2019 as ISA-MIP co-lead, and co-lead ISA-MIP in the "submission phase", 2019-2022. Dr. Timofei Sukhodolov (Davos PMOD/JRC, Switzerland) took over from Dr. Aquila as ISA-MIP co-lead, and is supervising a Masters of Research student at ETH Zurich (Christina Brodowsky) whose MRes project is analysing the quiescent stratospheric aerosol properties simulated by the ~5 models that have submitted data to the BG experiment within ISA-MIP (including UM-UKCA). A PhD student co-supervised by Dr. Timmreck (Ilaria Quaglia) carried out a multi-model analysis of the ISA-MIP HErSEA interactive stratospheric aerosol simulations of the Pinatubo volcanic aerosol cloud, and published a paper in January 2023 in this ISA-MIP HErSEA analysis within the international peer-reviewed journal Atmospheric Chemistry and Physics.
Impact 2018 Geoscientific Model Development paper describing the rationale and specifications of the ISA-MIP co-ordinated experiments.
Start Year 2018
 
Description MeteorStrat PI co-leading international modelling activity for interactive stratospheric aerosol models (ISA-MIP) 
Organisation The Physikalisch-Meteorologisches Observatorium Davos/World Radiation Center
Country Switzerland 
Sector Academic/University 
PI Contribution The MeteorStrat PI (Dr. Graham Mann) is leading the international stratospheric aerosol modelling activity "ISA-MIP", and one of the 4 co-ordinated modelling experiments focusses on the background stratospheric aerosol layer (BG experiment), where meteoric particles strongly affect the properties of the stratospheric aerosol layer. The BG experiment will include only 1 other model similar to the UM-UKCA community model which include meteoric-sulphuric aerosol particles in their predictions, the other models simulating only pure sulphuric aerosol particles. The inter comparison aligns closely with the science in MeteorStrat and gives an international dimension to the WP2 stratospheric aerosol modelling activities. Within the activity for the August 2021 report of the CAMS43 phase 2 (ECMWF and European partner collaboration activity) the ICBG system was run for a benchmark 5-year integration for the quiescent period 1998-2002, for submission to the ISA-MIP BG experiment (then a third model in ISA-MIP including meteoric-sulphuric interactions). Since June 2022, Dr. Timofei Sukhodolov (Davos PMOD/JRC, Switzerland) Since September 2022,
Collaborator Contribution Dr. Claudia Timmreck (Max Planck Institute for Meteorology, Hamburg.), project partner on MeteorStrat, was the original co-lead of ISA-MIP with Dr. Graham Mann (MeteorStrat PI). Dr. Timmreck and the MeteorStrat PI Dr. Mann co-led the 2018 Geoscientific Model Development article that sets out the rationale for the ISA-MIP experiments, in collaboration with a range of internationally-leading scientists. Dr. Valentina Aquila (American University, Washington DC, USA; formerly NASA Goddard Space Flight Center) took over from Dr. Timmreck in 2019 as ISA-MIP co-lead, and co-lead ISA-MIP in the "submission phase", 2019-2022. Dr. Timofei Sukhodolov (Davos PMOD/JRC, Switzerland) took over from Dr. Aquila as ISA-MIP co-lead, and is supervising a Masters of Research student at ETH Zurich (Christina Brodowsky) whose MRes project is analysing the quiescent stratospheric aerosol properties simulated by the ~5 models that have submitted data to the BG experiment within ISA-MIP (including UM-UKCA). A PhD student co-supervised by Dr. Timmreck (Ilaria Quaglia) carried out a multi-model analysis of the ISA-MIP HErSEA interactive stratospheric aerosol simulations of the Pinatubo volcanic aerosol cloud, and published a paper in January 2023 in this ISA-MIP HErSEA analysis within the international peer-reviewed journal Atmospheric Chemistry and Physics.
Impact 2018 Geoscientific Model Development paper describing the rationale and specifications of the ISA-MIP co-ordinated experiments.
Start Year 2018
 
Description UK-China co-operation on UKESM re: climate and ozone layer impacts from 2022 Hunga eruption 
Organisation Chengdu University
Country China 
Sector Academic/University 
PI Contribution MeteorStrat PI Mann is one of four scientists on the leadership team of the 2023-2025 SPARC cross-activity focus project on Hunga-Tonga. MeteorStrat PI Mann and MeteorStrat co-I Feng co-configured, analysed and submitted the UKESM1 volc-pinatubo-full climate model simulation data which Dr. Zhou analysed for the post-Pinatubo stratospheric water vapour GRL paper, including finalising the UKESM1 submission of the VolMIP simulations to the CMIP6 archive on CEDA. The increases in stratospheric water vapour after volcanic eruptions is a recognised uncertainty in volcanic impacts on climate, and a key focus area for current research, with the 2022 and 2023 stratosphere strongly enhanced in water vapour from the direct emission of water vapour from the large-magnitude explosive eruption of the Hunga volcano in January 2022. Dr. Zhou's two-year visiting scientist role at Leeds ended in December 2023, and the team have applied for funding via the Royal Society UK-China initiative, to progress the UK-China collaboration also with Univ. Edinburgh Dr. Hugh Pumphrey, re: satellite measurements of the enhanced water vapour. Dr. Mann and Dr. Zhou have also agreed to co-lead the UKESM1 submissions to a new "Hunga-Tonga Model-Observation Comparison" MIP activity (HT-MOC) focused towards predicting the longevity of the stratospheric water vapour enhancement from the eruption, and its impacts on polar ozone. A CASE studentship with the UK Met Office has begun in October 2023, directly aligned to this continuing Leeds-Chengdu collaboration on the Hunga impacts on the stratospheric ozone layer
Collaborator Contribution Dr. Xin Zhou (lecturer in atmospheric science, Chengdu University) visited University of Leeds during 2020-2022, hosted by MeteorStrat co-Is Prof. Martyn Chipperfield and Dr. Wuhu Feng. Dr. Zhou's research analyses the influence of tropical ocean variability (El Nino Southern Oscillation, ENSO) on upwelling in the stratosphere, and the main area of collaboration aligned to the MeteorStrat science is re: volcanic impacts on climate and the stratospheric ozone layer. Dr. Zhou's analysis focused specifically on the UKESM1 simulated increase in stratospheric water vapour across the 27-member ensemble, showing that ENSO phase strongly modulates the post-eruption stratospheric increase in water vapour.
Impact Zhou, X., Mann, G. W., Feng, W., Dhomse, S. S., & Chipperfield, M. P. (2023). The influence of internal climate variability on stratospheric water vapor increases after large-magnitude explosive tropical volcanic eruptions. Geophysical Research Letters, 50, e2023GL103076. https://doi.org/10.1029/2023GL103076
Start Year 2021
 
Description UK-China co-operation on UKESM re: climate and ozone layer impacts from 2022 Hunga eruption 
Organisation Chengdu University of Technology
Department State Key Laboratory of Geohazard Prevention and Geoenvironmental Protection
Country China 
Sector Academic/University 
PI Contribution MeteorStrat PI Mann is one of four scientists on the leadership team of the 2023-2025 SPARC cross-activity focus project on Hunga-Tonga. MeteorStrat PI Mann and MeteorStrat co-I Feng co-configured, analysed and submitted the UKESM1 volc-pinatubo-full climate model simulation data which Dr. Zhou analysed for the post-Pinatubo stratospheric water vapour GRL paper, including finalising the UKESM1 submission of the VolMIP simulations to the CMIP6 archive on CEDA. The increases in stratospheric water vapour after volcanic eruptions is a recognised uncertainty in volcanic impacts on climate, and a key focus area for current research, with the 2022 and 2023 stratosphere strongly enhanced in water vapour from the direct emission of water vapour from the large-magnitude explosive eruption of the Hunga volcano in January 2022. Dr. Zhou's two-year visiting scientist role at Leeds ended in December 2023, and the team have applied for funding via the Royal Society UK-China initiative, to progress the UK-China collaboration also with Univ. Edinburgh Dr. Hugh Pumphrey, re: satellite measurements of the enhanced water vapour. Dr. Mann and Dr. Zhou have also agreed to co-lead the UKESM1 submissions to a new "Hunga-Tonga Model-Observation Comparison" MIP activity (HT-MOC) focused towards predicting the longevity of the stratospheric water vapour enhancement from the eruption, and its impacts on polar ozone. A CASE studentship with the UK Met Office has begun in October 2023, directly aligned to this continuing Leeds-Chengdu collaboration on the Hunga impacts on the stratospheric ozone layer
Collaborator Contribution Dr. Xin Zhou (lecturer in atmospheric science, Chengdu University) visited University of Leeds during 2020-2022, hosted by MeteorStrat co-Is Prof. Martyn Chipperfield and Dr. Wuhu Feng. Dr. Zhou's research analyses the influence of tropical ocean variability (El Nino Southern Oscillation, ENSO) on upwelling in the stratosphere, and the main area of collaboration aligned to the MeteorStrat science is re: volcanic impacts on climate and the stratospheric ozone layer. Dr. Zhou's analysis focused specifically on the UKESM1 simulated increase in stratospheric water vapour across the 27-member ensemble, showing that ENSO phase strongly modulates the post-eruption stratospheric increase in water vapour.
Impact Zhou, X., Mann, G. W., Feng, W., Dhomse, S. S., & Chipperfield, M. P. (2023). The influence of internal climate variability on stratospheric water vapor increases after large-magnitude explosive tropical volcanic eruptions. Geophysical Research Letters, 50, e2023GL103076. https://doi.org/10.1029/2023GL103076
Start Year 2021
 
Description Invited seminar at British Antarctic Survey (Wuhu Feng, MeteorStrat co-I) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Invited research seminar from Dr. Wuhu Feng (co-I, MeteorStrat) to British Antarctic Survey (Cambridge), on 8th May 2019
Year(s) Of Engagement Activity 2019
 
Description MeteorStrat PI co-leading new SPARC 2022-2025 limited-term cross-activity focus project "Hunga Tonga-Hunga Ha'apai stratospheric impacts", and a special report feeding into the 2026 WMO/UNEP Scientific Assessment of Ozone Depletion report 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Policymakers/politicians
Results and Impact SPARC has established a new activity to examine impacts of the Hunga Tonga-Hunga Ha'apai (HTHH) eruption of January 2022.

HTHH was the most explosive volcanic eruption in the satellite era, and the water-rich plume presents an opportunity to understand the impacts on the stratosphere of a large magnitude explosive phreatomagmatic eruption.

The wide range of satellite observations of the early stratospheric plume and its global dispersion will provide measurements to evaluate a range of models for their capabilities to represent stratospheric chemistry, aerosol and dynamics, in this case where both water vapor and aerosol are influencing radiative balances and stratospheric ozone.

There are numerous HTHH eruption observational and modeling studies that have been published, preprints of submitted papers, and new research in early stages.
As the dispersed volcanic cloud continues to evolve and its impacts emerge, additional papers will be published.

Because of the number and broad range of studies of the HTHH emissions and impacts, a SPARC limited-term cross-activity focused project is being organized to provide a forum for community discussions and synthesis, and to coordinate multi-model assessments.

During this 3-year HTHH SPARC activity, the team will co-ordinate research activities and aim to write a special Hunga-Tonga impacts report for publication in late-2025.

The report will directly feed into the upcoming 2026 UNEP/WMO Scientific Assessment of Ozone Depletion report, providing a benchmark synthesis of the impacts from the eruption.
Year(s) Of Engagement Activity 2022,2023
URL https://www.sparc-climate.org/activities/hunga-tonga/
 
Description Outreach workshop with British Geological Survey for UK volcano-climate science 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Other audiences
Results and Impact Workshop for UK volcano-climate science to the British Geological Survey, took place Jan 7th/8th 2020 at University of Cambridge
Year(s) Of Engagement Activity 2020
 
Description research seminar to 20 delegates from China Meteorological Administration (CMA, Beijing) on 18th November at Edinburgh Napier University Sighthill Campus, in Edinburgh 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Workshop at Edinburgh Napier University for interactions with visiting China Meteorological Administration (CMA), November 2019.
Year(s) Of Engagement Activity 2019