Recovered measurements of the 1960s stratospheric aerosol layer and UM-UKCA model experiments to assess the Mar 1963 Agung, Sep 1965 Taal and Aug 1966 Awu volcanic aerosol clouds

The WCRP-SPARC initiative on stratospheric sulphur (SSiRC) has begun a new activity to recover past observational datasets of the stratospheric aerosol layer.The data rescue activity aims to provide additional constraints for volcanic impacts on climate and is organised into three time-periods:<ol><li>The quiescent period prior to the major eruption 1963 Agung eruption,</li> <li>The period of strong volcanic activity during 1963-1969,</li> <li>The Jul-Dec 1991 period after Pinatubo when the SAGE-II signal was saturated.</li> </ol>A new page within the SSiRC website gives further information on the datasets within this activity ( http://www.sparc-ssirc.org &#160;--> Activities --> Data Rescue).In this presentation, we explain the 1963-1969 component of the data rescue, and compare the CMIP5 and CMIP6 volcanic aerosol datasets during this period, post-Agung interactive stratospheric aerosol model simulations and a preliminary analysis of 15-year global-mean surface temperature trends from CMIP6 historical integrations for 1950-1980.The 1960s was a strongly volcanically active decade, with the major 1963 Agung eruption and tropical stratosphere-injecting eruptions in 1965 (Taal), 1966 (Awu) and 1968 (Fernandina) generating a prolonged period of strong natural surface cooling.Less than a year after the Agung eruption, the first in-situ measurements of a major volcanic aerosol cloud were made with dust-sondes from Minneapolis measuring aerosol particle concentrations with 10 soundings between 1963 and 1965 (6 in 1963-4).Global surveys with the U-2 aircraft were equipped with impactors to measure stratospheric aerosol particle size distribution and composition, for example detecting the presence of volcanic ash within the Agung volcanic plume.Early ground-based active remote sensing measurements (lidar, searchlight) also measured the vertical profile of the Agung-enhanced stratospheric aerosol layer.The main purpose of the SSiRC data rescue is to provide constraints for interactive stratospheric aerosol models, aligning with the ISA-MIP activity, which could potentially lead to new volcanic forcing datasets for climate models, ultimately thereby aiming to improve attribution of anthropogenic change and future projections.

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The Interactive Stratospheric Aerosol Model Intercomparison Project (ISA-MIP): motivation and experimental design

Geoscientific Model Development ◽

10.5194/gmd-11-2581-2018 ◽

2018 ◽

Vol 11 (7) ◽

pp. 2581-2608 ◽

Cited By ~ 17

Author(s):

Claudia Timmreck ◽

Graham W. Mann ◽

Valentina Aquila ◽

Rene Hommel ◽

Lindsay A. Lee ◽

...

Keyword(s):

Radiative Forcing ◽

Volcanic Eruptions ◽

Stratospheric Aerosol ◽

Transport Processes ◽

Aerosol Layer ◽

Model Intercomparison ◽

Aerosol Model ◽

Model Experiments ◽

Aerosol Forcing ◽

Intercomparison Project

Abstract. The Stratospheric Sulfur and its Role in Climate (SSiRC) Interactive Stratospheric Aerosol Model Intercomparison Project (ISA-MIP) explores uncertainties in the processes that connect volcanic emission of sulfur gas species and the radiative forcing associated with the resulting enhancement of the stratospheric aerosol layer. The central aim of ISA-MIP is to constrain and improve interactive stratospheric aerosol models and reduce uncertainties in the stratospheric aerosol forcing by comparing results of standardized model experiments with a range of observations. In this paper we present four co-ordinated inter-model experiments designed to investigate key processes which influence the formation and temporal development of stratospheric aerosol in different time periods of the observational record. The Background (BG) experiment will focus on microphysics and transport processes under volcanically quiescent conditions, when the stratospheric aerosol is controlled by the transport of aerosols and their precursors from the troposphere to the stratosphere. The Transient Aerosol Record (TAR) experiment will explore the role of small- to moderate-magnitude volcanic eruptions, anthropogenic sulfur emissions, and transport processes over the period 1998–2012 and their role in the warming hiatus. Two further experiments will investigate the stratospheric sulfate aerosol evolution after major volcanic eruptions. The Historical Eruptions SO2 Emission Assessment (HErSEA) experiment will focus on the uncertainty in the initial emission of recent large-magnitude volcanic eruptions, while the Pinatubo Emulation in Multiple models (PoEMS) experiment will provide a comprehensive uncertainty analysis of the radiative forcing from the 1991 Mt Pinatubo eruption.

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Long-range isentropic transport of stratospheric aerosols over Southern Hemisphere following the Calbuco eruption in April 2015

10.5194/acp-2017-544 ◽

2017 ◽

Cited By ~ 1

Author(s):

Nelson Bègue ◽

Damien Vignelles ◽

Gwenaël Berthet ◽

Thierry Portafaix ◽

Guillaume Payen ◽

...

Keyword(s):

Southern Hemisphere ◽

Transient Behavior ◽

Stratospheric Aerosol ◽

Aerosol Layer ◽

Reunion Island ◽

Volcanic Aerosol ◽

Réunion Island ◽

One Year ◽

The Impact ◽

Aerosol Plume

Abstract. After 43 years of inactivity, the Calbuco volcano which is located in the southern part of Chile erupted on 22 April 2015. The space-time evolutions (distribution and transport) of its aerosol plume are investigated by combining satellite (CALIOP, IASI, OMPS), in situ aerosol counting (LOAC OPC) and lidar observations, and the MIMOSA advection model. The Calbuco aerosol plume reached the Indian Ocean 1 week after the eruption. Over the Reunion Island site (21° S; 55.5° E), the aerosol signal was unambiguously enhanced in comparison with "background" conditions with a volcanic aerosol layer extending from 18 km to 21 km during the May–July period. All the data reveal an increase by a factor of ~ 2 in the SAOD (Stratospheric Aerosol Optical Depth) with respect to values observed before the eruption. The aerosol e-folding time is approximately 90 days. Microphysical measurements obtained before, during and after the eruption reflecting the impact of the Calbuco eruption on the lower stratospheric aerosol content have been analyzed over Reunion site. During the passage of the plume, the volcanic aerosol was characterized by an effective radius of 0.16 ± 0.02 µm with an unimodal lognormal size distribution and the aerosol number concentration appears 20 times higher than before and one year after the eruption. A tendency toward "background" conditions has been observed about one year after the eruption, by April 2016. The volcanic aerosol plume is advected eastward in the Southern Hemisphere and its latitudinal extent is clearly bounded by the subtropical barrier and the polar vortex. The transient behavior of the aerosol layers observed above Reunion Island between May and July 2015 reflects an inhomogeneous geographical distribution of the plume which is controlled by the latitudinal motion of these dynamical barriers.

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Interactive Stratospheric Aerosol models response to different sulfur injection amount and altitude distribution during volcanic eruption

10.5194/egusphere-egu21-13387 ◽

2021 ◽

Author(s):

Ilaria Quaglia ◽

Christoph Brühl ◽

Sandip Dhomse ◽

Henning Franke ◽

Anton Laakso ◽

...

Keyword(s):

Volcanic Eruptions ◽

Stratospheric Aerosol ◽

Climate Modelling ◽

Aerosol Layer ◽

Volcanic Aerosol ◽

Surface Cooling ◽

Altitude Distribution ◽

Aerosol Cloud ◽

Modelling Studies ◽

Intercomparison Project

Large magnitude tropical volcanic eruptions emit sulphur dioxide and other gases directly into the stratosphere, creating a long-lived volcanic aerosol cloud which scatter incoming solar radiation, absorbs outgoing terrestrial radiation, and can strongly affect the composition of the stratosphere.Such major volcanic enhancements of the stratospheric aerosol layer have strong &#8220;direct effects&#8221; on climate via these influences on radiative transfer, primarily surface cooling via the reduced insolation, but also have a range of indirect effects, due to the volcanic aerosol cloud&#8217;s effects on stratospheric circulation, dynamics and chemistry.In this study, we investigate the 3 largest volcanic enhancements to the stratospheric aerosol layer in the last 100 years (Mt Agung 1963; Mt El Chich&#243;n 1982; Mt Pinatubo 1991), comparing co-ordinated simulations within the so-called HErSEA experiments (Historical Eruptions SO2 Emission Assessment) several national climate modelling centres carried out for the model intercomparison project ISA-MIP.The HErSEA experiment saw participating models performing interactive stratospheric aerosol simulations of each of the volcanic aerosol clouds with common upper-, mid- and lower-estimate amounts and injection heights of sulfur dioxide, in order to better understand known differences among modelling studies for which initial emission gives best agreement with observations.&#160;First, we compare results of several models HErSEA simulations with a range of observations, with the aim to find where there is agreement between the models and where there are differences, at the different initial sulfur injection amount and altitude distribution.In this way, we could understand the differences and limitations in the mechanisms that controls the dynamical, microphysical and chemical processes of stratospheric aerosol layer.

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The Interactive Stratospheric Aerosol Model Intercomparison Project (ISA-MIP): Motivation and experimental design

10.5194/gmd-2017-308 ◽

2018 ◽

Cited By ~ 3

Author(s):

Claudia Timmreck ◽

Graham W. Mann ◽

Valentina Aquila ◽

Rene Hommel ◽

Lindsay A. Lee ◽

...

Keyword(s):

Radiative Forcing ◽

Volcanic Eruptions ◽

Stratospheric Aerosol ◽

Transport Processes ◽

Aerosol Layer ◽

Model Intercomparison ◽

Aerosol Model ◽

Model Experiments ◽

Aerosol Forcing ◽

Intercomparison Project

Abstract. The Stratospheric Sulfur and its Role in Climate (SSiRC) interactive stratospheric aerosol model intercomparison project (ISA-MIP) explores uncertainties in the processes that connect volcanic emission of sulphur gas species and the radiative forcing associated with the resulting enhancement of the stratospheric aerosol layer. The central aim of ISA-MIP is to constrain and improve interactive stratospheric aerosol models and reduce uncertainties in the stratospheric aerosol forcing by comparing results of standardized model experiments with a range of observations. In this paper we present 4 co-ordinated inter-model experiments designed to investigate key processes which influence the formation and temporal development of stratospheric aerosol in different time periods of the observational record. The Background (BG) experiment will focus on microphysics and transport processes under volcanically quiescent conditions, when the stratospheric aerosol is controlled by the transport of aerosols and their precursors from the troposphere to the stratosphere. The Transient Aerosol Record (TAR) experiment will explore the role of small- to moderate-magnitude volcanic eruptions, anthropogenic sulphur emissions and transport processes over the period 1998–2012 and their role in the warming hiatus. Two further experiments will investigate the stratospheric sulphate aerosol evolution after major volcanic eruptions. The Historical Eruptions SO2 Emission Assessment (HErSEA) experiment will focus on the uncertainty in the initial emission of recent large-magnitude volcanic eruptions, while the Pinatubo Emulation in Multiple models (PoEMS) experiment will provide a comprehensive uncertainty analysis of the radiative forcing from the 1991 Mt. Pinatubo eruption.

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Detection of an enhanced stratospheric aerosol layer above Europe one year after the eruption of the volcano Raikoke

10.5194/egusphere-egu21-14197 ◽

2021 ◽

Author(s):

Laura Tomsche ◽

Andreas Marsing ◽

Tina Jurkat-Witschas ◽

Johannes Lucke ◽

Katharina Kaiser ◽

...

Keyword(s):

Mass Spectrometer ◽

Lower Stratosphere ◽

Volcanic Eruptions ◽

Stratospheric Aerosol ◽

Sulfate Aerosol ◽

Aerosol Layer ◽

Volcanic Aerosol ◽

Aerosol Mass Spectrometer ◽

Aerosol Mass

Extreme volcanic eruptions inject significant amounts of sulfur-containing species into the lower stratosphere and sustain the stratospheric aerosol layer which tends to cool the atmosphere and surface temperatures.During the BLUESKY campaign in May/June 2020, the aerosol composition and its precursor gas SO2 were measured with a time-of-flight aerosol mass spectrometer onboard the research aircraft HALO and with a atmospheric chemical ionization mass spectrometer onboard the DLR Falcon. While SO2 was slightly above background levels in the lower stratosphere above Europe, the aerosol mass spectrometer detected an extended aerosol layer. This sulfate aerosol layer was observed on most of the HALO flights and the sulfate mixing ratio increased significantly between 10 and 14 km altitude. Back trajectory calculations show no recent transport of polluted boundary layer air or ground-based emissions into the lower stratosphere. Therefore, we suggest that the stratospheric sulfate aerosol layer might be attributed to the aged stratospheric plume of the volcano Raikoke in Japan. In June 2019, Raikoke injected huge amounts of SO2 into the lower stratosphere, which were converted to sulfate and contributed to the stratospheric aerosol layer. This decaying volcanic aerosol layer was observed with the aerosol mass spectrometer over Europe a year after the eruption. The long-term volcanic remnants enhance the total stratospheric aerosol surface area, facilitate heterogeneous reactions on these particles and provide additional cloud condensation nuclei in the UTLS. They further offset some of the reduced sulfur burden from aviation that was observed during the COVID-19 lockdown in 2020. The sensitive and highly time resolved airborne measurements of composition and size of stratospheric aerosol from an explosive volcanic eruption help to better constrain sulfur chemistry in the lower stratosphere, validate satellite observations near their detection threshold and can be used to evaluate dispersion and chemistry-climate models on long-term effects of volcanic aerosol.&#160;

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Long-range transport of stratospheric aerosols in the Southern Hemisphere following the 2015 Calbuco eruption

Atmospheric Chemistry and Physics ◽

10.5194/acp-17-15019-2017 ◽

2017 ◽

Vol 17 (24) ◽

pp. 15019-15036 ◽

Cited By ~ 16

Author(s):

Nelson Bègue ◽

Damien Vignelles ◽

Gwenaël Berthet ◽

Thierry Portafaix ◽

Guillaume Payen ◽

...

Keyword(s):

Southern Hemisphere ◽

Transient Behavior ◽

Stratospheric Aerosol ◽

Aerosol Layer ◽

Reunion Island ◽

Volcanic Aerosol ◽

Réunion Island ◽

The Impact ◽

Aerosol Plume ◽

Lidar Observations

Abstract. After 43 years of inactivity, the Calbuco volcano, which is located in the southern part of Chile, erupted on 22 April 2015. The space–time evolutions (distribution and transport) of its aerosol plume are investigated by combining satellite (CALIOP, IASI, OMPS), in situ aerosol counting (LOAC OPC) and lidar observations, and the MIMOSA advection model. The Calbuco aerosol plume reached the Indian Ocean 1 week after the eruption. Over the Reunion Island site (21° S, 55.5° E), the aerosol signal was unambiguously enhanced in comparison with background conditions, with a volcanic aerosol layer extending from 18 to 21 km during the May–July period. All the data reveal an increase by a factor of ∼  2 in the SAOD (stratospheric aerosol optical depth) with respect to values observed before the eruption. The aerosol mass e-folding time is approximately 90 days, which is rather close to the value ( ∼  80 days) reported for the Sarychev eruption. Microphysical measurements obtained before, during, and after the eruption reflecting the impact of the Calbuco eruption on the lower stratospheric aerosol content have been analyzed over the Reunion Island site. During the passage of the plume, the volcanic aerosol was characterized by an effective radius of 0.16 ± 0.02 µm with a unimodal size distribution for particles above 0.2 µm in diameter. Particle concentrations for sizes larger than 1 µm are too low to be properly detected by the LOAC OPC. The aerosol number concentration was ∼  20 times higher that observed before and 1 year after the eruption. According to OMPS and lidar observations, a tendency toward conditions before the eruption was observed by April 2016. The volcanic aerosol plume is advected eastward in the Southern Hemisphere and its latitudinal extent is clearly bounded by the subtropical barrier and the polar vortex. The transient behavior of the aerosol layers observed above Reunion Island between May and July 2015 reflects an inhomogeneous spatio-temporal distribution of the plume, which is controlled by the localization of these dynamical barriers.

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Isotopic studies of the sulfur component of the stratospheric aerosol layer

Tellus ◽

10.3402/tellusa.v26i1-2.9781 ◽

1974 ◽

Vol 26 (1-2) ◽

pp. 222-234 ◽

Cited By ~ 50

Author(s):

A. W. Castleman Jr. ◽

H. R. Munkelwitz ◽

B. Manowitz

Keyword(s):

Stratospheric Aerosol ◽

Aerosol Layer ◽

Isotopic Studies

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Differences in the Evolution of Pyrocumulonimbus and Volcanic Stratospheric Plumes as Observed by CATS and CALIOP Space-Based Lidars

Atmosphere ◽

10.3390/atmos11101035 ◽

2020 ◽

Vol 11 (10) ◽

pp. 1035

Author(s):

Kenneth Christian ◽

John Yorks ◽

Sampa Das

Keyword(s):

Pacific Northwest ◽

Stratospheric Aerosol ◽

Volcanic Aerosol ◽

Volcanic Plumes ◽

Size And Shape ◽

Altitude Dependence ◽

Volcanic Events ◽

Spatial Propagation ◽

Depolarization Ratios

Recent fire seasons have featured volcanic-sized injections of smoke aerosols into the stratosphere where they persist for many months. Unfortunately, the aging and transport of these aerosols are not well understood. Using space-based lidar, the vertical and spatial propagation of these aerosols can be tracked and inferences can be made as to their size and shape. In this study, space-based CATS and CALIOP lidar were used to track the evolution of the stratospheric aerosol plumes resulting from the 2019–2020 Australian bushfire and 2017 Pacific Northwest pyrocumulonimbus events and were compared to two volcanic events: Calbuco (2015) and Puyehue (2011). The pyrocumulonimbus and volcanic aerosol plumes evolved distinctly, with pyrocumulonimbus plumes rising upwards of 10 km after injection to altitudes of 30 km or more, compared to small to modest altitude increases in the volcanic plumes. We also show that layer-integrated depolarization ratios in these large pyrocumulonimbus plumes have a strong altitude dependence with more irregularly shaped particles in the higher altitude plumes, unlike the volcanic events studied.

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Pinatubo volcanic aerosol layer decay observed at Ahmedabad (23°N), India, using neodymium:yttrium/aluminium/garnet backscatter lidar

Journal of Geophysical Research Atmospheres ◽

10.1029/95jd02195 ◽

1995 ◽

Vol 100 (D11) ◽

pp. 23209 ◽

Cited By ~ 19

Author(s):

A. Jayaraman ◽

S. Ramachandran ◽

Y. B. Acharya ◽

B. H. Subbaraya

Keyword(s):

Aerosol Layer ◽

Volcanic Aerosol

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