Analysis of the global atmospheric background sulfur budget in a multi-model framework

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(9), P. 5513 - 5548

Published: May 14, 2024

Abstract. A growing number of general circulation models are adapting interactive sulfur and aerosol schemes to improve the representation relevant physical chemical processes associated feedbacks. They motivated by investigations climate response major volcanic eruptions potential solar geoengineering scenarios. However, uncertainties in these not well constrained. Stratospheric sulfate is modulated emissions sulfur-containing species anthropogenic natural origin, including activity. While effects have been studied framework global model intercomparisons, background conditions cycle addressed such a way. Here, we fill this gap analyzing distribution main nine atmospheric for volcanically quiescent period. We use observational data evaluate results. Overall, agree that three dominant terms burdens (sulfate aerosol, OCS, SO2) make up about 98 % stratospheric 95 tropospheric sulfur. vary considerably partitioning between species. Models emission SO2 strongly affects burden northern hemispheric troposphere, while its importance very uncertain other regions, where much lower. Sulfate deposited all models, but values deviate factor 2. Additionally, wet dry deposition fluxes highly dependent. Inter-model variability low tropics increases towards poles. Differences largest dynamically active extratropical region could be attributed circulation. The differences budget among arise from both dynamical processes, whose interplay complicates bias attribution. Several problematic points identified individual related specifics chemistry schemes, resolution, cross-tropopause transport extratropics. Further intercomparison research needed with focus on clarification reasons biases, given topic injection studies.

Language: Английский

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Importance of microphysical settings for climate forcing by stratospheric SO₂ injections as modeled by SOCOL-AERv2

Geoscientific model development, Journal Year: 2024, Volume and Issue: 17(10), P. 4181 - 4197

Published: May 22, 2024

Abstract. Solar radiation modification by a sustained deliberate source of SO2 into the stratosphere (strat-SRM) has been proposed as an option for climate intervention. Global interactive aerosol–chemistry–climate models are often used to investigate potential cooling efficiencies and associated side effects hypothesized strat-SRM scenarios. A recent model intercomparison study composition–climate with stratospheric aerosol suggests that modeled response particular assumed injection strategy depends on type microphysical scheme (e.g., modal or sectional representation) alongside host resolution transport. Compared short-duration volcanic emissions, continuous injections in scenarios may pose greater challenge numerical implementation processes such nucleation, condensation, coagulation. This explores how changing time steps sequencing SOCOL-AERv2 (40 mass bins) affects model-predicted ozone layer impacts considering 5 25 Tg(S) yr−1 at 20 km altitude between 30° S N. The experiments consider year 2040 be boundary conditions ozone-depleting substances greenhouse gases (GHGs). We focus length step call sequence nucleation two competing sink gaseous H2SO4. Under background conditions, we find no effect setup simulated properties. However, high sulfur loadings reached injecting default 6 min, from “condensation first” “nucleation leads massive increase number densities particles mode (R<0.01 µm) small decrease coarse-mode (R>1 µm). As expected, influence becomes negligible when is reduced few seconds, solutions converging size distribution pronounced mode. While main features spatial patterns forcing not strongly affected configuration, absolute numbers vary considerably. For extreme yr−1, net global radiative ranges −2.3 −5.3 W m−2, depending configuration. Nucleation first shifts towards radii better suited solar scattering (0.3 µm <R< 0.4 µm), enhancing intervention efficiency. shift, however, generates more ultrafine particles, increasing surface area density resulting 10 DU (Dobson units) less (about 3 % total column) northern mid-latitudes (6 %) over polar caps compared condensation approach. Our results suggest reasonably short 2 min must applied accurately capture magnitude H2SO4 supersaturation eruptions. Taken together, these underscore structural aspects representation become important under elevated determining atmospheric chemistry impacts.

Language: Английский

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Initial atmospheric conditions control transport of volcanic volatiles, forcing and impacts

Atmospheric chemistry and physics, Journal Year: 2024, Volume and Issue: 24(10), P. 6233 - 6249

Published: May 28, 2024

Abstract. Volcanic eruptions impact the climate and environment. The volcanic forcing is determined by eruption source parameters, including mass composition of volatiles, season, latitude, injection altitude. Moreover, initial atmospheric conditions system play an important role in shaping response. However, our understanding combination these factors, distinctions between tropical extratropical eruptions, co-injection sulfur halogens remains limited. Here, we perform ensemble simulations at 15 64° N January, injecting 17 Mt SO2 together with HCl HBr 24 km Our findings reveal that control transport volatiles from first month modulate subsequent latitudinal distribution sulfate aerosols halogens. This results different forcing, surface temperature ozone responses over globe Northern Hemisphere extratropics (NHET) among model members conditions. NH exhibit a larger NHET mean cooling depletion compared eruptions. lead to more prolonged impacts both globally NHET. sensitivity varying parameters dependency discussed, emphasizing need for future multi-model studies consider influence on impacts.

Language: Английский

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Emulating inconsistencies in stratospheric aerosol injection

Environmental Research Climate, Journal Year: 2024, Volume and Issue: 3(3), P. 035012 - 035012

Published: May 29, 2024

Abstract Stratospheric aerosol injection (SAI) would involve the addition of sulfate aerosols in stratosphere to reflect part incoming solar radiation, thereby cooling climate. Studies trying explore impacts SAI have often focused on idealized scenarios without explicitly introducing what we call ‘inconsistencies’ a deployment. A concern discussed is happen climate system after an abrupt termination its deployment, whether inadvertent or deliberate. However, there much wider range plausible inconsistencies deployment than that should be evaluated better understand associated risks. In this work, simulate few representative pre-existing scenario: termination, decade-long gradual phase-out, and 1 year 2 temporary interruptions After examining their impacts, use these simulations train emulator, project global mean temperature response for broader set Our work highlights capacity finite simulated include inform emulator capable expanding space one might want far more quickly efficiently.

Language: Английский

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Volcanic Drivers of Stratospheric Sulfur in GFDL ESM4

Journal of Advances in Modeling Earth Systems, Journal Year: 2023, Volume and Issue: 15(5)

Published: May 1, 2023

Abstract Stratospheric injections of sulfur dioxide from major volcanic eruptions perturb the Earth's global radiative balance and dominate variability in stratospheric loading. The atmospheric component GFDL Earth System Model (ESM4.1) uses a bulk aerosol scheme previously prescribed distribution optical properties stratosphere. To quantify contributions to cycle resulting climate impact, we modified ESM4.1 simulate sulfate aerosols prognostically. Driven by explicit emissions precursors non‐volcanic sources, conduct simulations 1989 2014, with focus on Mt. Pinatubo eruption. We evaluate our interactive representation against data Moderate Resolution Imaging Spectroradiometer, Multi‐angle SpectroRadiometer, Advanced Very High Radiometer, Infrared Radiation Sounder, Aerosol Gas Experiment II. assess key processes associated aerosols, performed sensitivity analysis burden eruption varying injection heights, emission amount, sulfate's dry effective radius. find that simulated mass depth model are sensitive these parameters, especially SO 2 height, optimal combination parameters depends metric evaluate.

Language: Английский

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Assessing Outcomes in Stratospheric Aerosol Injection Scenarios Shortly After Deployment

Earth s Future, Journal Year: 2023, Volume and Issue: 11(5)

Published: May 1, 2023

Stratospheric aerosol injection (SAI) is a proposed form of climate intervention that would release reflective particles into the stratosphere, thereby reducing solar insolation and cooling planet. The response to SAI not well understood, particularly on short-term time horizons frequently used by decision-makers planning practitioners assess information. We demonstrate two framings explore in decade after deployment modeling experiments with parallel no-SAI simulations. first framing, which we call snapshot around deployment, displays change over within scenarios applies question "What happens before deployed model?" second impact, difference between simulations, corresponding impact given relative no intervention?" apply these annual mean 2 m temperature, precipitation, precipitation extreme during 10 yr large ensembles Earth system model simulations comprehensively represent both process response, connect results implications for other variables. show robustly reduces changes many high-impact variables even short timescales where forced relatively small, but details depend version, greenhouse gas emissions scenario, aspects experimental design.

Language: Английский

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OMPS-LP aerosol extinction coefficients and their applicability in GloSSAC

Atmospheric chemistry and physics, Journal Year: 2025, Volume and Issue: 25(1), P. 535 - 553

Published: Jan. 16, 2025

Abstract. The Global Space-based Stratospheric Aerosol Climatology (GloSSAC) is essential for understanding and modeling the climatic impacts of stratospheric aerosols. It relies primarily on data from Gas Experiment (SAGE) satellite series, supplemented by Optical Spectrograph Infrared Imaging System (OSIRIS) Cloud-Aerosol Lidar Pathfinder Satellite Observations (CALIPSO). GloSSAC currently provides aerosol extinction coefficients optical depths at 525 1020 nm. With CALIPSO decommissioned OSIRIS nearing end its operational life, SAGE III/ISS (International Space Station) will soon become sole source GloSSAC, but it only be available as long ISS operational, until around 2030. Therefore, incorporating other measurements, such those Ozone Mapping Profiler Suite Limb (OMPS-LP), critical. OMPS-LP has provided continuous coefficient measurements since 2012 with a retrieval algorithm developed NASA, i.e., OMPS(NASA). However, OMPS(NASA) been shown to overestimate coefficients, particularly after 2022 Hunga Tonga eruption, compared tomographic OMPS University Saskatchewan (OMPS(SASK)) III/ISS. Our analysis shows that indeed exhibits consistently high bias (>50 %) following large volcanic eruptions pyrocumulonimbus plumes intense wildfires, while OMPS(SASK) reasonable agreement between 40° S N. This overestimation leads an effective radiative forcing (ERF) associated model-simulated global surface temperature response factor about 2.

Language: Английский

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World Climate Research Programme lighthouse activity: an assessment of major research gaps in solar radiation modification research

Frontiers in Climate, Journal Year: 2025, Volume and Issue: 7

Published: Feb. 5, 2025

It is increasingly evident that maintaining global warming at levels below those agreed in the legally binding international treaty on climate change. i.e., Paris Agreement, going to be extremely challenging using conventional mitigation techniques. While future scenarios of change frequently include extensive use terrestrial and marine carbon dioxide removal second part 21st century, it unproven these techniques can scaled-up reach scale required significantly reduce concentrations atmospheric significant uncertainties detrimental side-effects exist. These issues have led increasing interest so-called “Solar Radiation Modification” whereby mean temperature Earth reduced by either blocking a small fraction sunlight from reaching or Earth’s albedo reflect proportion incident back out space. Here we systematically identify key research gaps associated with two most prominent Solar Modification techniques, Stratospheric Aerosol Injection (SAI) Marine Cloud Brightening (MCB). We provide an assessment other less SRM assert transparency inclusivity essential providing objective impartial findings each every stakeholder equitable way.

Language: Английский

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Modulation of the northern polar vortex by the Hunga Tonga–Hunga Ha'apai eruption and the associated surface response

Atmospheric chemistry and physics, Journal Year: 2025, Volume and Issue: 25(6), P. 3623 - 3634

Published: March 27, 2025

Abstract. The January 2022 Hunga Tonga–Hunga Ha’apai (HT) eruption injected sulfur dioxide and unprecedented amounts of water vapour (WV) into the stratosphere. Given manifold impacts previous volcanic eruptions, full implications these emissions are a topic active research. This study explores dynamical perturbed upper-atmospheric composition using an ensemble simulation with Earth system model SOCOLv4. simulations replicate observed anomalies in stratospheric lower-mesospheric chemical reveal novel pathway linking water-rich eruptions to surface climate anomalies. We show that early 2023 excess WV caused significant negative tropical upper-stratospheric mesospheric ozone temperature, forcing atmospheric circulation response particularly affected Northern Hemisphere polar vortex (PV). decreased temperature gradient leads weakening PV, which propagates downward similarly sudden warmings (SSWs) drives via stratosphere–troposphere coupling. These results underscore potential HT create favorable conditions for SSWs subsequent winters as long near-stratopause cooling effect persists. Our findings highlight complex interactions between activity dynamics offer crucial insights future modelling attribution.

Language: Английский

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Stratospheric residence time and the lifetime of volcanic stratospheric aerosols

Atmospheric chemistry and physics, Journal Year: 2025, Volume and Issue: 25(6), P. 3821 - 3839

Published: April 2, 2025

Abstract. The amount of time that volcanic aerosols spend in the stratosphere is one primary factors influencing climate impact eruptions. Stratospheric aerosol persistence has been described different ways, with many works quoting an approximately 12-month “residence time” for from large tropical Here, we aim to develop a framework describing evolution global stratospheric after major eruptions and quantifying its persistence, based on satellite-based observations, tracer transport simulations, simple conceptual modelling. We show residence air, which estimated through passive pulse experiments factor lifetime aerosols, strongly dependent injection latitude height, especially strong sensitivity height first 4 km above tropopause. Simulated best by model includes lag between initiation removal stratosphere. Based analysis 1991 Pinatubo eruption 22 months. estimate potential observational uncertainties this lifetime, finding it unlikely less than 18

Language: Английский

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