Supplementary material to "Balloon borne aerosol-cloud interaction studies (BACIS): New observational techniques to understand and quantify aerosol effects on clouds"

Abstract. Aerosol emissions from volcanic eruptions in otherwise clean environments are regarded as natural experiments where the aerosol effects on clouds and climate can be partitioned from other effects like meteorology and anthropogenic emissions. In this work, we combined satellite retrievals, reanalysis products, and atmospheric modeling to analyze the mechanism of aerosol-cloud interactions during two degassing events at the Kilauea Volcano in 2008 and 2018. The eruptive nature of the 2008 and 2018 degassing events was distinct from long-term volcanic activity for Kilauea. For both events, we performed a comprehensive investigation on the effects of aerosol emissions on macro and microphysical cloud processes for both liquid and ice clouds. This is the first time such an analysis has been reported for the 2018 event. Similarities between both events suggested that aerosol-cloud interactions related to the cloud albedo modification were likely decoupled from local meteorology. In both events the ingestion of aerosols within convective parcels enhanced the detrainment of condensate in the upper troposphere resulting in deeper clouds than in pristine conditions. Accounting for ice nucleation on ash particles led to enhanced ice crystal concentrations at cirrus levels and a slight decrease in ice water content, improving the correlation of the model results with the satellite retrievals. Overall, aerosol loading, plume characteristics, and meteorology contributed to observed and simulated changes in clouds during the Kilauea degassing events.

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Diurnal variation of heavy rainfall over the Beijing-Tianjin-Hebei region: Role of aerosol cloud effect and its sensitivity to moisture

10.5194/acp-2018-1072 ◽

2018 ◽

Cited By ~ 1

Author(s):

Siyuan Zhou ◽

Jing Yang ◽

Chuanfeng Zhao ◽

Wei-Chyung Wang ◽

Daoyi Gong ◽

...

Keyword(s):

Diurnal Variation ◽

Heavy Rainfall ◽

Lower Troposphere ◽

Cloud Droplet ◽

Effective Radius ◽

Aerosol Cloud ◽

Cloud Effect ◽

Aerosol Effects ◽

Different Characteristics

Abstract. Our recent study found that, during 2002–2012, the diurnal variation of heavy rainfall over Beijing-Tianjin-Hebei (BTH) region exhibits different characteristics between clean and polluted environment. Here we use satellite cloud products together with meteorology and aerosol data to further examine the aerosol impact on the associated clouds focusing on its sensitivity to moisture. During the days with large aerosol loading, the characteristics of earlier starting time, earlier peak hour and the longer duration of heavy rainfall are usually accompanied by increased cloud fraction, reduced cloud top height and increased/reduced liquid/ice effective radius. However, the aerosol effects on the cloud top and liquid effective radius are distinct at lower and higher humidity. Different from the radiative effect that black carbon heats the lower troposphere and may generate the earlier start of heavy rainfall, the aerosol cloud effect enhances the efficiency of precipitation and advances the rainfall peak, which may be ascribed to increased cloud droplet number and cloud water, enhanced collision-coalescence and accelerated rainfall formation when the background moisture supply is sufficient. The speculation warrants further numerical experiment to verify.

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Supplementary material to "Impact of biomass burning aerosols on radiation, clouds, and precipitation over the Amazon during the dry season: dependence of aerosol-cloud and aerosol-radiation interactions on aerosol loading"

10.5194/acp-2020-191-supplement ◽

2020 ◽

Author(s):

Lixia Liu ◽

Yafang Cheng ◽

Siwen Wang ◽

Chao Wei ◽

Mira Pöhlker ◽

...

Keyword(s):

Biomass Burning ◽

Dry Season ◽

Aerosol Cloud ◽

Aerosol Loading ◽

Supplementary Material

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Supplementary material to "Aerosol-cloud interactions in mixed-phase convective clouds. Part 1: Aerosol perturbations"

10.5194/acp-2017-788-supplement ◽

2017 ◽

Author(s):

Annette K. Miltenberger ◽

Paul R. Field ◽

Adrian A. Hill ◽

Phil Rosenberg ◽

Ben J. Shipway ◽

...

Keyword(s):

Mixed Phase ◽

Convective Clouds ◽

Aerosol Cloud ◽

Supplementary Material ◽

Aerosol Cloud Interactions

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Supplementary material to "A new approach to simulate aerosol effects on cirrus clouds in EMAC v2.54"

10.5194/gmd-2019-212-supplement ◽

2019 ◽

Author(s):

Mattia Righi ◽

Johannes Hendricks ◽

Ulrike Lohmann ◽

Christof Gerhard Beer ◽

Valerian Hahn ◽

...

Keyword(s):

Cirrus Clouds ◽

New Approach ◽

Supplementary Material ◽

Aerosol Effects

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Addressing the difficulties in quantifying the Twomey effect for marine warm clouds from multi-sensor satellite observations and reanalysis

10.5194/acp-2021-999 ◽

2022 ◽

Author(s):

Hailing Jia ◽

Johannes Quaas ◽

Edward Gryspeerdt ◽

Christoph Böhm ◽

Odran Sourdeval

Keyword(s):

Radiative Forcing ◽

Cloud Droplet ◽

Influential Factors ◽

Satellite Observations ◽

Cloud Base ◽

Aerosol Cloud ◽

Spatio Temporal ◽

Observational Estimate ◽

Aerosol Cloud Interactions ◽

Aerosol Effects

Abstract. Aerosol–cloud interaction is the most uncertain component of the overall anthropogenic forcing of the climate, in which the Twomey effect plays a fundamental role. Satellite-based estimates of the Twomey effect are especially challenging, mainly due to the difficulty in disentangling aerosol effects on cloud droplet number concentration (Nd) from possible confounders. By combining multiple satellite observations and reanalysis, this study investigates the impacts of a) updraft, b) precipitation, c) retrieval errors, as well as (d) vertical co-location between aerosol and cloud, on the assessment of Nd-toaerosol sensitivity (S) in the context of marine warm (liquid) clouds. Our analysis suggests that S increases remarkably with both cloud base height and cloud geometric thickness (proxies for vertical velocity at cloud base), consistent with stronger aerosol-cloud interactions at larger updraft velocity. In turn, introducing the confounding effect of aerosol–precipitation interaction can artificially amplify S by an estimated 21 %, highlighting the necessity of removing precipitating clouds from analyses on the Twomey effect. It is noted that the retrieval biases in aerosol and cloud appear to underestimate S, in which cloud fraction acts as a key modulator, making it practically difficult to balance the accuracies of aerosol–cloud retrievals at aggregate scales (e.g., 1° × 1° grid). Moreover, we show that using column-integrated sulfate mass concentration (SO4C) to approximate sulfate concentration at cloud base (SO4B) can result in a degradation of correlation with Nd, along with a nearly twofold enhancement of S, mostly attributed to the inability of SO4C to capture the full spatio-temporal variability of SO4B. These findings point to several potential ways forward to account for the major influential factors practically by means of satellite observations and reanalysis, aiming at an optimal observational estimate of global radiative forcing due to the Twomey effect.

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Aerosol Effects on Instability, Circulations, Clouds, and Precipitation

Advances in Meteorology ◽

10.1155/2014/683950 ◽

2014 ◽

Vol 2014 ◽

pp. 1-8 ◽

Cited By ~ 9

Author(s):

Seoung-Soo Lee ◽

Wei-Kuo Tao ◽

Chang-Hoon Jung

Keyword(s):

Climate Change ◽

Review Paper ◽

Future Climate ◽

Convective Clouds ◽

Aerosol Cloud ◽

Cloud Dynamics ◽

Deep Convective Clouds ◽

Environmental Instability ◽

Aerosol Cloud Interactions ◽

Aerosol Effects

It is well known that increasing aerosol and associated changes in aerosol-cloud interactions and precipitation since industrialization have been playing an important role in climate change, but this role has not been well understood. This prevents us from predicting future climate with a good confidence. This review paper presents recent studies on the changes in the aerosol-cloud interactions and precipitation particularly in deep convective clouds. In addition, this review paper discusses how to improve our understanding of these changes by considering feedbacks among aerosol, cloud dynamics, cloud and its embedded circulations, and microphysics. Environmental instability basically determines the dynamic intensity of clouds and thus acts as one of the most important controls on these feedbacks. As a first step to the improvement of the understanding, this paper specifically elaborates on how to link the instability to the feedbacks.

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