Articles | Volume 7, issue 4
https://doi.org/10.5194/gmd-7-1535-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/gmd-7-1535-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Development and technical paper
| 
24 Jul 2014
Development and technical paper |
| 24 Jul 2014
An investigation into the performance of four cloud droplet activation parameterisations
E. Simpson
Centre for Atmospheric Science, School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
P. Connolly
Centre for Atmospheric Science, School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
G. McFiggans
Centre for Atmospheric Science, School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK
Related authors
Emma L. Simpson, Paul J. Connolly, and Gordon McFiggans
Atmos. Chem. Phys., 18, 7237–7250, https://doi.org/10.5194/acp-18-7237-2018, https://doi.org/10.5194/acp-18-7237-2018, 2018
Short summary
Short summary
This study explores the process of ice formation in clouds by conducting computer model simulations and laboratory experiments in a cloud chamber. We show that the formation of ice in clouds can be limited by the presence of atmospheric aerosol particles and that further research is required to identify the requirements for freezing, e.g. minimum mass of water, in order to accurately calculate ice formation and thus improve climate and weather prediction.
Yarê Baker, Sungah Kang, Hui Wang, Rongrong Wu, Jian Xu, Annika Zanders, Quanfu He, Thorsten Hohaus, Till Ziehm, Veronica Geretti, Thomas J. Bannan, Simon P. O'Meara, Aristeidis Voliotis, Mattias Hallquist, Gordon McFiggans, Sören R. Zorn, Andreas Wahner, and Thomas Mentel
EGUsphere, https://doi.org/10.5194/egusphere-2023-2402, https://doi.org/10.5194/egusphere-2023-2402, 2023
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Highly oxygenated organic molecules are important contributors to secondary organic aerosol. Their yield depends on detailed atmospheric chemical composition. One important parameter is the ratio of hydroperoxy radicals to organic peroxy radicals (HO2/RO2) and we show that higher HO2/RO2 ratios lower the secondary organic aerosol yield. This of importance as laboratory studies are often biased towards organic peroxy radicals.
Declan L. Finney, Alan M. Blyth, Martin Gallagher, Huihui Wu, Graeme Nott, Mike Biggerstaff, Richard G. Sonnenfeld, Martin Daily, Dan Walker, David Dufton, Keith Bower, Steven Boeing, Thomas Choularton, Jonathan Crosier, James Groves, Paul R. Field, Hugh Coe, Benjamin J. Murray, Gary Lloyd, Nicholas A. Marsden, Michael Flynn, Kezhen Hu, Naveneeth M. Thamban, Paul I. Williams, James B. McQuaid, Joseph Robinson, Gordon Carrie, Robert Moore, Graydon Aulich, Ralph R. Burton, and Paul J. Connolly
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2023-303, https://doi.org/10.5194/essd-2023-303, 2023
Preprint under review for ESSD
Short summary
Short summary
Deep convective clouds are a source of large uncertainty in predictions of surface temperature response to carbon dioxide. It is the effect of clouds on incoming sunlight and outgoing heat that matters. The DCMEX 2022 campaign in New Mexico collected data with an aircraft, radars, and other instruments. They give new detail on the role of aerosol and cloud ice in cloud formation. Combined with satellite data, the dataset can be used to explore the cloud impact on sunlight and heat.
Rachel L. James, Jonathan Crosier, and Paul J. Connolly
Atmos. Chem. Phys., 23, 9099–9121, https://doi.org/10.5194/acp-23-9099-2023, https://doi.org/10.5194/acp-23-9099-2023, 2023
Short summary
Short summary
Secondary ice production (SIP) may significantly enhance the ice particle concentration in mixed-phase clouds. We present a systematic modelling study of secondary ice formation in idealised shallow convective clouds for various conditions. Our results suggest that the SIP mechanism of collisions of supercooled water drops with more massive ice particles may be a significant ice formation mechanism in shallow convective clouds outside the rime-splintering temperature range (−3 to −8 °C).
Ernesto Reyes-Villegas, Douglas Lowe, Jill S. Johnson, Kenneth S. Carslaw, Eoghan Darbyshire, Michael Flynn, James D. Allan, Hugh Coe, Ying Chen, Oliver Wild, Scott Archer-Nicholls, Alex Archibald, Siddhartha Singh, Manish Shrivastava, Rahul A. Zaveri, Vikas Singh, Gufran Beig, Ranjeet Sokhi, and Gordon McFiggans
Atmos. Chem. Phys., 23, 5763–5782, https://doi.org/10.5194/acp-23-5763-2023, https://doi.org/10.5194/acp-23-5763-2023, 2023
Short summary
Short summary
Organic aerosols (OAs), their sources and their processes remain poorly understood. The volatility basis set (VBS) approach, implemented in air quality models such as WRF-Chem, can be a useful tool to describe primary OA (POA) production and aging. However, the main disadvantage is its complexity. We used a Gaussian process simulator to reproduce model results and to estimate the sources of model uncertainty. We do this by comparing the outputs with OA observations made at Delhi, India, in 2018.
Aristeidis Voliotis, Mao Du, Yu Wang, Yunqi Shao, M. Rami Alfarra, Thomas J. Bannan, Dawei Hu, Kelly L. Pereira, Jaqueline F. Hamilton, Mattias Hallquist, Thomas F. Mentel, and Gordon McFiggans
Atmos. Chem. Phys., 22, 14147–14175, https://doi.org/10.5194/acp-22-14147-2022, https://doi.org/10.5194/acp-22-14147-2022, 2022
Short summary
Short summary
Mixing experiments are crucial and highly beneficial for our understanding of atmospheric chemical interactions. However, interpretation quickly becomes complex, and both the experimental design and evaluation need to be scrutinised carefully. Advanced online and offline compositional measurements can reveal substantial additional information to aid in the interpretation of yield data, including components uniquely found in mixtures and property changes in SOA formed from mixtures of VOCs.
Aristeidis Voliotis, Mao Du, Yu Wang, Yunqi Shao, Thomas J. Bannan, Michael Flynn, Spyros N. Pandis, Carl J. Percival, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 22, 13677–13693, https://doi.org/10.5194/acp-22-13677-2022, https://doi.org/10.5194/acp-22-13677-2022, 2022
Short summary
Short summary
The addition of a low-yield precursor to the reactive mixture of aVOC and bVOC can increase or decrease the SOA volatility that is system-dependent. Therefore, the SOA volatility of the mixtures cannot always be predicted based on the additivity. In complex mixtures the formation of lower-volatility products likely outweighs the formation of products with higher volatility. The unique products of each mixture contribute significantly to the signal, suggesting interactions can be important.
Yunqi Shao, Aristeidis Voliotis, Mao Du, Yu Wang, Kelly Pereira, Jacqueline Hamilton, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 22, 9799–9826, https://doi.org/10.5194/acp-22-9799-2022, https://doi.org/10.5194/acp-22-9799-2022, 2022
Short summary
Short summary
This study explored the chemical properties of secondary organic aerosol (SOA) that formed from photo-oxidation of single and mixed biogenic and anthropogenic precursors. We showed that SOA chemical properties in a mixed vapour system are mainly affected by the
higher-yield precursor's oxidation products and products from
cross-product formation. This study also identifies potential tracer compounds in a mixed vapour system that might be used in SOA source attribution in future ambient studies.
Mao Du, Aristeidis Voliotis, Yunqi Shao, Yu Wang, Thomas J. Bannan, Kelly L. Pereira, Jacqueline F. Hamilton, Carl J. Percival, M. Rami Alfarra, and Gordon McFiggans
Atmos. Meas. Tech., 15, 4385–4406, https://doi.org/10.5194/amt-15-4385-2022, https://doi.org/10.5194/amt-15-4385-2022, 2022
Short summary
Short summary
Atmospheric chemistry plays a key role in the understanding of aerosol formation and air pollution. We designed chamber experiments for the characterization of secondary organic aerosol (SOA) from a biogenic precursor with inorganic seed. Our results highlight the advantages of a combination of online FIGAERO-CIMS and offline LC-Orbitrap MS analytical techniques to characterize the chemical composition of SOA in chamber studies.
Yu Wang, Aristeidis Voliotis, Dawei Hu, Yunqi Shao, Mao Du, Ying Chen, Judith Kleinheins, Claudia Marcolli, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 22, 4149–4166, https://doi.org/10.5194/acp-22-4149-2022, https://doi.org/10.5194/acp-22-4149-2022, 2022
Short summary
Short summary
Aerosol water uptake plays a key role in atmospheric physicochemical processes. We designed chamber experiments on aerosol water uptake of secondary organic aerosol (SOA) from mixed biogenic and anthropogenic precursors with inorganic seed. Our results highlight this chemical composition influences the reconciliation of the sub- and super-saturated water uptake, providing laboratory evidence for understanding the chemical controls of water uptake of the multi-component aerosol.
Jessica Slater, Hugh Coe, Gordon McFiggans, Juha Tonttila, and Sami Romakkaniemi
Atmos. Chem. Phys., 22, 2937–2953, https://doi.org/10.5194/acp-22-2937-2022, https://doi.org/10.5194/acp-22-2937-2022, 2022
Short summary
Short summary
This paper shows the specific impact of black carbon (BC) on the aerosol–planetary boundary layer (PBL) feedback and its influence on a Beijing haze episode. Overall, this paper shows that strong temperature inversions prevent BC heating within the PBL from significantly increasing PBL height, while BC above the PBL suppresses PBL development significantly through the day. From this we suggest a method by which both locally and regionally emitted BC may impact urban pollution episodes.
Yunqi Shao, Yu Wang, Mao Du, Aristeidis Voliotis, M. Rami Alfarra, Simon P. O'Meara, S. Fiona Turner, and Gordon McFiggans
Atmos. Meas. Tech., 15, 539–559, https://doi.org/10.5194/amt-15-539-2022, https://doi.org/10.5194/amt-15-539-2022, 2022
Short summary
Short summary
A comprehensive description and characterisation of the Manchester Aerosol Chamber (MAC) was conducted. The MAC has good temperature and relative humidity homogeneity, fast mixing times, and comparable losses of gases and particles with other chambers. The MAC's bespoke control system allows improved duty cycles and repeatable experiments. Moreover, the effect of contamination on performance was also investigated. It is highly recommended to regularly track the chamber's performance.
Rachel L. James, Vaughan T. J. Phillips, and Paul J. Connolly
Atmos. Chem. Phys., 21, 18519–18530, https://doi.org/10.5194/acp-21-18519-2021, https://doi.org/10.5194/acp-21-18519-2021, 2021
Short summary
Short summary
Secondary ice production (SIP) plays an important role in ice formation within mixed-phase clouds. We present a laboratory investigation of a potentially new SIP mechanism involving the collisions of supercooled water drops with ice particles. At impact, the supercooled water drop fragments form smaller secondary drops. Approximately 30 % of the secondary drops formed during the retraction phase of the supercooled water drop impact freeze over a temperature range of −4 °C to −12 °C.
Aristeidis Voliotis, Yu Wang, Yunqi Shao, Mao Du, Thomas J. Bannan, Carl J. Percival, Spyros N. Pandis, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 21, 14251–14273, https://doi.org/10.5194/acp-21-14251-2021, https://doi.org/10.5194/acp-21-14251-2021, 2021
Short summary
Short summary
Secondary organic aerosol (SOA) formation from mixtures of volatile precursors can be affected by the molecular interactions of the products. Composition and volatility measurements of SOA formed from mixtures of anthropogenic and biogenic precursors reveal processes that can increase or decrease the SOA volatility. The unique products of the mixture were more oxygenated and less volatile than those from either precursor. Analytical context is provided to explore the SOA volatility in mixtures.
Ernesto Reyes-Villegas, Upasana Panda, Eoghan Darbyshire, James M. Cash, Rutambhara Joshi, Ben Langford, Chiara F. Di Marco, Neil J. Mullinger, Mohammed S. Alam, Leigh R. Crilley, Daniel J. Rooney, W. Joe F. Acton, Will Drysdale, Eiko Nemitz, Michael Flynn, Aristeidis Voliotis, Gordon McFiggans, Hugh Coe, James Lee, C. Nicholas Hewitt, Mathew R. Heal, Sachin S. Gunthe, Tuhin K. Mandal, Bhola R. Gurjar, Shivani, Ranu Gadi, Siddhartha Singh, Vijay Soni, and James D. Allan
Atmos. Chem. Phys., 21, 11655–11667, https://doi.org/10.5194/acp-21-11655-2021, https://doi.org/10.5194/acp-21-11655-2021, 2021
Short summary
Short summary
This paper shows the first multisite online measurements of PM1 in Delhi, India, with measurements over different seasons in Old Delhi and New Delhi in 2018. Organic aerosol (OA) source apportionment was performed using positive matrix factorisation (PMF). Traffic was the main primary aerosol source for both OAs and black carbon, seen with PMF and Aethalometer model analysis, indicating that control of primary traffic exhaust emissions would make a significant reduction to Delhi air pollution.
Yu Wang, Aristeidis Voliotis, Yunqi Shao, Taomou Zong, Xiangxinyue Meng, Mao Du, Dawei Hu, Ying Chen, Zhijun Wu, M. Rami Alfarra, and Gordon McFiggans
Atmos. Chem. Phys., 21, 11303–11316, https://doi.org/10.5194/acp-21-11303-2021, https://doi.org/10.5194/acp-21-11303-2021, 2021
Short summary
Short summary
Aerosol phase behaviour plays a profound role in atmospheric physicochemical processes. We designed dedicated chamber experiments to study the phase state of secondary organic aerosol from biogenic and anthropogenic mixed precursors. Our results highlight the key role of the organic–inorganic ratio and relative humidity in phase state, but the sources and organic composition are less important. The result provides solid laboratory evidence for understanding aerosol phase in a complex atmosphere.
Michael Priestley, Thomas J. Bannan, Michael Le Breton, Stephen D. Worrall, Sungah Kang, Iida Pullinen, Sebastian Schmitt, Ralf Tillmann, Einhard Kleist, Defeng Zhao, Jürgen Wildt, Olga Garmash, Archit Mehra, Asan Bacak, Dudley E. Shallcross, Astrid Kiendler-Scharr, Åsa M. Hallquist, Mikael Ehn, Hugh Coe, Carl J. Percival, Mattias Hallquist, Thomas F. Mentel, and Gordon McFiggans
Atmos. Chem. Phys., 21, 3473–3490, https://doi.org/10.5194/acp-21-3473-2021, https://doi.org/10.5194/acp-21-3473-2021, 2021
Short summary
Short summary
A significant fraction of emissions from human activity consists of aromatic hydrocarbons, e.g. benzene, which oxidise to form new compounds important for particle growth. Characterisation of benzene oxidation products highlights the range of species produced as well as their chemical properties and contextualises them within relevant frameworks, e.g. MCM. Cluster analysis of the oxidation product time series distinguishes behaviours of CHON compounds that could aid in identifying functionality.
Simon Patrick O'Meara, Shuxuan Xu, David Topping, M. Rami Alfarra, Gerard Capes, Douglas Lowe, Yunqi Shao, and Gordon McFiggans
Geosci. Model Dev., 14, 675–702, https://doi.org/10.5194/gmd-14-675-2021, https://doi.org/10.5194/gmd-14-675-2021, 2021
Short summary
Short summary
User-friendly and open-source software for simulating aerosol chambers is a valuable tool for research scientists in designing and analysing their experiments. This paper describes a new version of such software and will therefore provide a useful reference for those applying it. Central to the paper is an assessment of the software's accuracy through comparison against previously published simulations.
Jessica Slater, Juha Tonttila, Gordon McFiggans, Paul Connolly, Sami Romakkaniemi, Thomas Kühn, and Hugh Coe
Atmos. Chem. Phys., 20, 11893–11906, https://doi.org/10.5194/acp-20-11893-2020, https://doi.org/10.5194/acp-20-11893-2020, 2020
Short summary
Short summary
The feedback effect between aerosol particles, radiation and meteorology reduces turbulent motion and results in increased surface aerosol concentrations during Beijing haze. Observational analysis and regional modelling studies have examined the feedback effect but these studies are limited. In this work, we set up a high-resolution model for the Beijing environment to examine the sensitivity of the aerosol feedback effect to initial meteorological conditions and aerosol loading.
Yu Wang, Ying Chen, Zhijun Wu, Dongjie Shang, Yuxuan Bian, Zhuofei Du, Sebastian H. Schmitt, Rong Su, Georgios I. Gkatzelis, Patrick Schlag, Thorsten Hohaus, Aristeidis Voliotis, Keding Lu, Limin Zeng, Chunsheng Zhao, M. Rami Alfarra, Gordon McFiggans, Alfred Wiedensohler, Astrid Kiendler-Scharr, Yuanhang Zhang, and Min Hu
Atmos. Chem. Phys., 20, 2161–2175, https://doi.org/10.5194/acp-20-2161-2020, https://doi.org/10.5194/acp-20-2161-2020, 2020
Short summary
Short summary
Severe haze events, with high particulate nitrate (pNO3−) burden, frequently prevail in Beijing. In this study, we demonstrate a mutual-promotion effect between aerosol water uptake and pNO3− formation backed up by theoretical calculations and field observations throughout a typical pNO3−-dominated haze event in Beijing wintertime. This self-amplified mutual-promotion effect between aerosol water content and particulate nitrate can rapidly deteriorate air quality and degrade visibility.
Kathryn Fowler, Paul Connolly, and David Topping
Atmos. Chem. Phys., 20, 683–698, https://doi.org/10.5194/acp-20-683-2020, https://doi.org/10.5194/acp-20-683-2020, 2020
Short summary
Short summary
Observations of low–temperature cirrus clouds have found unexpectedly low ice crystal numbers and high supersaturations, suggesting an incomplete understanding of the freezing mechanisms under these conditions. The existence of viscous organic aerosol has offered alternative ice nucleation pathways, which have been observed in laboratory studies. We have developed the first cloud parcel model to investigate the effect of viscosity on ice nucleation.
Olga Garmash, Matti P. Rissanen, Iida Pullinen, Sebastian Schmitt, Oskari Kausiala, Ralf Tillmann, Defeng Zhao, Carl Percival, Thomas J. Bannan, Michael Priestley, Åsa M. Hallquist, Einhard Kleist, Astrid Kiendler-Scharr, Mattias Hallquist, Torsten Berndt, Gordon McFiggans, Jürgen Wildt, Thomas F. Mentel, and Mikael Ehn
Atmos. Chem. Phys., 20, 515–537, https://doi.org/10.5194/acp-20-515-2020, https://doi.org/10.5194/acp-20-515-2020, 2020
Short summary
Short summary
Highly oxygenated organic molecules (HOMs) facilitate aerosol formation in the atmosphere. Using NO3− chemical ionization mass spectrometry we investigated HOM composition and yield in oxidation of aromatic compounds at different reactant concentrations, in the presence of NOx and seed aerosol. Higher OH concentrations increased HOM yield, suggesting multiple oxidation steps, and affected HOM composition, potentially explaining in part discrepancies in published secondary organic aerosol yields.
Ying Chen, Oliver Wild, Edmund Ryan, Saroj Kumar Sahu, Douglas Lowe, Scott Archer-Nicholls, Yu Wang, Gordon McFiggans, Tabish Ansari, Vikas Singh, Ranjeet S. Sokhi, Alex Archibald, and Gufran Beig
Atmos. Chem. Phys., 20, 499–514, https://doi.org/10.5194/acp-20-499-2020, https://doi.org/10.5194/acp-20-499-2020, 2020
Short summary
Short summary
PM2.5 and O3 are two major air pollutants. Some mitigation strategies focusing on reducing PM2.5 may lead to substantial increase in O3. We use statistical emulation combined with atmospheric transport model to perform thousands of sensitivity numerical studies to identify the major sources of PM2.5 and O3 and to develop strategies targeted at both pollutants. Our scientific evidence suggests that regional coordinated emission control is required to mitigate PM2.5 whilst preventing O3 increase.
Jonathan W. Taylor, Sophie L. Haslett, Keith Bower, Michael Flynn, Ian Crawford, James Dorsey, Tom Choularton, Paul J. Connolly, Valerian Hahn, Christiane Voigt, Daniel Sauer, Régis Dupuy, Joel Brito, Alfons Schwarzenboeck, Thierry Bourriane, Cyrielle Denjean, Phil Rosenberg, Cyrille Flamant, James D. Lee, Adam R. Vaughan, Peter G. Hill, Barbara Brooks, Valéry Catoire, Peter Knippertz, and Hugh Coe
Atmos. Chem. Phys., 19, 8503–8522, https://doi.org/10.5194/acp-19-8503-2019, https://doi.org/10.5194/acp-19-8503-2019, 2019
Short summary
Short summary
Low-level clouds cover a wide area of southern West Africa (SWA) and play an important role in the region's climate, reflecting sunlight away from the surface. We performed aircraft measurements of aerosols and clouds over SWA during the 2016 summer monsoon and found pollution, and polluted clouds, across the whole region. Smoke from biomass burning in Central Africa is transported to West Africa, causing a polluted background which limits the effect of local pollution on cloud properties.
Zongbo Shi, Tuan Vu, Simone Kotthaus, Roy M. Harrison, Sue Grimmond, Siyao Yue, Tong Zhu, James Lee, Yiqun Han, Matthias Demuzere, Rachel E. Dunmore, Lujie Ren, Di Liu, Yuanlin Wang, Oliver Wild, James Allan, W. Joe Acton, Janet Barlow, Benjamin Barratt, David Beddows, William J. Bloss, Giulia Calzolai, David Carruthers, David C. Carslaw, Queenie Chan, Lia Chatzidiakou, Yang Chen, Leigh Crilley, Hugh Coe, Tie Dai, Ruth Doherty, Fengkui Duan, Pingqing Fu, Baozhu Ge, Maofa Ge, Daobo Guan, Jacqueline F. Hamilton, Kebin He, Mathew Heal, Dwayne Heard, C. Nicholas Hewitt, Michael Hollaway, Min Hu, Dongsheng Ji, Xujiang Jiang, Rod Jones, Markus Kalberer, Frank J. Kelly, Louisa Kramer, Ben Langford, Chun Lin, Alastair C. Lewis, Jie Li, Weijun Li, Huan Liu, Junfeng Liu, Miranda Loh, Keding Lu, Franco Lucarelli, Graham Mann, Gordon McFiggans, Mark R. Miller, Graham Mills, Paul Monk, Eiko Nemitz, Fionna O'Connor, Bin Ouyang, Paul I. Palmer, Carl Percival, Olalekan Popoola, Claire Reeves, Andrew R. Rickard, Longyi Shao, Guangyu Shi, Dominick Spracklen, David Stevenson, Yele Sun, Zhiwei Sun, Shu Tao, Shengrui Tong, Qingqing Wang, Wenhua Wang, Xinming Wang, Xuejun Wang, Zifang Wang, Lianfang Wei, Lisa Whalley, Xuefang Wu, Zhijun Wu, Pinhua Xie, Fumo Yang, Qiang Zhang, Yanli Zhang, Yuanhang Zhang, and Mei Zheng
Atmos. Chem. Phys., 19, 7519–7546, https://doi.org/10.5194/acp-19-7519-2019, https://doi.org/10.5194/acp-19-7519-2019, 2019
Short summary
Short summary
APHH-Beijing is a collaborative international research programme to study the sources, processes and health effects of air pollution in Beijing. This introduction to the special issue provides an overview of (i) the APHH-Beijing programme, (ii) the measurement and modelling activities performed as part of it and (iii) the air quality and meteorological conditions during joint intensive field campaigns as a core activity within APHH-Beijing.
Thomas J. Bannan, Michael Le Breton, Michael Priestley, Stephen D. Worrall, Asan Bacak, Nicholas A. Marsden, Archit Mehra, Julia Hammes, Mattias Hallquist, M. Rami Alfarra, Ulrich K. Krieger, Jonathan P. Reid, John Jayne, Wade Robinson, Gordon McFiggans, Hugh Coe, Carl J. Percival, and Dave Topping
Atmos. Meas. Tech., 12, 1429–1439, https://doi.org/10.5194/amt-12-1429-2019, https://doi.org/10.5194/amt-12-1429-2019, 2019
Short summary
Short summary
The Filter Inlet for Gases and AEROsols (FIGAERO) is an inlet designed to be coupled with a high-resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS) and provides simultaneous molecular information relating to both the gas- and particle-phase samples. This method has been used to extract vapour pressures of compounds whilst giving quantitative concentrations in the particle phase. Here we detail an ideal set of benchmark compounds for characterization of the FIGAERO.
Dawei Hu, David Topping, and Gordon McFiggans
Atmos. Chem. Phys., 18, 14925–14937, https://doi.org/10.5194/acp-18-14925-2018, https://doi.org/10.5194/acp-18-14925-2018, 2018
Short summary
Short summary
Co-condensation of inorganic or organic vapours on growing droplets could significantly enhance both CCN and cloud droplet number concentration, thereby influencing climate. Until now, there has been very few direct observational evidence of this process. We exposed involatile inorganic particles to a moist atmosphere containing a controlled amount of an organic semi-volatile vapour. We measured a much greater growth of the particles than if they had only been exposed to water vapour.
Matthew Crooks, Paul Connolly, and Gordon McFiggans
Geosci. Model Dev., 11, 3261–3278, https://doi.org/10.5194/gmd-11-3261-2018, https://doi.org/10.5194/gmd-11-3261-2018, 2018
Short summary
Short summary
Clouds form when water condenses onto particles in the atmosphere and the size and chemical composition of these particles can have a large influence over how much water condenses and the subsequent formation of cloud. Additional gases exist in the atmosphere that can condense onto the aerosol particles and change their composition. We present a fast and efficient method of calculating the effect of atmospheric gases on the formation of cloud that can be used in climate and weather models.
Kelly L. Pereira, Rachel Dunmore, James Whitehead, M. Rami Alfarra, James D. Allan, Mohammed S. Alam, Roy M. Harrison, Gordon McFiggans, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 18, 11073–11096, https://doi.org/10.5194/acp-18-11073-2018, https://doi.org/10.5194/acp-18-11073-2018, 2018
Short summary
Short summary
Exhaust emissions from a light-duty diesel engine were introduced into an atmospheric simulation chamber which was used as a holding-cell for sampling, allowing instruments capable of providing detailed chemical speciation of exhaust gas emissions to be used. The effect of different engine conditions on the exhaust gas composition was investigated. The exhaust composition changed considerably due to two influencing factors, engine combustion and diesel oxidative catalyst efficiency.
Robin G. Stevens, Katharina Loewe, Christopher Dearden, Antonios Dimitrelos, Anna Possner, Gesa K. Eirund, Tomi Raatikainen, Adrian A. Hill, Benjamin J. Shipway, Jonathan Wilkinson, Sami Romakkaniemi, Juha Tonttila, Ari Laaksonen, Hannele Korhonen, Paul Connolly, Ulrike Lohmann, Corinna Hoose, Annica M. L. Ekman, Ken S. Carslaw, and Paul R. Field
Atmos. Chem. Phys., 18, 11041–11071, https://doi.org/10.5194/acp-18-11041-2018, https://doi.org/10.5194/acp-18-11041-2018, 2018
Short summary
Short summary
We perform a model intercomparison of summertime high Arctic clouds. Observed concentrations of aerosol particles necessary for cloud formation fell to extremely low values, coincident with a transition from cloudy to nearly cloud-free conditions. Previous analyses have suggested that at these low concentrations, the radiative properties of the clouds are determined primarily by these particle concentrations. The model results strongly support this hypothesis.
Wiebke Frey, Dawei Hu, James Dorsey, M. Rami Alfarra, Aki Pajunoja, Annele Virtanen, Paul Connolly, and Gordon McFiggans
Atmos. Chem. Phys., 18, 9393–9409, https://doi.org/10.5194/acp-18-9393-2018, https://doi.org/10.5194/acp-18-9393-2018, 2018
Short summary
Short summary
The coupled system of the Manchester Aerosol Chamber and Manchester Ice Cloud Chamber was used to study the ice-forming abilities of secondary
organic aerosol particles under mixed-phase cloud conditions. Given the vast abundance of secondary organic particles in the atmosphere, they
might present an important contribution to ice-nucleating particles. However, we find that in the studied temperature range (20 to 28 °C)
the secondary organic particles do not nucleate ice particles.
Emma L. Simpson, Paul J. Connolly, and Gordon McFiggans
Atmos. Chem. Phys., 18, 7237–7250, https://doi.org/10.5194/acp-18-7237-2018, https://doi.org/10.5194/acp-18-7237-2018, 2018
Short summary
Short summary
This study explores the process of ice formation in clouds by conducting computer model simulations and laboratory experiments in a cloud chamber. We show that the formation of ice in clouds can be limited by the presence of atmospheric aerosol particles and that further research is required to identify the requirements for freezing, e.g. minimum mass of water, in order to accurately calculate ice formation and thus improve climate and weather prediction.
Kathryn Fowler, Paul J. Connolly, David O. Topping, and Simon O'Meara
Atmos. Chem. Phys., 18, 1629–1642, https://doi.org/10.5194/acp-18-1629-2018, https://doi.org/10.5194/acp-18-1629-2018, 2018
Short summary
Short summary
This is the first time the Maxwell–Stefan framework has been applied to an atmospheric aerosol core–shell model and shows that there is a complex interplay between the viscous and solubility effects on aerosol composition. Understanding aerosol composition is essential to accurately model their interactions within atmospheric systems. We use simple binary systems to demonstrate how viscosity and solubility both play a role in affecting the rate of diffusion through aerosol particles.
Gillian Young, Paul J. Connolly, Christopher Dearden, and Thomas W. Choularton
Atmos. Chem. Phys., 18, 1475–1494, https://doi.org/10.5194/acp-18-1475-2018, https://doi.org/10.5194/acp-18-1475-2018, 2018
Short summary
Short summary
Large-scale subsidence, associated with high-pressure systems, is often used in cloud-resolving models to maintain the height of boundary layer clouds; however, its influence on the small-scale interactions in mixed-phase clouds has not been previously investigated. Using large-eddy simulations, we have identified a relationship between subsidence and convection development in such clouds, with implications for mixed-phase boundary layer clouds forming in the ocean-exposed Arctic regions.
Olivia Goulden, Matthew Crooks, and Paul Connolly
Atmos. Chem. Phys., 18, 275–287, https://doi.org/10.5194/acp-18-275-2018, https://doi.org/10.5194/acp-18-275-2018, 2018
Short summary
Short summary
The formation of cloud from the condensation of water vapour in the atmosphere on aerosol particles is highly dependent of the chemical properties of the particles. The chemistry is further complicated by the presence of condensible gases in the atmosphere other than water. We provide several methods of including the complicated chemical properties of the aerosol particles and condensing gases into single parameter descriptions, which are suitable for inclusion in large-scale models.
Simon O'Meara, David O. Topping, Rahul A. Zaveri, and Gordon McFiggans
Atmos. Chem. Phys., 17, 10477–10494, https://doi.org/10.5194/acp-17-10477-2017, https://doi.org/10.5194/acp-17-10477-2017, 2017
Short summary
Short summary
To simulate particle-phase diffusion, an analytical expression is desired because it takes less calculation time than a differential equation. Here a correction is found for the analytical solution for when diffusivity is dependent on composition, thereby making it more widely applicable than before. Consequently, we are able to more realistically evaluate the rate limitation (if any) imposed by particle-phase diffusion on component partitioning between the gas and particle phase.
Leonid Nichman, Emma Järvinen, James Dorsey, Paul Connolly, Jonathan Duplissy, Claudia Fuchs, Karoliina Ignatius, Kamalika Sengupta, Frank Stratmann, Ottmar Möhler, Martin Schnaiter, and Martin Gallagher
Atmos. Meas. Tech., 10, 3231–3248, https://doi.org/10.5194/amt-10-3231-2017, https://doi.org/10.5194/amt-10-3231-2017, 2017
Short summary
Short summary
Optical probes are frequently used for the detection of cloud particles. The detected microphysical properties may affect particle growth and accretion mechanisms and the light scattering properties of cirrus clouds. In the CLOUD chamber study at CERN, we compared four optical measurement techniques. We show that shape derivation alone is not sufficient to determine the phase of the small cloud particles. None of the instruments were able to unambiguously determine the phase of small particles.
Huan Yao, Yu Song, Mingxu Liu, Scott Archer-Nicholls, Douglas Lowe, Gordon McFiggans, Tingting Xu, Pin Du, Jianfeng Li, Yusheng Wu, Min Hu, Chun Zhao, and Tong Zhu
Atmos. Chem. Phys., 17, 5205–5219, https://doi.org/10.5194/acp-17-5205-2017, https://doi.org/10.5194/acp-17-5205-2017, 2017
Gillian Young, Paul J. Connolly, Hazel M. Jones, and Thomas W. Choularton
Atmos. Chem. Phys., 17, 4209–4227, https://doi.org/10.5194/acp-17-4209-2017, https://doi.org/10.5194/acp-17-4209-2017, 2017
Short summary
Short summary
Arctic mixed-phase clouds are poorly represented in numerical models, due in part to an overpredicted ice phase. Here, we examine the sensitivity of cloud structure, evolution, and lifetime to modelled primary ice number concentrations over three different surfaces – sea ice, marginal ice, and ocean – to investigate the dependency on both the ice phase and dynamics induced from surface fluxes.
Gillian Young, Hazel M. Jones, Thomas W. Choularton, Jonathan Crosier, Keith N. Bower, Martin W. Gallagher, Rhiannon S. Davies, Ian A. Renfrew, Andrew D. Elvidge, Eoghan Darbyshire, Franco Marenco, Philip R. A. Brown, Hugo M. A. Ricketts, Paul J. Connolly, Gary Lloyd, Paul I. Williams, James D. Allan, Jonathan W. Taylor, Dantong Liu, and Michael J. Flynn
Atmos. Chem. Phys., 16, 13945–13967, https://doi.org/10.5194/acp-16-13945-2016, https://doi.org/10.5194/acp-16-13945-2016, 2016
Short summary
Short summary
Clouds are intricately coupled to the Arctic sea ice. Our inability to accurately model cloud fractions causes large uncertainties in predicted radiative interactions in this region, therefore, affecting sea ice forecasts. Here, we present measurements of cloud microphysics, aerosol properties, and thermodynamic structure over the transition from sea ice to ocean to improve our understanding of the relationship between the Arctic atmosphere and clouds which develop in this region.
François Benduhn, Graham W. Mann, Kirsty J. Pringle, David O. Topping, Gordon McFiggans, and Kenneth S. Carslaw
Geosci. Model Dev., 9, 3875–3906, https://doi.org/10.5194/gmd-9-3875-2016, https://doi.org/10.5194/gmd-9-3875-2016, 2016
Short summary
Short summary
We present a new mathematical formalism that serves to represent exchanges of inorganic matter between the atmosphere gas phase and the aerosol aqueous phase. In a global modelling framework, taking into account these processes may help represent many important features more accurately, such as the formation of cloud droplets or the radiative properties of the atmosphere. The formalism strives to keep an appropriate balance between accuracy and computation efficiency requirements.
Matthew Crooks, Paul Connolly, David Topping, and Gordon McFiggans
Geosci. Model Dev., 9, 3617–3637, https://doi.org/10.5194/gmd-9-3617-2016, https://doi.org/10.5194/gmd-9-3617-2016, 2016
Short summary
Short summary
Semi-volatile compounds, like water, can exist in both vapour phases and condensed phases within a system. This paper presents a method of calculating the condensed and vapour phases of semi-volatile compounds at equilibrium, in particular, when the condensed mass occurs within particles of different sizes and chemical composition. The applications of interest to the authors are those of atmospheric importance such as cloud droplet formation and reflection or absorption of solar radiation.
James D. Whitehead, Eoghan Darbyshire, Joel Brito, Henrique M. J. Barbosa, Ian Crawford, Rafael Stern, Martin W. Gallagher, Paul H. Kaye, James D. Allan, Hugh Coe, Paulo Artaxo, and Gordon McFiggans
Atmos. Chem. Phys., 16, 9727–9743, https://doi.org/10.5194/acp-16-9727-2016, https://doi.org/10.5194/acp-16-9727-2016, 2016
Short summary
Short summary
We present measurements of aerosols during the transition from wet to dry seasons at a pristine rainforest site in central Amazonia. By excluding pollution episodes, we focus on natural biogenic aerosols. Submicron aerosols are dominated by organic material, similar to previous wet season measurements. Larger particles are dominated by biological material, mostly fungal spores, with higher concentrations at night. This study provides important data on the nature of particles above the Amazon.
Scott Archer-Nicholls, Douglas Lowe, David M. Schultz, and Gordon McFiggans
Atmos. Chem. Phys., 16, 5573–5594, https://doi.org/10.5194/acp-16-5573-2016, https://doi.org/10.5194/acp-16-5573-2016, 2016
Short summary
Short summary
The response of the Weather Research and Forecasting model with Chemistry to forcings by biomass burning aerosol were investigated in high-resolution nested domains over Brazil. The aerosol-layer was found to have a negative direct effect at the top of the atmosphere, but this was largely cancelled by a semi-direct effect which inhibited afternoon cloud formation. The cloud response to the aerosol was found to be highly sensitive to model resolution and the use of convective parameterisation.
Simon O'Meara, David O. Topping, and Gordon McFiggans
Atmos. Chem. Phys., 16, 5299–5313, https://doi.org/10.5194/acp-16-5299-2016, https://doi.org/10.5194/acp-16-5299-2016, 2016
Short summary
Short summary
To understand the effect of atmospheric particulate matter on climate and human health we need to know how it evolves. We investigate how best to estimate diffusion of components through particles by comparing diffusion times from three approaches to solving Fick's Law and find that they agree. This means that scientists can simulate Fickian diffusion through atmospheric particles using the approach best suited to their requirements and have confidence that their model is mathematically sound.
Robert J. Farrington, Paul J. Connolly, Gary Lloyd, Keith N. Bower, Michael J. Flynn, Martin W. Gallagher, Paul R. Field, Chris Dearden, and Thomas W. Choularton
Atmos. Chem. Phys., 16, 4945–4966, https://doi.org/10.5194/acp-16-4945-2016, https://doi.org/10.5194/acp-16-4945-2016, 2016
Short summary
Short summary
This paper assesses the reasons for high ice number concentrations observed in orographic clouds by comparing observations with model simulations over Jungfraujoch, Switzerland. The results suggest that ice nuclei do not significantly contribute to the high concentrations and that a surface source of ice crystals is responsible for the witnessed ice number concentrations.
G. Young, H. M. Jones, E. Darbyshire, K. J. Baustian, J. B. McQuaid, K. N. Bower, P. J. Connolly, M. W. Gallagher, and T. W. Choularton
Atmos. Chem. Phys., 16, 4063–4079, https://doi.org/10.5194/acp-16-4063-2016, https://doi.org/10.5194/acp-16-4063-2016, 2016
Leonid Nichman, Claudia Fuchs, Emma Järvinen, Karoliina Ignatius, Niko Florian Höppel, Antonio Dias, Martin Heinritzi, Mario Simon, Jasmin Tröstl, Andrea Christine Wagner, Robert Wagner, Christina Williamson, Chao Yan, Paul James Connolly, James Robert Dorsey, Jonathan Duplissy, Sebastian Ehrhart, Carla Frege, Hamish Gordon, Christopher Robert Hoyle, Thomas Bjerring Kristensen, Gerhard Steiner, Neil McPherson Donahue, Richard Flagan, Martin William Gallagher, Jasper Kirkby, Ottmar Möhler, Harald Saathoff, Martin Schnaiter, Frank Stratmann, and António Tomé
Atmos. Chem. Phys., 16, 3651–3664, https://doi.org/10.5194/acp-16-3651-2016, https://doi.org/10.5194/acp-16-3651-2016, 2016
Short summary
Short summary
Processes in the atmosphere are often governed by the physical and chemical properties of small cloud particles. Ice, water, and mixed clouds, as well as viscous aerosols, were formed under controlled conditions at the CLOUD-CERN facility. The experimental results show a link between cloud particle properties and their unique optical fingerprints. The classification map presented here allows easier discrimination between various particles such as viscous organic aerosol, salt, ice, and liquid.
David Topping, Mark Barley, Michael K. Bane, Nicholas Higham, Bernard Aumont, Nicholas Dingle, and Gordon McFiggans
Geosci. Model Dev., 9, 899–914, https://doi.org/10.5194/gmd-9-899-2016, https://doi.org/10.5194/gmd-9-899-2016, 2016
Short summary
Short summary
In this paper we describe the development and application of a new web-based and open-source facility, UManSysProp (http://umansysprop .seaes.manchester.ac.uk), for automating predictions of molecular and atmospheric aerosol properties. Current facilities include pure component vapour pressures, critical properties, and sub-cooled densities of organic molecules; activity coefficient predictions for mixed inorganic-organic liquid systems; hygroscopic growth factors and CCN activation potential.
I. Crawford, G. Lloyd, E. Herrmann, C. R. Hoyle, K. N. Bower, P. J. Connolly, M. J. Flynn, P. H. Kaye, T. W. Choularton, and M. W. Gallagher
Atmos. Chem. Phys., 16, 2273–2284, https://doi.org/10.5194/acp-16-2273-2016, https://doi.org/10.5194/acp-16-2273-2016, 2016
Short summary
Short summary
In this manuscript we discuss observations of fluorescent aerosol and their interactions with cloud at a high-alpine site in the wintertime under background conditions. We find the majority of the fluorescent aerosol to be consistent in nature to mineral dust and no apparent trend was observed between the fluorescent aerosol fraction and meteorological or cloud microphysical parameters, suggesting that particle fluorescence does not impact cloud evolution or formation at the site.
J. Grazioli, G. Lloyd, L. Panziera, C. R. Hoyle, P. J. Connolly, J. Henneberger, and A. Berne
Atmos. Chem. Phys., 15, 13787–13802, https://doi.org/10.5194/acp-15-13787-2015, https://doi.org/10.5194/acp-15-13787-2015, 2015
Short summary
Short summary
This study investigates the microphysics of winter alpine snowfall occurring in mixed-phase clouds in an inner-Alpine valley during CLACE2014. From polarimetric radar and in situ observations, riming is shown to be an important process leading to more intense snowfall. Riming is usually associated with more intense turbulence providing supercooled liquid water. Distinct features are identified in the vertical structure of polarimetric radar variables.
G. Lloyd, T. W. Choularton, K. N. Bower, M. W. Gallagher, P. J. Connolly, M. Flynn, R. Farrington, J. Crosier, O. Schlenczek, J. Fugal, and J. Henneberger
Atmos. Chem. Phys., 15, 12953–12969, https://doi.org/10.5194/acp-15-12953-2015, https://doi.org/10.5194/acp-15-12953-2015, 2015
Short summary
Short summary
The paper explores the microphysical structure of clouds at the high-alpine measurement site Jungfraujoch, Switzerland. High concentrations of ice crystals were measured by a range of instruments. The presence of these high concentrations could not be explained through conventional understanding of ice formation processes in clouds and the possibility that the surface provides a significant source of ice crystals is investigated.
M. Paramonov, V.-M. Kerminen, M. Gysel, P. P. Aalto, M. O. Andreae, E. Asmi, U. Baltensperger, A. Bougiatioti, D. Brus, G. P. Frank, N. Good, S. S. Gunthe, L. Hao, M. Irwin, A. Jaatinen, Z. Jurányi, S. M. King, A. Kortelainen, A. Kristensson, H. Lihavainen, M. Kulmala, U. Lohmann, S. T. Martin, G. McFiggans, N. Mihalopoulos, A. Nenes, C. D. O'Dowd, J. Ovadnevaite, T. Petäjä, U. Pöschl, G. C. Roberts, D. Rose, B. Svenningsson, E. Swietlicki, E. Weingartner, J. Whitehead, A. Wiedensohler, C. Wittbom, and B. Sierau
Atmos. Chem. Phys., 15, 12211–12229, https://doi.org/10.5194/acp-15-12211-2015, https://doi.org/10.5194/acp-15-12211-2015, 2015
Short summary
Short summary
The research paper presents the first comprehensive overview of field measurements with the CCN Counter performed at a large number of locations around the world within the EUCAARI framework. The paper sheds light on the CCN number concentrations and activated fractions around the world and their dependence on the water vapour supersaturation ratio, the dependence of aerosol hygroscopicity on particle size, and seasonal and diurnal variation of CCN activation and hygroscopic properties.
C. Emersic, P. J. Connolly, S. Boult, M. Campana, and Z. Li
Atmos. Chem. Phys., 15, 11311–11326, https://doi.org/10.5194/acp-15-11311-2015, https://doi.org/10.5194/acp-15-11311-2015, 2015
Short summary
J. D. Allan, P. I. Williams, J. Najera, J. D. Whitehead, M. J. Flynn, J. W. Taylor, D. Liu, E. Darbyshire, L. J. Carpenter, R. Chance, S. J. Andrews, S. C. Hackenberg, and G. McFiggans
Atmos. Chem. Phys., 15, 5599–5609, https://doi.org/10.5194/acp-15-5599-2015, https://doi.org/10.5194/acp-15-5599-2015, 2015
Short summary
Short summary
New particle formation (NPF) is an important contributor to aerosol number concentrations in the Arctic and thus has a major role in dictating cloud properties and climate in this region. Here we present direct evidence that the oxidation of iodine in the atmosphere causes NPF in the Greenland Sea. This is important because this is a NPF mechanism that has not previously been considered in modelling studies at these latitudes.
I. Steinke, C. Hoose, O. Möhler, P. Connolly, and T. Leisner
Atmos. Chem. Phys., 15, 3703–3717, https://doi.org/10.5194/acp-15-3703-2015, https://doi.org/10.5194/acp-15-3703-2015, 2015
Short summary
Short summary
Ice nucleation in clouds has a significant influence on the global radiative budget and the hydrological cycle. Several studies have investigated the ice formation in droplets and parameterizations have been developed in order to include immersion freezing in climate models. In contrast, there are fewer studies regarding the conversion of water vapor into ice (so-called deposition nucleation) which is the topic of this paper which investigates deposition nucleation by Arizona Test dust in detail
G. Lloyd, T. W. Choularton, K. N. Bower, J. Crosier, H. Jones, J. R. Dorsey, M. W. Gallagher, P. Connolly, A. C. R. Kirchgaessner, and T. Lachlan-Cope
Atmos. Chem. Phys., 15, 3719–3737, https://doi.org/10.5194/acp-15-3719-2015, https://doi.org/10.5194/acp-15-3719-2015, 2015
Short summary
Short summary
Measurements of cloud microphysics are reported from the Aerosol-Cloud Coupling And Climate Interactions (ACCACIA) campaign. Concentrations of ice particles from two spring and two summer cases are compared with particular attention to the role of secondary ice in these clouds. In addition aerosol measurements were used as input to a primary ice nucleation parameterisation which was compared with observed values of primary ice in these clouds. We found higher concentrations of ice during summer.
M. D. Jolleys, H. Coe, G. McFiggans, J. W. Taylor, S. J. O'Shea, M. Le Breton, S. J.-B. Bauguitte, S. Moller, P. Di Carlo, E. Aruffo, P. I. Palmer, J. D. Lee, C. J. Percival, and M. W. Gallagher
Atmos. Chem. Phys., 15, 3077–3095, https://doi.org/10.5194/acp-15-3077-2015, https://doi.org/10.5194/acp-15-3077-2015, 2015
Short summary
Short summary
Particulate emissions in the form of organic aerosol from boreal forest fires in Canada have been measured during an aircraft measurement campaign. Ratios of the amount of aerosol emitted relative to gas species such as CO were calculated and show high levels of variability throughout the campaign. This variability is affected by both changes in fire conditions, as fires tended to die down later in the measurement period, and by changes to the aerosol due to chemical reactions in the atmosphere.
S. Archer-Nicholls, D. Lowe, E. Darbyshire, W. T. Morgan, M. M. Bela, G. Pereira, J. Trembath, J. W. Kaiser, K. M. Longo, S. R. Freitas, H. Coe, and G. McFiggans
Geosci. Model Dev., 8, 549–577, https://doi.org/10.5194/gmd-8-549-2015, https://doi.org/10.5194/gmd-8-549-2015, 2015
Short summary
Short summary
The regional WRF-Chem model was used to study aerosol particles from biomass burning in South America. The modelled estimates of fire plume injection heights were found to be too high, with serious implications for modelled aerosol vertical distribution, transport and impacts on local climate. A modified emission scenario was developed which improved the predicted injection height. Model results were compared and evaluated against in situ measurements from the 2012 SAMBBA flight campaign.
D. Lowe, S. Archer-Nicholls, W. Morgan, J. Allan, S. Utembe, B. Ouyang, E. Aruffo, M. Le Breton, R. A. Zaveri, P. Di Carlo, C. Percival, H. Coe, R. Jones, and G. McFiggans
Atmos. Chem. Phys., 15, 1385–1409, https://doi.org/10.5194/acp-15-1385-2015, https://doi.org/10.5194/acp-15-1385-2015, 2015
J. D. Whitehead, M. Irwin, J. D. Allan, N. Good, and G. McFiggans
Atmos. Chem. Phys., 14, 11833–11841, https://doi.org/10.5194/acp-14-11833-2014, https://doi.org/10.5194/acp-14-11833-2014, 2014
Short summary
Short summary
Water uptake of ambient particles was measured by 2 independent techniques at a wide range of locations between 2007 and 2013. The agreement between the techniques was mixed and hence the number of potential cloud seeds calculated from the measurements frequently showed discrepancies. Whilst there is sensitivity to how well we measure the size of the particles, much of the difference depends on how the particles behave when exposed to moisture in the different techniques (and in the atmosphere).
S. Archer-Nicholls, D. Lowe, S. Utembe, J. Allan, R. A. Zaveri, J. D. Fast, Ø. Hodnebrog, H. Denier van der Gon, and G. McFiggans
Geosci. Model Dev., 7, 2557–2579, https://doi.org/10.5194/gmd-7-2557-2014, https://doi.org/10.5194/gmd-7-2557-2014, 2014
M. J. Lawler, J. Whitehead, C. O'Dowd, C. Monahan, G. McFiggans, and J. N. Smith
Atmos. Chem. Phys., 14, 11557–11569, https://doi.org/10.5194/acp-14-11557-2014, https://doi.org/10.5194/acp-14-11557-2014, 2014
Short summary
Short summary
This work describes the chemical and physical characterization of very small (< 100 nm diameter) particles in the marine atmosphere. We show that sea salt is present even at very small sizes and present evidence that organic species are important contributors to apparent new particle formation events over the ocean.
P. J. Connolly, D. O. Topping, F. Malavelle, and G. McFiggans
Atmos. Chem. Phys., 14, 2289–2302, https://doi.org/10.5194/acp-14-2289-2014, https://doi.org/10.5194/acp-14-2289-2014, 2014
M. R. Alfarra, N. Good, K. P. Wyche, J. F. Hamilton, P. S. Monks, A. C. Lewis, and G. McFiggans
Atmos. Chem. Phys., 13, 11769–11789, https://doi.org/10.5194/acp-13-11769-2013, https://doi.org/10.5194/acp-13-11769-2013, 2013
J. F. Hamilton, M. R. Alfarra, N. Robinson, M. W. Ward, A. C. Lewis, G. B. McFiggans, H. Coe, and J. D. Allan
Atmos. Chem. Phys., 13, 11295–11305, https://doi.org/10.5194/acp-13-11295-2013, https://doi.org/10.5194/acp-13-11295-2013, 2013
P. J. Connolly, G. Vaughan, P. Cook, G. Allen, H. Coe, T. W. Choularton, C. Dearden, and A. Hill
Atmos. Chem. Phys., 13, 7133–7152, https://doi.org/10.5194/acp-13-7133-2013, https://doi.org/10.5194/acp-13-7133-2013, 2013
J. Skrotzki, P. Connolly, M. Schnaiter, H. Saathoff, O. Möhler, R. Wagner, M. Niemand, V. Ebert, and T. Leisner
Atmos. Chem. Phys., 13, 4451–4466, https://doi.org/10.5194/acp-13-4451-2013, https://doi.org/10.5194/acp-13-4451-2013, 2013
D. Liu, J. Allan, J. Whitehead, D. Young, M. Flynn, H. Coe, G. McFiggans, Z. L. Fleming, and B. Bandy
Atmos. Chem. Phys., 13, 2015–2029, https://doi.org/10.5194/acp-13-2015-2013, https://doi.org/10.5194/acp-13-2015-2013, 2013
Related subject area
Atmospheric sciences
Comprehensive evaluation of typical planetary boundary layer (PBL) parameterization schemes in China – Part 1: Understanding expressiveness of schemes for different regions from the mechanism perspective
Evaluating 3 decades of precipitation in the Upper Colorado River basin from a high-resolution regional climate model
Implementation of a satellite-based tool for the quantification of CH4 emissions over Europe (AUMIA v1.0) – Part 1: forward modelling evaluation against near-surface and satellite data
The capabilities of the adjoint of GEOS-Chem model to support HEMCO emission inventories and MERRA-2 meteorological data
Rapid O3 assimilations – Part 1: Background and local contributions to tropospheric O3 changes in China in 2015–2020
Description and evaluation of the new UM–UKCA (vn11.0) Double Extended Stratospheric–Tropospheric (DEST vn1.0) scheme for comprehensive modelling of halogen chemistry in the stratosphere
A robust error correction method for numerical weather prediction wind speed based on Bayesian optimization, variational mode decomposition, principal component analysis, and random forest: VMD-PCA-RF (version 1.0.0)
Description and performance of a sectional aerosol microphysical model in the Community Earth System Model (CESM2)
A simplified non-linear chemistry transport model for analyzing NO2 column observations: STILT–NOx
The Hydro-ABC model (Version 2.0): a simplified convective-scale model with moist dynamics
Rapid Adaptive Optimization Model for Atmospheric Chemistry (ROMAC) v1.0
A standardized methodology for the validation of air quality forecast applications (F-MQO): lessons learnt from its application across Europe
Application of the Multi-Scale Infrastructure for Chemistry and Aerosols version 0 (MUSICAv0) for air quality research in Africa
A Regional multi-Air Pollutant Assimilation System (RAPAS v1.0) for emission estimates: system development and application
Evaluation of vertically resolved longwave radiation in SPARTACUS-Urban 0.7.3 and the sensitivity to urban surface temperatures
Key factors for quantitative precipitation nowcasting using ground weather radar data based on deep learning
QES-Plume v1.0: a Lagrangian dispersion model
A two-way coupled regional urban–street network air quality model system for Beijing, China
Simulations of idealised 3D atmospheric flows on terrestrial planets using LFRic-Atmosphere
Emulating lateral gravity wave propagation in a global chemistry–climate model (EMAC v2.55.2) through horizontal flux redistribution
Evaluating WRF-GC v2.0 predictions of boundary layer height and vertical ozone profile during the 2021 TRACER-AQ campaign in Houston, Texas
An optimisation method to improve modelling of wet deposition in atmospheric transport models: applied to FLEXPART v10.4
Modelling concentration heterogeneities in streets using the street-network model MUNICH
Simulation model of Reactive Nitrogen Species in an Urban Atmosphere using a Deep Neural Network: RNDv1.0
J-GAIN v1.1: a flexible tool to incorporate aerosol formation rates obtained by molecular models into large-scale models
Metrics for evaluating the quality in linear atmospheric inverse problems: a case study of a trace gas inversion
Improved representation of volcanic sulfur dioxide depletion in Lagrangian transport simulations: a case study with MPTRAC v2.4
Use of threshold parameter variation for tropical cyclone tracking
Passive-tracer modelling at super-resolution with Weather Research and Forecasting – Advanced Research WRF (WRF-ARW) to assess mass-balance schemes
The High-resolution Intermediate Complexity Atmospheric Research (HICAR v1.1) model enables fast dynamic downscaling to the hectometer scale
A gridded air quality forecast through fusing site-available machine learning predictions from RFSML v1.0 and chemical transport model results from GEOS-Chem v13.1.0 using the ensemble Kalman filter
Implementation and evaluation of updated photolysis rates in the EMEP MSC-W chemical transport model using Cloud-J v7.3e
Plume detection and emission estimate for biomass burning plumes from TROPOMI carbon monoxide observations using APE v1.1
CHEEREIO 1.0: a versatile and user-friendly ensemble-based chemical data assimilation and emissions inversion platform for the GEOS-Chem chemical transport model
A method to derive Fourier–wavelet spectra for the characterization of global-scale waves in the mesosphere and lower thermosphere and its MATLAB and Python software (fourierwavelet v1.1)
Dynamic Meteorology-induced Emissions Coupler (MetEmis) development in the Community Multiscale Air Quality (CMAQ): CMAQ-MetEmis
Visual analysis of model parameter sensitivities along warm conveyor belt trajectories using Met.3D (1.6.0-multivar1)
A global grid model for the estimation of zenith tropospheric delay considering the variations at different altitudes
Simulating heat and CO2 fluxes in Beijing using SUEWS V2020b: sensitivity to vegetation phenology and maximum conductance
A Python library for computing individual and merged non-CO2 algorithmic climate change functions: CLIMaCCF V1.0
The three-dimensional structure of fronts in mid-latitude weather systems in numerical weather prediction models
The development and validation of the Inhomogeneous Wind Scheme for Urban Street (IWSUS-v1)
GPU-HADVPPM V1.0: a high-efficiency parallel GPU design of the piecewise parabolic method (PPM) for horizontal advection in an air quality model (CAMx V6.10)
Variability and combination as an ensemble of mineral dust forecasts during the 2021 CADDIWA experiment using the WRF 3.7.1 and CHIMERE v2020r3 models
Breakups are complicated: an efficient representation of collisional breakup in the superdroplet method
An optimized semi-empirical physical approach for satellite-based PM2.5 retrieval: embedding machine learning to simulate complex physical parameters
Sensitivity of tropospheric ozone to halogen chemistry in the chemistry–climate model LMDZ-INCA vNMHC
Segmentation of XCO2 images with deep learning: application to synthetic plumes from cities and power plants
Evaluating precipitation distributions at regional scales: a benchmarking framework and application to CMIP5 and 6 models
The Fire Inventory from NCAR version 2.5: an updated global fire emissions model for climate and chemistry applications
Wenxing Jia, Xiaoye Zhang, Hong Wang, Yaqiang Wang, Deying Wang, Junting Zhong, Wenjie Zhang, Lei Zhang, Lifeng Guo, Yadong Lei, Jizhi Wang, Yuanqin Yang, and Yi Lin
Geosci. Model Dev., 16, 6635–6670, https://doi.org/10.5194/gmd-16-6635-2023, https://doi.org/10.5194/gmd-16-6635-2023, 2023
Short summary
Short summary
Most current studies on planetary boundary layer (PBL) parameterization schemes are relatively fragmented and lack systematic in-depth analysis and discussion. In this study, we comprehensively evaluate the performance capability of the PBL scheme in five typical regions of China in different seasons from the mechanism of the scheme and the effects of PBL schemes on the near-surface meteorological parameters, vertical structures of the PBL, PBL height, and turbulent diffusion.
William Rudisill, Alejandro Flores, and Rosemary Carroll
Geosci. Model Dev., 16, 6531–6552, https://doi.org/10.5194/gmd-16-6531-2023, https://doi.org/10.5194/gmd-16-6531-2023, 2023
Short summary
Short summary
It is important to know how well atmospheric models do in mountains, but there are not very many weather stations. We evaluate rain and snow from a model from 1987–2020 in the Upper Colorado River basin against the available data. The model works rather well, but there are still some uncertainties in remote locations. We then use snow maps collected by aircraft, streamflow measurements, and some advanced statistics to help identify how well the model works in ways we could not do before.
Angel Liduvino Vara-Vela, Christoffer Karoff, Noelia Rojas Benavente, and Janaina P. Nascimento
Geosci. Model Dev., 16, 6413–6431, https://doi.org/10.5194/gmd-16-6413-2023, https://doi.org/10.5194/gmd-16-6413-2023, 2023
Short summary
Short summary
A 1-year simulation of atmospheric CH4 over Europe is performed and evaluated against observations based on the TROPOspheric Monitoring Instrument (TROPOMI). A good general model–observation agreement is found, with discrepancies reaching their minimum and maximum values during the summer peak season and winter months, respectively. A huge and under-explored potential for CH4 inverse modeling using improved TROPOMI XCH4 data sets in large-scale applications is identified.
Zhaojun Tang, Zhe Jiang, Jiaqi Chen, Panpan Yang, and Yanan Shen
Geosci. Model Dev., 16, 6377–6392, https://doi.org/10.5194/gmd-16-6377-2023, https://doi.org/10.5194/gmd-16-6377-2023, 2023
Short summary
Short summary
We designed a new framework to facilitate emission inventory updates in the adjoint of GEOS-Chem model. It allows us to support Harmonized Emissions Component (HEMCO) emission inventories conveniently and to easily add more emission inventories following future updates in GEOS-Chem forward simulations. Furthermore, we developed new modules to support MERRA-2 meteorological data; this allows us to perform long-term analysis with consistent meteorological data.
Rui Zhu, Zhaojun Tang, Xiaokang Chen, Xiong Liu, and Zhe Jiang
Geosci. Model Dev., 16, 6337–6354, https://doi.org/10.5194/gmd-16-6337-2023, https://doi.org/10.5194/gmd-16-6337-2023, 2023
Short summary
Short summary
A single ozone (O3) tracer mode was developed in this work to build the capability of the GEOS-Chem model for rapid O3 simulation. It is combined with OMI and surface O3 observations to investigate the changes in tropospheric O3 in China in 2015–2020. The assimilations indicate rapid surface O3 increases that are underestimated by the a priori simulations. We find stronger increases in tropospheric O3 columns over polluted areas and a large discrepancy by assimilating different observations.
Ewa M. Bednarz, Ryan Hossaini, N. Luke Abraham, and Martyn P. Chipperfield
Geosci. Model Dev., 16, 6187–6209, https://doi.org/10.5194/gmd-16-6187-2023, https://doi.org/10.5194/gmd-16-6187-2023, 2023
Short summary
Short summary
Development and performance of the new DEST chemistry scheme of UM–UKCA is described. The scheme extends the standard StratTrop scheme by including important updates to the halogen chemistry, thus allowing process-oriented studies of stratospheric ozone depletion and recovery, including impacts from both controlled long-lived ozone-depleting substances and emerging issues around uncontrolled, very short-lived substances. It will thus aid studies in support of future ozone assessment reports.
Shaohui Zhou, Chloe Yuchao Gao, Zexia Duan, Xingya Xi, and Yubin Li
Geosci. Model Dev., 16, 6247–6266, https://doi.org/10.5194/gmd-16-6247-2023, https://doi.org/10.5194/gmd-16-6247-2023, 2023
Short summary
Short summary
The proposed wind speed correction model (VMD-PCA-RF) demonstrates the highest prediction accuracy and stability in the five southern provinces in nearly a year and at different heights. VMD-PCA-RF evaluation indices for 13 months remain relatively stable: the forecasting accuracy rate FA is above 85 %. In future research, the proposed VMD-PCA-RF algorithm can be extrapolated to the 3 km grid points of the five southern provinces to generate a 3 km grid-corrected wind speed product.
Simone Tilmes, Michael J. Mills, Yunqian Zhu, Charles G. Bardeen, Francis Vitt, Pengfei Yu, David Fillmore, Xiaohong Liu, Brian Toon, and Terry Deshler
Geosci. Model Dev., 16, 6087–6125, https://doi.org/10.5194/gmd-16-6087-2023, https://doi.org/10.5194/gmd-16-6087-2023, 2023
Short summary
Short summary
We implemented an alternative aerosol scheme in the high- and low-top model versions of the Community Earth System Model Version 2 (CESM2) with a more detailed description of tropospheric and stratospheric aerosol size distributions than the existing aerosol model. This development enables the comparison of different aerosol schemes with different complexity in the same model framework. It identifies improvements compared to a range of observations in both the troposphere and stratosphere.
Dien Wu, Joshua L. Laughner, Junjie Liu, Paul I. Palmer, John C. Lin, and Paul O. Wennberg
Geosci. Model Dev., 16, 6161–6185, https://doi.org/10.5194/gmd-16-6161-2023, https://doi.org/10.5194/gmd-16-6161-2023, 2023
Short summary
Short summary
To balance computational expenses and chemical complexity in extracting emission signals from tropospheric NO2 columns, we propose a simplified non-linear Lagrangian chemistry transport model and assess its performance against TROPOMI v2 over power plants and cities. Using this model, we then discuss how NOx chemistry affects the relationship between NOx and CO2 emissions and how studying NO2 columns helps quantify modeled biases in wind directions and prior emissions.
Jiangshan Zhu and Ross Noel Bannister
Geosci. Model Dev., 16, 6067–6085, https://doi.org/10.5194/gmd-16-6067-2023, https://doi.org/10.5194/gmd-16-6067-2023, 2023
Short summary
Short summary
We describe how condensation and evaporation are included in the existing (otherwise dry) simplified ABC model. The new model (Hydro-ABC) includes transport of vapour and condensate within a dynamical core, and it transitions between these two phases via a micro-physics scheme. The model shows the development of an anvil cloud and excitation of atmospheric waves over many frequencies. The covariances that develop between variables are also studied together with indicators of convective motion.
Jiangyong Li, Chunlin Zhang, Wenlong Zhao, Shijie Han, Yu Wang, Hao Wang, and Boguang Wang
Geosci. Model Dev., 16, 6049–6066, https://doi.org/10.5194/gmd-16-6049-2023, https://doi.org/10.5194/gmd-16-6049-2023, 2023
Short summary
Short summary
Photochemical box models, crucial for understanding tropospheric chemistry, face challenges due to slow computational efficiency with large chemical equations. The model introduced in this study, ROMAC, boosts efficiency by up to 96 % using an advanced atmospheric solver and an adaptive optimization algorithm. Moreover, ROMAC exceeds traditional box models in evaluating the impact of physical processes on pollutant concentrations.
Lina Vitali, Kees Cuvelier, Antonio Piersanti, Alexandra Monteiro, Mario Adani, Roberta Amorati, Agnieszka Bartocha, Alessandro D'Ausilio, Paweł Durka, Carla Gama, Giulia Giovannini, Stijn Janssen, Tomasz Przybyła, Michele Stortini, Stijn Vranckx, and Philippe Thunis
Geosci. Model Dev., 16, 6029–6047, https://doi.org/10.5194/gmd-16-6029-2023, https://doi.org/10.5194/gmd-16-6029-2023, 2023
Short summary
Short summary
Air quality forecasting models play a key role in fostering short-term measures aimed at reducing human exposure to air pollution. Together with this role comes the need for a thorough assessment of the model performances to build confidence in models’ capabilities, in particular when model applications support policymaking. In this paper, we propose an evaluation methodology and test it on several domains across Europe, highlighting its strengths and room for improvement.
Wenfu Tang, Louisa K. Emmons, Helen M. Worden, Rajesh Kumar, Cenlin He, Benjamin Gaubert, Zhonghua Zheng, Simone Tilmes, Rebecca R. Buchholz, Sara-Eva Martinez-Alonso, Claire Granier, Antonin Soulie, Kathryn McKain, Bruce C. Daube, Jeff Peischl, Chelsea Thompson, and Pieternel Levelt
Geosci. Model Dev., 16, 6001–6028, https://doi.org/10.5194/gmd-16-6001-2023, https://doi.org/10.5194/gmd-16-6001-2023, 2023
Short summary
Short summary
The new MUSICAv0 model enables the study of atmospheric chemistry across all relevant scales. We develop a MUSICAv0 grid for Africa. We evaluate MUSICAv0 with observations and compare it with a previously used model – WRF-Chem. Overall, the performance of MUSICAv0 is comparable to WRF-Chem. Based on model–satellite discrepancies, we find that future field campaigns in an eastern African region (30°E–45°E, 5°S–5°N) could substantially improve the predictive skill of air quality models.
Shuzhuang Feng, Fei Jiang, Zheng Wu, Hengmao Wang, Wei He, Yang Shen, Lingyu Zhang, Yanhua Zheng, Chenxi Lou, Ziqiang Jiang, and Weimin Ju
Geosci. Model Dev., 16, 5949–5977, https://doi.org/10.5194/gmd-16-5949-2023, https://doi.org/10.5194/gmd-16-5949-2023, 2023
Short summary
Short summary
We document the system development and application of a Regional multi-Air Pollutant Assimilation System (RAPAS v1.0). This system is developed to optimize gridded source emissions of CO, SO2, NOx, primary PM2.5, and coarse PM10 on a regional scale via simultaneously assimilating surface measurements of CO, SO2, NO2, PM2.5, and PM10. A series of sensitivity experiments demonstrates the advantage of the “two-step” inversion strategy and the robustness of the system in estimating the emissions.
Megan A. Stretton, William Morrison, Robin J. Hogan, and Sue Grimmond
Geosci. Model Dev., 16, 5931–5947, https://doi.org/10.5194/gmd-16-5931-2023, https://doi.org/10.5194/gmd-16-5931-2023, 2023
Short summary
Short summary
Cities' materials and forms impact radiative fluxes. We evaluate the SPARTACUS-Urban multi-layer approach to modelling longwave radiation, describing realistic 3D geometry statistically using the explicit DART (Discrete Anisotropic Radiative Transfer) model. The temperature configurations used are derived from thermal camera observations. SPARTACUS-Urban accurately predicts longwave fluxes, with a low computational time (cf. DART), but has larger errors with sunlit/shaded surface temperatures.
Daehyeon Han, Jungho Im, Yeji Shin, and Juhyun Lee
Geosci. Model Dev., 16, 5895–5914, https://doi.org/10.5194/gmd-16-5895-2023, https://doi.org/10.5194/gmd-16-5895-2023, 2023
Short summary
Short summary
To identify the key factors affecting quantitative precipitation nowcasting (QPN) using deep learning (DL), we carried out a comprehensive evaluation and analysis. We compared four key factors: DL model, length of the input sequence, loss function, and ensemble approach. Generally, U-Net outperformed ConvLSTM. Loss function and ensemble showed potential for improving performance when they synergized well. The length of the input sequence did not significantly affect the results.
Fabien Margairaz, Balwinder Singh, Jeremy A. Gibbs, Loren Atwood, Eric R. Pardyjak, and Rob Stoll
Geosci. Model Dev., 16, 5729–5754, https://doi.org/10.5194/gmd-16-5729-2023, https://doi.org/10.5194/gmd-16-5729-2023, 2023
Short summary
Short summary
The Quick Environmental Simulation (QES) tool is a low-computational-cost fast-response framework. It provides high-resolution wind and concentration information to study complex problems, such as spore or smoke transport, urban pollution, and air quality. This paper presents the particle dispersion model and its validation against analytical solutions and wind-tunnel data for a mock-urban setting. In all cases, the model provides accurate results with competitive computational performance.
Tao Wang, Hang Liu, Jie Li, Shuai Wang, Youngseob Kim, Yele Sun, Wenyi Yang, Huiyun Du, Zhe Wang, and Zifa Wang
Geosci. Model Dev., 16, 5585–5599, https://doi.org/10.5194/gmd-16-5585-2023, https://doi.org/10.5194/gmd-16-5585-2023, 2023
Short summary
Short summary
This paper developed a two-way coupled module in a new version of a regional urban–street network model, IAQMS-street v2.0, in which the mass flux from streets to background is considered. Test cases are defined to evaluate the performance of IAQMS-street v2.0 in Beijing by comparing it with that simulated by IAQMS-street v1.0 and a regional model. The contribution of local emissions and the influence of on-road vehicle control measures on air quality are evaluated by using IAQMS-street v2.0.
Denis E. Sergeev, Nathan J. Mayne, Thomas Bendall, Ian A. Boutle, Alex Brown, Iva Kavčič, James Kent, Krisztian Kohary, James Manners, Thomas Melvin, Enrico Olivier, Lokesh K. Ragta, Ben Shipway, Jon Wakelin, Nigel Wood, and Mohamed Zerroukat
Geosci. Model Dev., 16, 5601–5626, https://doi.org/10.5194/gmd-16-5601-2023, https://doi.org/10.5194/gmd-16-5601-2023, 2023
Short summary
Short summary
Three-dimensional climate models are one of the best tools we have to study planetary atmospheres. Here, we apply LFRic-Atmosphere, a new model developed by the Met Office, to seven different scenarios for terrestrial planetary climates, including four for the exoplanet TRAPPIST-1e, a primary target for future observations. LFRic-Atmosphere reproduces these scenarios within the spread of the existing models across a range of key climatic variables, justifying its use in future exoplanet studies.
Roland Eichinger, Sebastian Rhode, Hella Garny, Peter Preusse, Petr Pisoft, Aleš Kuchař, Patrick Jöckel, Astrid Kerkweg, and Bastian Kern
Geosci. Model Dev., 16, 5561–5583, https://doi.org/10.5194/gmd-16-5561-2023, https://doi.org/10.5194/gmd-16-5561-2023, 2023
Short summary
Short summary
The columnar approach of gravity wave (GW) schemes results in dynamical model biases, but parallel decomposition makes horizontal GW propagation computationally unfeasible. In the global model EMAC, we approximate it by GW redistribution at one altitude using tailor-made redistribution maps generated with a ray tracer. More spread-out GW drag helps reconcile the model with observations and close the 60°S GW gap. Polar vortex dynamics are improved, enhancing climate model credibility.
Xueying Liu, Yuxuan Wang, Shailaja Wasti, Wei Li, Ehsan Soleimanian, James Flynn, Travis Griggs, Sergio Alvarez, John T. Sullivan, Maurice Roots, Laurence Twigg, Guillaume Gronoff, Timothy Berkoff, Paul Walter, Mark Estes, Johnathan W. Hair, Taylor Shingler, Amy Jo Scarino, Marta Fenn, and Laura Judd
Geosci. Model Dev., 16, 5493–5514, https://doi.org/10.5194/gmd-16-5493-2023, https://doi.org/10.5194/gmd-16-5493-2023, 2023
Short summary
Short summary
With a comprehensive suite of ground-based and airborne remote sensing measurements during the 2021 TRacking Aerosol Convection ExpeRiment – Air Quality (TRACER-AQ) campaign in Houston, this study evaluates the simulation of the planetary boundary layer (PBL) height and the ozone vertical profile by a high-resolution (1.33 km) 3-D photochemical model Weather Research and Forecasting-driven GEOS-Chem (WRF-GC).
Stijn Van Leuven, Pieter De Meutter, Johan Camps, Piet Termonia, and Andy Delcloo
Geosci. Model Dev., 16, 5323–5338, https://doi.org/10.5194/gmd-16-5323-2023, https://doi.org/10.5194/gmd-16-5323-2023, 2023
Short summary
Short summary
Precipitation collects airborne particles and deposits these on the ground. This process is called wet deposition and greatly determines how airborne radioactive particles (released routinely or accidentally) contaminate the surface. In this work we present a new method to improve the calculation of wet deposition in computer models. We apply this method to the existing model FLEXPART by simulating the Fukushima nuclear accident (2011) and show that it improves the simulation of wet deposition.
Thibaud Sarica, Alice Maison, Yelva Roustan, Matthias Ketzel, Steen Solvang Jensen, Youngseob Kim, Christophe Chaillou, and Karine Sartelet
Geosci. Model Dev., 16, 5281–5303, https://doi.org/10.5194/gmd-16-5281-2023, https://doi.org/10.5194/gmd-16-5281-2023, 2023
Short summary
Short summary
A new version of the Model of Urban Network of Intersecting Canyons and Highways (MUNICH) is developed to represent heterogeneities of concentrations in streets. The street volume is discretized vertically and horizontally to limit the artificial dilution of emissions and concentrations. This new version is applied to street networks in Copenhagen and Paris. The comparisons to observations are improved, with higher concentrations of pollutants emitted by traffic at the bottom of the street.
Junsu Gil, Meehye Lee, Jeonghwan Kim, Gangwoong Lee, Joonyoung Ahn, and Cheol-Hee Kim
Geosci. Model Dev., 16, 5251–5263, https://doi.org/10.5194/gmd-16-5251-2023, https://doi.org/10.5194/gmd-16-5251-2023, 2023
Short summary
Short summary
In this study, the framework for calculating reactive nitrogen species using a deep neural network (RND) was developed. It works through simple Python codes and provides high-accuracy reactive nitrogen oxide data. In the first version (RNDv1.0), the model calculates the nitrous acid (HONO) in urban areas, which has an important role in producing O3 and fine aerosol.
Daniel Yazgi and Tinja Olenius
Geosci. Model Dev., 16, 5237–5249, https://doi.org/10.5194/gmd-16-5237-2023, https://doi.org/10.5194/gmd-16-5237-2023, 2023
Short summary
Short summary
We present flexible tools to implement aerosol formation rate predictions in climate and chemical transport models. New-particle formation is a significant but uncertain factor affecting aerosol numbers and an active field within molecular modeling which provides data for assessing formation rates for different chemical species. We introduce tools to generate and interpolate formation rate lookup tables for user-defined data, thus enabling the easy inclusion and testing of formation schemes.
Vineet Yadav, Subhomoy Ghosh, and Charles E. Miller
Geosci. Model Dev., 16, 5219–5236, https://doi.org/10.5194/gmd-16-5219-2023, https://doi.org/10.5194/gmd-16-5219-2023, 2023
Short summary
Short summary
Measuring the performance of inversions in linear Bayesian problems is crucial in real-life applications. In this work, we provide analytical forms of the local and global sensitivities of the estimated fluxes with respect to various inputs. We provide methods to uniquely map the observational signal to spatiotemporal domains. Utilizing this, we also show techniques to assess correlations between the Jacobians that naturally translate to nonstationary covariance matrix components.
Mingzhao Liu, Lars Hoffmann, Sabine Griessbach, Zhongyin Cai, Yi Heng, and Xue Wu
Geosci. Model Dev., 16, 5197–5217, https://doi.org/10.5194/gmd-16-5197-2023, https://doi.org/10.5194/gmd-16-5197-2023, 2023
Short summary
Short summary
We introduce new and revised chemistry and physics modules in the Massive-Parallel Trajectory Calculations (MPTRAC) Lagrangian transport model aiming to improve the representation of volcanic SO2 transport and depletion. We test these modules in a case study of the Ambae eruption in July 2018 in which the SO2 plume underwent wet removal and convection. The lifetime of SO2 shows highly variable and complex dependencies on the atmospheric conditions at different release heights.
Bernhard M. Enz, Jan P. Engelmann, and Ulrike Lohmann
Geosci. Model Dev., 16, 5093–5112, https://doi.org/10.5194/gmd-16-5093-2023, https://doi.org/10.5194/gmd-16-5093-2023, 2023
Short summary
Short summary
An algorithm to track tropical cyclones in model simulation data has been developed. The algorithm uses many combinations of varying parameter thresholds to detect weaker phases of tropical cyclones while still being resilient to false positives. It is shown that the algorithm performs well and adequately represents the tropical cyclone activity of the underlying simulation data. The impact of false positives on overall tropical cyclone activity is shown to be insignificant.
Sepehr Fathi, Mark Gordon, and Yongsheng Chen
Geosci. Model Dev., 16, 5069–5091, https://doi.org/10.5194/gmd-16-5069-2023, https://doi.org/10.5194/gmd-16-5069-2023, 2023
Short summary
Short summary
We have combined various capabilities within a WRF model to generate simulations of atmospheric pollutant dispersion at 50 m resolution. The study objective was to resolve transport processes at the scale of measurements to assess and optimize aircraft-based emission rate retrievals. Model performance evaluation resulted in agreement within 5 % of observed meteorological and within 1–2 standard deviations of observed wind fields. Mass was conserved in the model within 5 % of input emissions.
Dylan Reynolds, Ethan Gutmann, Bert Kruyt, Michael Haugeneder, Tobias Jonas, Franziska Gerber, Michael Lehning, and Rebecca Mott
Geosci. Model Dev., 16, 5049–5068, https://doi.org/10.5194/gmd-16-5049-2023, https://doi.org/10.5194/gmd-16-5049-2023, 2023
Short summary
Short summary
The challenge of running geophysical models is often compounded by the question of where to obtain appropriate data to give as input to a model. Here we present the HICAR model, a simplified atmospheric model capable of running at spatial resolutions of hectometers for long time series or over large domains. This makes physically consistent atmospheric data available at the spatial and temporal scales needed for some terrestrial modeling applications, for example seasonal snow forecasting.
Li Fang, Jianbing Jin, Arjo Segers, Hong Liao, Ke Li, Bufan Xu, Wei Han, Mijie Pang, and Hai Xiang Lin
Geosci. Model Dev., 16, 4867–4882, https://doi.org/10.5194/gmd-16-4867-2023, https://doi.org/10.5194/gmd-16-4867-2023, 2023
Short summary
Short summary
Machine learning models have gained great popularity in air quality prediction. However, they are only available at air quality monitoring stations. In contrast, chemical transport models (CTM) provide predictions that are continuous in the 3D field. Owing to complex error sources, they are typically biased. In this study, we proposed a gridded prediction with high accuracy by fusing predictions from our regional feature selection machine learning prediction (RFSML v1.0) and a CTM prediction.
Willem Elias van Caspel, David Simpson, Jan Eiof Jonson, Anna Maria Katarina Benedictow, Yao Ge, Alcide di Sarra, Giandomenico Pace, Massimo Vieno, Hannah Walker, and Mathew Heal
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2023-147, https://doi.org/10.5194/gmd-2023-147, 2023
Revised manuscript accepted for GMD
Short summary
Short summary
Radiation coming from the sun is essential to atmospheric chemistry, driving the break-up, or photo-dissociation, of atmospheric molecules. This in turn affects the chemical composition and reactivity of the atmosphere. The representation of these photo-dissociation effects is therefore essential in atmospheric chemistry modeling. One such models is the EMEP MSC-W model, for which in this paper a new way of calculating the photo-dissociation rates is tested and evaluated.
Manu Goudar, Juliëtte C. S. Anema, Rajesh Kumar, Tobias Borsdorff, and Jochen Landgraf
Geosci. Model Dev., 16, 4835–4852, https://doi.org/10.5194/gmd-16-4835-2023, https://doi.org/10.5194/gmd-16-4835-2023, 2023
Short summary
Short summary
A framework was developed to automatically detect plumes and compute emission estimates with cross-sectional flux method (CFM) for biomass burning events in TROPOMI CO datasets using Visible Infrared Imaging Radiometer Suite active fire data. The emissions were more reliable when changing plume height in downwind direction was used instead of constant injection height. The CFM had uncertainty even when the meteorological conditions were accurate; thus there is a need for better inversion models.
Drew C. Pendergrass, Daniel J. Jacob, Hannah Nesser, Daniel J. Varon, Melissa Sulprizio, Kazuyuki Miyazaki, and Kevin W. Bowman
Geosci. Model Dev., 16, 4793–4810, https://doi.org/10.5194/gmd-16-4793-2023, https://doi.org/10.5194/gmd-16-4793-2023, 2023
Short summary
Short summary
We have built a tool called CHEEREIO that allows scientists to use observations of pollutants or gases in the atmosphere, such as from satellites or surface stations, to update supercomputer models that simulate the Earth. CHEEREIO uses the difference between the model simulations of the atmosphere and real-world observations to come up with a good guess for the actual composition of our atmosphere, the true emissions of various pollutants, and whatever else they may want to study.
Yosuke Yamazaki
Geosci. Model Dev., 16, 4749–4766, https://doi.org/10.5194/gmd-16-4749-2023, https://doi.org/10.5194/gmd-16-4749-2023, 2023
Short summary
Short summary
The Earth's atmosphere can support various types of global-scale waves. Some waves propagate eastward and others westward, and they can have different zonal wavenumbers. The Fourier–wavelet analysis is a useful technique for identifying different components of global-scale waves and their temporal variability. This paper introduces an easy-to-implement method to derive Fourier–wavelet spectra from 2-D space–time data. Application examples are presented using atmospheric models.
Bok H. Baek, Carlie Coats, Siqi Ma, Chi-Tsan Wang, Yunyao Li, Jia Xing, Daniel Tong, Soontae Kim, and Jung-Hun Woo
Geosci. Model Dev., 16, 4659–4676, https://doi.org/10.5194/gmd-16-4659-2023, https://doi.org/10.5194/gmd-16-4659-2023, 2023
Short summary
Short summary
To enable the direct feedback effects of aerosols and local meteorology in an air quality modeling system without any computational bottleneck, we have developed an inline meteorology-induced emissions coupler module within the U.S. Environmental Protection Agency’s Community Multiscale Air Quality modeling system to dynamically model the complex MOtor Vehicle Emission Simulator (MOVES) on-road mobile emissions inline without a separate dedicated emissions processing model like SMOKE.
Christoph Neuhauser, Maicon Hieronymus, Michael Kern, Marc Rautenhaus, Annika Oertel, and Rüdiger Westermann
Geosci. Model Dev., 16, 4617–4638, https://doi.org/10.5194/gmd-16-4617-2023, https://doi.org/10.5194/gmd-16-4617-2023, 2023
Short summary
Short summary
Numerical weather prediction models rely on parameterizations for sub-grid-scale processes, which are a source of uncertainty. We present novel visual analytics solutions to analyze interactively the sensitivities of a selected prognostic variable to multiple model parameters along trajectories regarding similarities in temporal development and spatiotemporal relationships. The proposed workflow is applied to cloud microphysical sensitivities along coherent strongly ascending trajectories.
Liangke Huang, Shengwei Lan, Ge Zhu, Fade Chen, Junyu Li, and Lilong Liu
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2023-139, https://doi.org/10.5194/gmd-2023-139, 2023
Revised manuscript accepted for GMD
Short summary
Short summary
The existing ZTD models have limitations such as using a single fitting function, neglecting daily cycle variations, and relying on only one resolution grid data for modeling. This model considers the daily-cycle variation and latitude factor of ZTD, using the sliding window algorithm based on ERA5 atmospheric reanalysis data. The ZTD data from 545 radiosonde stations and MERRA-2 atmospheric reanalysis data are used to validate the accuracy of the GGZTD-P model.
Yingqi Zheng, Minttu Havu, Huizhi Liu, Xueling Cheng, Yifan Wen, Hei Shing Lee, Joyson Ahongshangbam, and Leena Järvi
Geosci. Model Dev., 16, 4551–4579, https://doi.org/10.5194/gmd-16-4551-2023, https://doi.org/10.5194/gmd-16-4551-2023, 2023
Short summary
Short summary
The performance of the Surface Urban Energy and Water Balance Scheme (SUEWS) is evaluated against the observed surface exchanges (fluxes) of heat and carbon dioxide in a densely built neighborhood in Beijing. The heat flux modeling is noticeably improved by using the observed maximum conductance and by optimizing the vegetation phenology modeling. SUEWS also performs well in simulating carbon dioxide flux.
Simone Dietmüller, Sigrun Matthes, Katrin Dahlmann, Hiroshi Yamashita, Abolfazl Simorgh, Manuel Soler, Florian Linke, Benjamin Lührs, Maximilian M. Meuser, Christian Weder, Volker Grewe, Feijia Yin, and Federica Castino
Geosci. Model Dev., 16, 4405–4425, https://doi.org/10.5194/gmd-16-4405-2023, https://doi.org/10.5194/gmd-16-4405-2023, 2023
Short summary
Short summary
Climate-optimized aircraft trajectories avoid atmospheric regions with a large climate impact due to aviation emissions. This requires spatially and temporally resolved information on aviation's climate impact. We propose using algorithmic climate change functions (aCCFs) for CO2 and non-CO2 effects (ozone, methane, water vapor, contrail cirrus). Merged aCCFs combine individual aCCFs by assuming aircraft-specific parameters and climate metrics. Technically this is done with a Python library.
Andreas A. Beckert, Lea Eisenstein, Annika Oertel, Tim Hewson, George C. Craig, and Marc Rautenhaus
Geosci. Model Dev., 16, 4427–4450, https://doi.org/10.5194/gmd-16-4427-2023, https://doi.org/10.5194/gmd-16-4427-2023, 2023
Short summary
Short summary
We investigate the benefit of objective 3-D front detection with modern interactive visual analysis techniques for case studies of extra-tropical cyclones and comparisons of frontal structures between different numerical weather prediction models. The 3-D frontal structures show agreement with 2-D fronts from surface analysis charts and augment them in the vertical dimension. We see great potential for more complex studies of atmospheric dynamics and for operational weather forecasting.
Zhenxin Liu, Yuanhao Chen, Yuhang Wang, Cheng Liu, Shuhua Liu, and Hong Liao
Geosci. Model Dev., 16, 4385–4403, https://doi.org/10.5194/gmd-16-4385-2023, https://doi.org/10.5194/gmd-16-4385-2023, 2023
Short summary
Short summary
The heterogeneous layout of urban buildings leads to the complex wind field in and over the urban canopy. Large discrepancies between the observations and the current simulations result from misunderstanding the character of the wind field. The Inhomogeneous Wind Scheme in Urban Street (IWSUS) was developed to simulate the heterogeneity of the wind speed in a typical street and then improve the simulated energy budget in the lower atmospheric layer over the urban canopy.
Kai Cao, Qizhong Wu, Lingling Wang, Nan Wang, Huaqiong Cheng, Xiao Tang, Dongqing Li, and Lanning Wang
Geosci. Model Dev., 16, 4367–4383, https://doi.org/10.5194/gmd-16-4367-2023, https://doi.org/10.5194/gmd-16-4367-2023, 2023
Short summary
Short summary
Offline performance experiment results show that the GPU-HADVPPM on a V100 GPU can achieve up to 1113.6 × speedups to its original version on an E5-2682 v4 CPU. A series of optimization measures are taken, and the CAMx-CUDA model improves the computing efficiency by 128.4 × on a single V100 GPU card. A parallel architecture with an MPI plus CUDA hybrid paradigm is presented, and it can achieve up to 4.5 × speedup when launching eight CPU cores and eight GPU cards.
Laurent Menut
Geosci. Model Dev., 16, 4265–4281, https://doi.org/10.5194/gmd-16-4265-2023, https://doi.org/10.5194/gmd-16-4265-2023, 2023
Short summary
Short summary
This study analyzes forecasts that were made in 2021 to help trigger measurements during the CADDIWA experiment. The WRF and CHIMERE models were run each day, and the first goal is to quantify the variability of the forecast as a function of forecast leads and forecast location. The possibility of using the different leads as an ensemble is also tested. For some locations, the correlation scores are better with this approach. This could be tested on operational forecast chains in the future.
Emily de Jong, John Ben Mackay, Oleksii Bulenok, Anna Jaruga, and Sylwester Arabas
Geosci. Model Dev., 16, 4193–4211, https://doi.org/10.5194/gmd-16-4193-2023, https://doi.org/10.5194/gmd-16-4193-2023, 2023
Short summary
Short summary
In clouds, collisional breakup occurs when two colliding droplets splinter into new, smaller fragments. Particle-based modeling approaches often do not represent breakup because of the computational demands of creating new droplets. We present a particle-based breakup method that preserves the computational efficiency of these methods. In a series of simple demonstrations, we show that this representation alters cloud processes in reasonable and expected ways.
Caiyi Jin, Qiangqiang Yuan, Tongwen Li, Yuan Wang, and Liangpei Zhang
Geosci. Model Dev., 16, 4137–4154, https://doi.org/10.5194/gmd-16-4137-2023, https://doi.org/10.5194/gmd-16-4137-2023, 2023
Short summary
Short summary
The semi-empirical physical approach derives PM2.5 with strong physical significance. However, due to the complex optical characteristic, the physical parameters are difficult to express accurately. Thus, combining the atmospheric physical mechanism and machine learning, we propose an optimized model. It creatively embeds the random forest model into the physical PM2.5 remote sensing approach to simulate a physical parameter. Our method shows great optimized performance in the validations.
Cyril Caram, Sophie Szopa, Anne Cozic, Slimane Bekki, Carlos A. Cuevas, and Alfonso Saiz-Lopez
Geosci. Model Dev., 16, 4041–4062, https://doi.org/10.5194/gmd-16-4041-2023, https://doi.org/10.5194/gmd-16-4041-2023, 2023
Short summary
Short summary
We studied the role of halogenated compounds (containing chlorine, bromine and iodine), emitted by natural processes (mainly above the oceans), in the chemistry of the lower layers of the atmosphere. We introduced this relatively new chemistry in a three-dimensional climate–chemistry model and looked at how this chemistry will disrupt the ozone. We showed that the concentration of ozone decreases by 22 % worldwide and that of the atmospheric detergent, OH, by 8 %.
Joffrey Dumont Le Brazidec, Pierre Vanderbecken, Alban Farchi, Marc Bocquet, Jinghui Lian, Grégoire Broquet, Gerrit Kuhlmann, Alexandre Danjou, and Thomas Lauvaux
Geosci. Model Dev., 16, 3997–4016, https://doi.org/10.5194/gmd-16-3997-2023, https://doi.org/10.5194/gmd-16-3997-2023, 2023
Short summary
Short summary
Monitoring of CO2 emissions is key to the development of reduction policies. Local emissions, from cities or power plants, may be estimated from CO2 plumes detected in satellite images. CO2 plumes generally have a weak signal and are partially concealed by highly variable background concentrations and instrument errors, which hampers their detection. To address this problem, we propose and apply deep learning methods to detect the contour of a plume in simulated CO2 satellite images.
Min-Seop Ahn, Paul A. Ullrich, Peter J. Gleckler, Jiwoo Lee, Ana C. Ordonez, and Angeline G. Pendergrass
Geosci. Model Dev., 16, 3927–3951, https://doi.org/10.5194/gmd-16-3927-2023, https://doi.org/10.5194/gmd-16-3927-2023, 2023
Short summary
Short summary
We introduce a framework for regional-scale evaluation of simulated precipitation distributions with 62 climate reference regions and 10 metrics and apply it to evaluate CMIP5 and CMIP6 models against multiple satellite-based precipitation products. The common model biases identified in this study are mainly associated with the overestimated light precipitation and underestimated heavy precipitation. These biases persist from earlier-generation models and have been slightly improved in CMIP6.
Christine Wiedinmyer, Yosuke Kimura, Elena C. McDonald-Buller, Louisa K. Emmons, Rebecca R. Buchholz, Wenfu Tang, Keenan Seto, Maxwell B. Joseph, Kelley C. Barsanti, Annmarie G. Carlton, and Robert Yokelson
Geosci. Model Dev., 16, 3873–3891, https://doi.org/10.5194/gmd-16-3873-2023, https://doi.org/10.5194/gmd-16-3873-2023, 2023
Short summary
Short summary
The Fire INventory from NCAR (FINN) provides daily global estimates of emissions from open fires based on satellite detections of hot spots. This version has been updated to apply MODIS and VIIRS satellite fire detection and better represents both large and small fires. FINNv2.5 generates more emissions than FINNv1 and is in general agreement with other fire emissions inventories. The new estimates are consistent with satellite observations, but uncertainties remain regionally and by pollutant.
Cited articles
Abdul-Razzak, H. and Ghan, S. J.: A Parameterization of Aerosol Activation, Part II: Multiple Aerosol Types, J. Geophys. Res., 105, 6837–6844, https://doi.org/10.1029/1999JD901161, 2000.
Abdul-Razzak, H., Ghan, S. J., and Rivera-Carpio, C.: A parameterization of aerosol activation. 1. Single aerosol type, J. Geophys. Res., 103, 6123–6131, 1998.
Albrecht, B. A.: Aerosols, cloud microphysics and fractional cloudiness, Science, 245, 1227–1230, 1989.
Barahona, D., West, R. E. L., Stier, P., Romakkaniemi, S., Kokkola, H., and Nenes, A.: Comprehensively accounting for the effect of giant CCN in cloud activation parameterizations, Atmos. Chem. Phys., 10, 2467–2473, https://doi.org/10.5194/acp-10-2467-2010, 2010.
Connolly, P. J., Emersic, C., and Field, P. R.: A laboratory investigation into the aggregation efficiency of small ice crystals, Atmos. Chem. Phys., 12, 2055–2076, https://doi.org/10.5194/acp-12-2055-2012, 2012.
Connolly, P. J., Topping, D. O., Malavelle, F., and McFiggans, G.: A parameterisation for the activation of cloud drops including the effects of semi-volatile organics, Atmos. Chem. Phys. Discuss., 13, 14447–14475, https://doi.org/10.5194/acpd-13-14447-2013, 2013.
Fountoukis, C. and Nenes, A.: Continued development of a cloud droplet formation parameterization for global climate models, J. Geophys. Res., 110, https://doi.org/10.1029/2004JD005591, erratum, 2005.
Ghan, S. J., Guzman, G., and Abdul-Razzak, H.: Competition between sea salt particles as cloud condensation nulcei, J. Atmos. Sci., 55, 3340–3347, 1998.
Ghan, S. J., Abdul-Razzak, H., Nenes, A., Ming, Y., Xiaohong, L., Ovchinnikov, M., Shipway, B., Meskhidze, N., Xu, J., and Shi, X.: Droplet nucleation: physically-based parameterizations and comparative evaluation, J. Adv. Model. Earth Syst., 3, M10001, https://doi.org/10.1029/2011MS000074, 2011.
Heymsfield, A. J., Johnson, P. N., and Dye, J. E.: Observations of moist adiabatic ascent in Northeast Colorado cumulus congestus clouds, J. Atmos. Sci., 35, 1689–1703, 1978.
Jacobson, M. Z.: Fundamentals of Atmospheric Modelling, Cambridge University Press, 1999.
Miles, R. E., Reid, J. P., and Riipinen, I.: Comparison of approaches for measuring the mass accommodation coefficient for the condensation of water and sensitivities to uncertainties in thermophysical properties, J. Phys. Chem. A, 116, 10810–10825, 2012.
Morales Betancourt, R. and Nenes, A.: Droplet activation parameterization: the population splitting concept revisited, Geosci. Model Dev. Discuss., 7, 2903–2932, https://doi.org/10.5194/gmdd-7-2903-2014, 2014.
Myhre, G., Shindell, D., Bréon, F.-M., Collins, W., Fuglestvedt, J., Huang, J., Koch, D., Lamarque, J.-F., Lee, D., Mendoza, B., Nakajima, T., Robock, A., Stephens, G., Takemura, T., and Zhang, H.: Anthropogenic and Natural Radiative Forcing. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Stocker, T. F., Qin, D., Plattner, G.-K., Tignor, M., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 2013.
Pruppacher, H. R. and Klett, J. D.: Microphysics of Clouds and Precipitation, 2nd Edn., Kluwer Academic Publishers, Boston, 1997.
Sander, R.: Modeling atmospheric chemistry: interactions between gas-phase species and liquid cloud/aerosol particles., Surv. Geophys., 20, 1–31, 1999.
Seinfeld, J. H. and Pandis, S. N.: Atmospheric Chemistry and Physics, John Wiley and Sons, New York, 1998.
Topping, D., Connolly, P., and McFiggans, G.: Cloud droplet number enhanced by co-condensation of organic vapours, Nat. Geosci., 6, 443–446, https://doi.org/10.1038/NGEO1809, 2013.
Twomey, S.: Pollution and the planetary albedo, Atmos. Environ., 8, 1251–1256, 1974.
