Aerosol-Cloud Interactions - A Directed Programme to Reduce Uncertainty in Forcing (ACID-PRUF) through a Targeted Laboratory and Modelling Programme
Lead Research Organisation:
University of Leeds
Department Name: School of Earth and Environment
Abstract
Aerosol particles act as sites for cloud droplet and ice particle formation. Cloud properties can be perturbed through the addition of aerosol particles into the atmosphere from anthropogenic and natural processes. This addition influences cloud microphysical properties, and subsequently affects cloud dynamics and thermodynamics, and the way the cloud interacts with radiation. The Earth's radiation budget is very greatly affected by clouds, and human-induced changes to the particle loading affecting them, known as indirect effects, are large and highly uncertain. A large part of this uncertainty is the result of poor knowledge of the fundamental aerosol and cloud properties and processes, leading to their poor representation in models. A programme of research is proposed here to i) directly investigate these processes in the laboratory, ii) evaluate the sensitivity of climate relevant parameters to the studied processes, iii) interpret the laboratory studies with detailed model investigations and iv) to incorporate and test new descriptions of the studied processes in cloud-scale and, where possible, global scale models. The programme will thereby reduce the uncertainty in estimates of radiative forcing and climate feedbacks relating to aerosol and cloud processes. The studies are split into those affecting warm clouds (those containing only liquid droplets) and those affecting clouds containing ice particles. The programme brings together an interdisciplinary team of researchers with expertise in 'warm' and 'cold' cloud and aerosol processes combining laboratory and multiscale modelling activities to deliver the improved predictive capability. The 'warm' laboratory work focuses on two major aspects i) the rate at which water is taken up by growing aerosol particles as they become cloud droplets (or 'activate) and ii) the ability of aerosol particles of various compositions to act as seeds for cloud droplets. These studies use a number of techniques including single particle optical levitation and investigations in a large photochemical chamber coupled to a large number of chemical and physical probes of ensembles of particles formed in simulated atmospheric chemical processes. The 'cold' work uses a similar coupling of a large, well-instrumented cloud chamber experiments and single particle levitation studies. The chambers used in both aspects will be coupled to investigate the impacts of aerosol transformation conditions on warm and cold cloud formation, using the instrumental payload from both chambers. A range of detailed models will be used to explicitly describe the processes by which aerosol particles interact with increasing relative humidity and reducing temperature to form cloud droplet and ice crystals and to their properties. The processes and properties will be represented in dynamical frameworks to predict the interactions between aerosols and clouds and their radiative effects at cloud resolving scales and radiative forcing of some of the investigated properties on global radiative forcing and feedbacks. The sensitivity of climate relevant parameters to the fundamental parameters investigated in the laboratory programme and their improved quantification will be evaluated using a simplified model 'emulator'.
Organisations
Publications
Hiranuma N
(2015)
A comprehensive laboratory study on the immersion freezing behavior of illite NX particles: a comparison of 17 ice nucleation measurement techniques
in Atmospheric Chemistry and Physics
Sengupta K
(2021)
A global model perturbed parameter ensemble study of secondary organic aerosol formation
in Atmospheric Chemistry and Physics
Wilson TW
(2015)
A marine biogenic source of atmospheric ice-nucleating particles.
in Nature
Whale T
(2015)
A technique for quantifying heterogeneous ice nucleation in microlitre supercooled water droplets
in Atmospheric Measurement Techniques
Regayre L
(2018)
Aerosol and physical atmosphere model parameters are both important sources of uncertainty in aerosol ERF
in Atmospheric Chemistry and Physics
Glassmeier F
(2021)
Aerosol-cloud-climate cooling overestimated by ship-track data.
in Science (New York, N.Y.)
Glassmeier F
(2019)
An emulator approach to stratocumulus susceptibility
in Atmospheric Chemistry and Physics
Glassmeier F
(2019)
An emulator approach to stratocumulus susceptibility
Carslaw K
(2018)
Climate Models Are Uncertain, but We Can Do Something About It
in Eos
Wellmann C
(2020)
Comparing the impact of environmental conditions and microphysics on the forecast uncertainty of deep convective clouds and hail
in Atmospheric Chemistry and Physics
Watson-Parris D
(2020)
Constraining Uncertainty in Aerosol Direct Forcing
in Geophysical Research Letters
Peace A
(2020)
Effect of aerosol radiative forcing uncertainty on projected exceedance year of a 1.5 °C global temperature rise
in Environmental Research Letters
Yoshioka M
(2019)
Ensembles of Global Climate Model Variants Designed for the Quantification and Constraint of Uncertainty in Aerosols and Their Radiative Forcing
in Journal of Advances in Modeling Earth Systems
Park J
(2020)
Environmental Controls on Tropical Sea Breeze Convection and Resulting Aerosol Redistribution
in Journal of Geophysical Research: Atmospheres
Johnson J
(2015)
Evaluating uncertainty in convective cloud microphysics using statistical emulation
in Journal of Advances in Modeling Earth Systems
Butt E
(2017)
Global and regional trends in particulate air pollution and attributable health burden over the past 50 years
in Environmental Research Letters
Mangan TP
(2017)
Heterogeneous Ice Nucleation by Soufriere Hills Volcanic Ash Immersed in Water Droplets.
in PloS one
Umo N
(2015)
Ice nucleation by combustion ash particles at conditions relevant to mixed-phase clouds
in Atmospheric Chemistry and Physics
O'Sullivan D
(2014)
Ice nucleation by fertile soil dusts: relative importance of mineral and biogenic components
in Atmospheric Chemistry and Physics
Whale TF
(2015)
Ice Nucleation Properties of Oxidized Carbon Nanomaterials.
in The journal of physical chemistry letters
Sanchez-Marroquin A
(2020)
Iceland is an episodic source of atmospheric ice-nucleating particles relevant for mixed-phase clouds.
in Science advances
Igel A
(2018)
Meteorological and Land Surface Properties Impacting Sea Breeze Extent and Aerosol Distribution in a Dry Environment
in Journal of Geophysical Research: Atmospheres
Feingold G
(2016)
New approaches to quantifying aerosol influence on the cloud radiative effect.
in Proceedings of the National Academy of Sciences of the United States of America
Harrison A
(2016)
Not all feldspars are equal: a survey of ice nucleating properties across the feldspar group of minerals
in Atmospheric Chemistry and Physics
Price H
(2014)
Quantifying water diffusion in high-viscosity and glassy aqueous solutions using a Raman isotope tracer method
in Atmospheric Chemistry and Physics
Atkinson JD
(2016)
Rate of Homogenous Nucleation of Ice in Supercooled Water.
in The journal of physical chemistry. A
Herbert R
(2014)
Representing time-dependent freezing behaviour in immersion mode ice nucleation
in Atmospheric Chemistry and Physics
Johnson J
(2020)
Robust observational constraint of uncertain aerosol processes and emissions in a climate model and the effect on aerosol radiative forcing
in Atmospheric Chemistry and Physics
Herbert RJ
(2015)
Sensitivity of liquid clouds to homogenous freezing parameterizations.
in Geophysical research letters
Malkin TL
(2015)
Stacking disorder in ice I.
in Physical chemistry chemical physics : PCCP
Murray B
(2015)
The crystal structure of ice under mesospheric conditions
in Journal of Atmospheric and Solar-Terrestrial Physics
Whale TF
(2018)
The enhancement and suppression of immersion mode heterogeneous ice-nucleation by solutes.
in Chemical science
Carslaw K
(2017)
The Global Aerosol Synthesis and Science Project (GASSP): Measurements and Modeling to Reduce Uncertainty
in Bulletin of the American Meteorological Society
McCoy IL
(2020)
The hemispheric contrast in cloud microphysical properties constrains aerosol forcing.
in Proceedings of the National Academy of Sciences of the United States of America
Johnson J
(2018)
The importance of comprehensive parameter sampling and multiple observations for robust constraint of aerosol radiative forcing
in Atmospheric Chemistry and Physics
Atkinson JD
(2013)
The importance of feldspar for ice nucleation by mineral dust in mixed-phase clouds.
in Nature
O'Sullivan D
(2015)
The relevance of nanoscale biological fragments for ice nucleation in clouds.
in Scientific reports
Whale TF
(2017)
The role of phase separation and related topography in the exceptional ice-nucleating ability of alkali feldspars.
in Physical chemistry chemical physics : PCCP
Regayre L
(2020)
The value of remote marine aerosol measurements for constraining radiative forcing uncertainty
in Atmospheric Chemistry and Physics
Murray B
(2015)
Trigonal Ice Crystals in Earth's Atmosphere
in Bulletin of the American Meteorological Society
Description | A detailed model that calculates physical processes in clouds has been used to test whether barriers to the uptake of water vapour onto cloud droplets (described by the accomodation coefficient) makes any difference to the production and development of ice and precipitation particles. Values from the literature were used while waiting for laboratory results being produced in another part of the grant. It was found that the ice and precipitation production and growth was not sensitive to a wide range of values of the accomodation coefficient. |
Exploitation Route | Improved forecasts of all processes involving clouds and global climate models. The results will be used in numerical weather prediction models and global climate models. |
Sectors | Environment |