Swen Metzger

University of Freiburg

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Jos Lelieveld

Cyprus Institute

B. Steil

Max Planck Institute for Chemistry

Klaus Klingmüller

Max Planck Institute for Chemistry

Johannes Flemming

Queen's University

Samuel Rémy

Laboratoires Prod'Hyg (France)

Vincent Huijnen

Royal Netherlands Meteorological Institute

Mohamed Abdelkader

King Abdullah University of Science and Technology

Frank Dentener

Joint Research Centre

Joyce E. Penner

University of Michigan–Ann Arbor

Georgiy Stenchikov

King Abdullah University of Science and Technology

Cooperative Institutions

Max Planck Society

Max Planck Institute for Chemistry

University of Reading

University of Freiburg

Centre National de la Recherche Scientifique

Goddard Space Flight Center

Norwegian Meteorological Institute

Cyprus Institute

Foundation for Research and Technology Hellas

Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)

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The MESSy aerosol submodel MADE3 (v2.0b): description and a box model test

Geoscientific model development (2014)

Christopher Kaiser Johannes Hendricks Mattia Righi Nicole Riemer R. A. Zaveri

Abstract. We introduce MADE3 (Modal Aerosol Dynamics model for Europe, adapted for global applications, 3rd generation; version: MADE3v2.0b), an aerosol dynamics submodel for application within the MESSy framework (Modular Earth Submodel System). MADE3 builds on the predecessor aerosol submodels MADE and MADE-in. Its main new features are the explicit representation of coarse mode particle interactions both with other particles and with condensable gases, and the inclusion of hydrochloric acid (HCl) / chloride (Cl) partitioning between the gas and condensed phases. The aerosol size distribution is represented in the new submodel as a superposition of nine lognormal modes: one for fully soluble particles, one for insoluble particles, and one for mixed particles in each of three size ranges (Aitken, accumulation, and coarse mode size ranges). In order to assess the performance of MADE3 we compare it to its predecessor MADE and to the much more detailed particle-resolved aerosol model PartMC-MOSAIC in a box model simulation of an idealised marine boundary layer test case. MADE3 and MADE results are very similar, except in the coarse mode, where the aerosol is dominated by sea spray particles. Cl is reduced in MADE3 with respect to MADE due to the HCl / Cl partitioning that leads to Cl removal from the sea spray aerosol in our test case. Additionally, the aerosol nitrate concentration is higher in MADE3 due to the condensation of nitric acid on coarse mode particles. MADE3 and PartMC-MOSAIC show substantial differences in the fine particle size distributions (sizes &lesssim; 2 μm) that could be relevant when simulating climate effects on a global scale. Nevertheless, the agreement between MADE3 and PartMC-MOSAIC is very good when it comes to coarse particle size distributions (sizes &gtrsim; 2 μm), and also in terms of aerosol composition. Considering these results and the well-established ability of MADE in reproducing observed aerosol loadings and composition, MADE3 seems suitable for application within a global model.

Particle (ecology)

Mode (computer interface)

10.5194/gmd-7-1137-2014

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Citations (61)

An evaluation of the regional distribution and wet deposition of secondary inorganic aerosols and their gaseous precursors in IFS-COMPO cycle 49R1

Jason Williams Swen Metzger Samuel Rémy Vincent Huijnen Johannes Flemming

Abstract. Secondary Inorganic Aerosol (SIA) constitutes a considerable fraction of total particulate matter exposure, making it an important component of any atmospheric composition and air quality forecasting system. The subsequent loss of SIA to the surface, via both dry and wet deposition, determines the exposure time for humans and the extent of damage imposed on sensitive ecosystems due to increased surface acidity. This study provides a description and evaluation of recent updates to aerosol production, scavenging, and wet deposition processes in the global IFS-COMPO chemical forecasting system, used within the Copernicus Atmosphere Monitoring Service. The implementation of the EQSAM4Clim simplified thermodynamic module in IFS-COMPO cycle 49R1 alters the phase transfer efficiency of SIA precursor gases (sulphur dioxide, nitric acid, and ammonia), which significantly affects particulate SIA concentrations by modifying the fraction converted into aerosol form. Comparisons with surface observational data from Europe, the U.S., and Southeast Asia during 2018 indicate reductions in the global annual mean bias for both sulphates and nitrates. Updating the IFS-COMPO model to cycle 49R1 increases the burden and lifetime of sulphate and ammonium particles by one-third. Coupling EQSAM4Clim with IFS-COMPO improves the representation of ammonia-ammonium partitioning across regions, while the effect on sulphate is minimal. For nitric acid and nitrates, the phase partitioning is also significantly altered, with lower particulate concentrations leading to an excess of gas-phase nitric acid and an associated improvement in surface nitrate predictions. The impact on total regional wet deposition is generally positive, although sulphates in the U.S. and ammonium particles in Southeast Asia are strongly influenced by precursor emission estimates. Overall, these results provide confidence in the ability of IFS-COMPO cycle 49R1 to deliver accurate global-scale deposition fluxes of sulphur and nitrogen.

Deposition

10.5194/gmd-2024-188

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Supplementary material to "Reformulating atmospheric aerosol thermodynamics and hygroscopic growth into haze and clouds"

Swen Metzger Jos Lelieveld

Haze

10.5194/acpd-7-849-2007-supplement

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uniWeather™: Advancing real-time outreach in urban environmental sciences through app and platform

Gregor Feigel Matthias Zeeman Marvin Plein Dirk Schindler Andreas Matzarakis

Research concerning the general public and influencing decision-making necessitates timely dissemination of easily accessible results and data, with a focus on directly verifiable hands-on exploration rather than authoritative assessments in order to raise awareness and engage the public. This applies, for instance, to the high spatial and temporal resolution street-level weather and thermal comfort monitoring network operated in the City of Freiburg. Germany, by the University of Freiburg, to raise awareness for the significant spatial and temporal differences in, e.g., outdoor heat stress patterns in urban areas, which are crucial for informed urban planning and climate resilience.  Addressing this gap, the uniWeather™ app and platform were developed to provide end-users, stakeholder and the general public with free, easily accessible near-real-time data and interpretation. With regard to the FAIR principles, the platform is being developed to support data form other research organisations such as universities, government agencies or companies that operate environmental sensor networks to be provided free of charge. uniWeather™ aims to encourage the sharing and access to data in near real-time by providing an easy-to-integrate service for tailored visualisation and interpretation. In June 2023, the uniWeather™ app and monitoring network were announced in a press release from the University of Freiburg and in a newspaper article providing access to maps and real-time data from 42 street-level weather stations in the Freiburg region within 60 seconds of measurement. The app was readily welcomed by the public, researchers and the city of Freiburg. The project was also well received at public outreach events such as the Eucor-MobiLab Roadshow 2023 in Freiburg (26-30 June 2023) and the exhibition DATEN:RAUM:FREIBURG (4-31 August 2023) of the city of Freiburg. With more than 1.5k users in the first few weeks and continued interest in further functionalities, the platform will be continued and further developed to address the needs of the general public and different scientific communities.

Outreach

Smartphone app

Mobile apps

10.5194/egusphere-egu24-19052

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Combining ENSO Forecasts: A Feasibility Study

Monthly Weather Review (2004)

Swen Metzger Mojib Latif Klaus Fraedrich

Numerical and statistical predictions of simplified models are linearly combined in a sensitivity study to identify the crucial parameters that are needed to enhance predictability of the El Niño–Southern Oscillation (ENSO) phenomenon. The results indicate that the ENSO prediction skill of the simplified models can be improved. The profit achieved strongly depends on the phase information that is utilized by the forecast combination and is inherent in predictions of a quasi-periodic process such as ENSO. The simplest forecast combination that still yields useful forecasts at longer lead times of about half of the ENSO period (18–24 months) is the combination of two persistence forecast schemes. For the prediction period 1982–2003, that is the persistence of a sea surface temperature anomaly (SSTA) index area at 60°S, 180°W and the Niño-3 index SSTA. The level of skill improvement critically depends on the prediction schemes and prediction period, as well as on the period from which the combination weights are derived. Differences between combination forecast and hindcast are minimized if the statistical weights are derived from a time period that is characterized by an ENSO statistic that is close to the prediction period. In this study the prediction period has simply been halved for the sake of simplicity to derive the statistical weights, which is sufficient for predicting the 1980s and 1990s (with each other), but not for predicting, for example, the 1970s. The suppressed 1976/77 El Niño event makes the periodic occurrence less regular compared to the other decades. However, this forecast combination technique can be applied in a much more elaborate way.

Predictability

Statistic

Anomaly (physics)

Hindcast

Forecast verification

Forecast period

Quantitative precipitation forecast

Lead time

10.1175/1520-0493(2004)132<0456:cefafs>2.0.co;2

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Citations (14)

Sensitivity Study of Cross-Atlantic Dust Transport to Dust Emissions, Chemical Aging and Removal Processes and Comparison with Ground and Satellite Data

EGUGA (2016)

Mohamed Abdelkader Swen Metzger Klaus Klingmüller B. Steil Jos Lelieveld

Mineral dust

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Supplementary material to "Aerosol water parameterization: a single parameter framework"

Swen Metzger B. Steil Mohamed Abdelkader K. Klingmüller L. Xu

Ampere

10.5194/acpd-15-33493-2015-supplement

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A computationally efficient parameterization of aerosol, cloud and precipitation pH for application at global and regional scale (EQSAM4Clim-v12)

Geoscientific model development (2024)

Swen Metzger Samuel Rémy J. E. Williams Vincent Huijnen Johannes Flemming

Abstract. The Equilibrium Simplified Aerosol Model for Climate version 12 (EQSAM4Clim-v12) has recently been revised to provide an accurate and efficient method for calculating the acidity of atmospheric particles. EQSAM4Clim is based on an analytical concept that is not only sufficiently fast for chemical weather prediction applications but also free of numerical noise, which also makes it attractive for air quality forecasting. EQSAM4Clim allows the calculation of aerosol composition based on the gas–liquid–solid and the reduced gas–liquid partitioning with the associated water uptake for both cases and can therefore provide important information about the acidity of the aerosols. Here we provide a comprehensive description of the recent changes made to the aerosol acidity parameterization (referred to as a version 12) which builds on the original EQSAM4Clim. We evaluate the pH improvements using a detailed box model and compare them against previous model calculations and both ground-based and aircraft observations from the USA and China, covering different seasons and scenarios. We show that, in most cases, the simulated pH is within reasonable agreement with the reference results of the Extended Aerosol Inorganics Model (E-AIM) and of satisfactory accuracy.

10.5194/gmd-17-5009-2024

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Citations (2)

Gas/aerosol partitioning: 1. A computationally efficient model

Journal of Geophysical Research Atmospheres (2002)

Swen Metzger Frank Dentener Spyros Ν. Pandis Jos Lelieveld

A computationally efficient model to calculate gas/aerosol partitioning of semivolatile inorganic aerosol components has been developed for use in global atmospheric chemistry and climate models. We introduce an approximate method for the activity coefficient calculation that directly relates aerosol activity coefficients to the ambient relative humidity, assuming chemical equilibrium. We demonstrate that this method provides an alternative for the computationally expensive iterative activity coefficient calculation methods presently used in thermodynamic gas/aerosol models. The gain of our method is that the entire system of the gas/aerosol equilibrium partitioning can be solved noniteratively, a substantial advantage in global modeling. We show that our equilibrium simplified aerosol model (EQSAM) yields results similar to those of current state‐of‐the‐art equilibrium models.

10.1029/2001jd001102

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Citations (324)

Improved representation of aerosol acidity in the ECMWF IFS-COMPO 49R1 through the integration of EQSAM4Clim.

Samuel Rémy Swen Metzger Vincent Huijnen Jason Williams Johannes Flemming

The atmospheric composition forecasting system used to produce the CAMS forecasts of global aerosol and trace gases distributions, IFS-COMPO, undergoes periodic upgrades. In this presentation we describe the development of the future operational cycle 49R1, and focus on the implementation of the thermodynamical model EQSAM4Clim version 12 for describing gas-aerosol partitioning processes for nitrate and ammonium and for providing diagnostic aerosol, cloud and precipitation pH values at global scale. This information on aerosol acidity influences tropospheric chemistry processes associated with aqueous phase chemistry and wet deposition. The other updates to cycle 49R1 include modifications to the description of Desert Dust, Sea-salt aerosols, Carbonaceous aerosols and the size description for the calculation of aerosol optics.   The implementation of EQSAM4Clim significantly improves the partitioning of reactive nitrogen compounds decreasing surface concentrations of both nitrate and ammonium, which reduces PM2.5 biases for Europe, U.S. and China, especially during summertime. For aerosol optical depth there is generally a decrease in the simulated biases for wintertime, and for some regions an increase in the bias for summertime. Improvements in the simulated Ångström exponent is noted for almost all regions, resulting in generally a good agreement with observations.    The diagnostic aerosol and precipitation pH calculated by EQSAM4Clim have been compared against results from previous simulations (for aerosol pH) and against ground observations (for precipitation pH), with the temporal distribution in the annual mean values showing good agreement against the regional observational datasets. The use of aerosol acidity only has a relatively smaller impact on the aqueous-phase production of sulphate when compared to the changes in gas-to-particle partitioning brought by the use of EQSAM4Clim.   Metzger, S., Rémy, S., Williams, J. E., Huijnen, V., and Flemming, J.: A revised parameterization for aerosol, cloud and precipitation pH for use in chemical forecasting systems (EQSAM4Clim-v12), EGUsphere [preprint], https://doi.org/10.5194/egusphere-2023-2930, 2023.

Representation

10.5194/egusphere-egu24-12250

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