About the CALIOPE modelling system
CALIOPE is the air quality forecasting system developed by the Earth Sciences Department at the Barcelona Supercomputing Center (BSC). Thanks to the potential in terms of data processing and analysis provided by supercomputing facilities, CALIOPE offers operational air quality forecasts for the Iberian Peninsula, the city of Barcelona, Catalonia, and Europe, too.
Air quality models are effective tools for predicting and analysing the evolution of air pollutants. A set of software modules forms the CALIOPE modelling system, each devoted to the simulation of specific physical and/or chemical processes that occur in the atmosphere and that affect air quality levels. These modules are combined to return an air quality prediction and are executed in the MareNostrum supercomputer, hosted at the Barcelona Supercomputing Center (BSC).
The CALIOPE modelling system has been providing operational air quality forecasts for different geographical domains since 2008.
CALIOPE provides quantitative and qualitative information about the concentration and dispersal of seven main air pollutants - ozone, nitrogen dioxide, carbon monoxide, sulphur dioxide, particulate matter (PM10 and PM2.5) and benzene - regulated by the European Directive 2008/50/EC and the World Health Organization.
CALIOPE forecasts are routinely performed: a prediction is returned every day showing the most probable air quality conditions over a specific region for the next 48 hours. Air quality forecasts for Europe are provided at a spatial resolution of 12 km x 12 km, whereas they can reach 4 km x 4 km for the Iberian Peninsula and 1 km x 1 km for Catalonia. High-resolution forecasts (20 m x 20 m) are obtained for the city of Barcelona by using the street-level CALIOPE-Urban model.
Software
The CALIOPE modelling system uses different modelling software, each devoted to simulating a specific physical and/or chemical process that occurs in the atmosphere and that affects air quality levels. Modelling software is then combined together and executed in the MareNostrum supercomputer, hosted at the Barcelona Supercomputing Center (BSC-CNS).
- WRFv3.5.1
The Weather Research and Forecasting Model (WRF) is an open-source numerical weather prediction model that simulates meteorological conditions, such as wind, temperature, and vertical mixing. The software is the default meteorological driver of CALIOPE and is supported and maintained by the National Center for Atmospheric Research (USA).
- CMAQv5.0.2
The Community Multiscale Air Quality Modeling System (CMAQ) is an offline and open-source atmospheric chemistry transport model used to predict the diffusion of chemical species influencing weather and atmospheric processes. CMAQ is supported and distributed by the Community Modeling and Analysis System (CMAS) Center.
- HERMESv3
The High-Elective Resolution Modelling Emission System (HERMES) is an open-source and multi-scale atmospheric emission modelling framework that computes anthropogenic gaseous and aerosol emissions for use in atmospheric chemistry models. The model is supported and maintained by the BSC-CNS. The Model of Emissions of Gases and Aerosols from Nature (MEGAN), which is supported and maintained by the University of California, Irvine (UCI), is implemented in the HERMES code for the estimation of the biogenic emissions from terrestrial ecosystems.
- MONARCHv2.0
The Multiscale Online Nonhydrostatic AtmospheRe CHemistry model (MONARCH) is an advanced chemistry and aerosol modelling system representing the atmospheric chemistry cycle, including emission, transport, and deposition along with aerosol–radiation interactions. The dust component simulates and predicts the dust cycle in the atmosphere with the aim of estimating desert dust's contribution to aerosol diffusion. The BSC-CNS supports and maintains the model and provides operational dust forecasts for the World Meteorological Organization Barcelona Dust Regional Center. Since September 2023, MONARCHv2.0 dust forecasts have replaced the previous BSC-DREAM system to represent the dust component in the CALIOPE system.
Note:
For its regional calculations, CALIOPE is initialised using global meteorological data from the Global Forecasting System (GFS) model of the National Centre for Environmental Prediction (NCEP), while boundary conditions for pollutants and aerosols come from the CAMS Global atmospheric composition forecast, operated by the European Centre for Medium-Range Weather Forecasts (ECMWF).
CALIOPE-Urban
CALIOPE-Urban is a modelling tool that estimates the concentration of nitrogen dioxide (NO2) at street level in the city of Barcelona. NO2 and its precursors are mainly emitted by combustion sources such as vehicle engines. Its monitoring is crucial in big cities where traffic is usually congested.
CALIOPE-Urban provides citizens and air quality managers with useful information on how traffic affects the air quality in the neighbourhoods. Such information is essential when designing and applying effective planning and mitigation strategies to protect citizens from air pollution health threats.
To simulate the street-scale NO2 pollution, CALIOPE-Urban uses and combines outputs provided by different modelling software:
- background meteorological and air quality data from the CALIOPE system
- estimates of traffic emissions at the street level from the HERMES model
- geometric information about the urban planning of Barcelona city from the Institut Cartogràfic i Geològic de Catalunya (ICGC) and the Plan Nacional de Ortografía Aérea (PNOA).
Frequently asked questions
Air quality observations are real measurements of the concentration of pollutants in the air obtained from a monitoring instrument. Depending on how far from the instrument's emission sources these measurements are, they display the air pollution over a more or less extended area. For instance, instruments located very close to a trafficked street in the city are called “urban traffic stations” and provide information on the very local air pollution, which may be strongly affected by vehicle exhausts. Conversely, instruments located further away from direct pollution emission sources, for example, in large urban public parks, are called “urban background stations” and provide information on the air pollution affecting the surrounding neighbourhood.
Official air quality monitoring stations have high installation and maintenance costs; hence, only a limited number of them focus on a few harmful chemical species that can be deployed in cities. This means that air quality observations in urban areas are quite dispersed.
Nevertheless, to provide more thorough information on air pollution, scientists rely on air quality modelling systems that mathematically simulate how pollutants disperse in the air. Such modelling systems can be used to generate air quality forecasts.
Air quality forecasts are predictions of the future concentrations of air pollutants expected over the coming days in a specific region. Forecasts are obtained by running air quality modelling systems that use estimations of expected pollutant emissions and meteorological forecasts. In the CALIOPE forecasting system, air quality forecasts are typically calculated hourly for large geographical areas using a spatial resolution of one to a few kilometres. This is why, to be computed, air quality forecasts require huge computational resources.
To produce air quality forecasts, the CALIOPE modelling system uses and combines different models to estimate anthropogenic and biogenic emissions, as well as atmospheric and weather conditions:
- WRFv3.5.1
The Weather Research and Forecasting Model (WRF) is an open-source numerical weather prediction model that simulates meteorological conditions, such as wind, temperature, and vertical mixing. The software is the default meteorological driver of CALIOPE and is supported and maintained by the National Center for Atmospheric Research (USA). - CMAQv5.0.2
The Community Multiscale Air Quality Modeling System (CMAQ) is an offline and open-source atmospheric chemistry transport model used to predict the diffusion of chemical species influencing weather and atmospheric processes. CMAQ is supported and distributed by the Community Modeling and Analysis System (CMAS) Center. - HERMESv3
The High-Elective Resolution Modelling Emission System (HERMES) is an open-source and multi-scale atmospheric emission modelling framework that computes anthropogenic gaseous and aerosol emissions for use in atmospheric chemistry models. The model is supported and maintained by the BSC-CNS. The Model of Emissions of Gases and Aerosols from Nature (MEGAN), which is supported and maintained by the University of California, Irvine (UCI), is implemented in the HERMES code for the estimation of the biogenic emissions from terrestrial ecosystems. - MONARCHv2.0
The Multiscale Online Nonhydrostatic AtmospheRe CHemistry model (MONARCH) is an advanced chemistry and aerosol modelling system representing the atmospheric chemistry cycle, including emission, transport, and deposition along with aerosol–radiation interactions. The dust component simulates and predicts the dust cycle in the atmosphere with the aim of estimating desert dust's contribution to aerosol diffusion. The BSC-CNS supports and maintains the model and provides operational dust forecasts for the World Meteorological Organization Barcelona Dust Regional Center. Since September 2023, MONARCHv2.0 dust forecasts have replaced the previous BSC-DREAM system to represent the dust component in the CALIOPE system.
Note:
For its regional calculations, CALIOPE is initialised using global meteorological data from the Global Forecasting System (GFS) model of the National Centre for Environmental Prediction (NCEP), while boundary conditions for pollutants and aerosols come from the CAMS Global atmospheric composition forecast, operated by the European Centre for Medium-Range Weather Forecasts (ECMWF).
To assess the quality of the results, CALIOPE forecasts are compared with the observed air quality measures obtained by monitoring instruments in the region of interest. For this comparison, the system uses observed data from the European Environment Information and Observation Network (EIONET), which is managed by the European Environment Agency (EEA).
CALIOPE forecasts’ numerical datasets are not available to download from the website. The provision of numerical data or any other type of query that involves adapting our products to the specific needs of users can be accommodated under collaborations in the framework of working contracts or scientific projects. Should you need further information, please contact us through the contact form.
- Images from CALIOPE may be used solely for research, educational, and other not-for-profit purposes. If you link to any content of the CALIOPE website on external web pages, we kindly ask you to inform us through the contact form.
- The CALIOPE team cannot guarantee that the data are correct in all circumstances. We neither accept any liability for any error or omission in the data or any loss or damage arising from its use.
- Articles, papers, or written scientific works of any form based in whole or in part on images or other products supplied by CALIOPE must contain an acknowledgement. Below there is a citation as an example which should be adapted accordingly:
"Images/air quality forecasts are provided by the CALIOPE air quality forecasting system from the Barcelona Supercomputing Center-Centro Nacional de Supercomputación (BSC-CNS).”
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Technical information about the CALIOPE modelling system can be found in the publications list.