UISH

What AIR-Portal is

AIR-Portal is an air-quality platform developed by S[&]T (Science [&] Technology, based in Delft, the Netherlands) together with research institutes and European municipalities. It combines satellite observations, land-use data, road and traffic information and ground-station measurements to produce, through a local air-quality model, high-resolution pollutant concentration maps — both historical (analysis) and forecast (up to 3 days).

In the UISH project (Urban Intelligence Science Hub for City Network), AIR-Portal supplies CNR-IFAC with the concentration maps for the city of Catania, which feed the webGIS and the analysis and validation tools of this portal.

Where it has been used

AIR-Portal originates in a Dutch context (S[&]T's example data use Amsterdam) and was designed to be replicated across different European cities. Among the documented application contexts and the end-users connected to the project (source: ESA):

• Catania (Italy) — UISH project, CNR-IFAC × S[&]T Italy;
• Amsterdam and the Netherlands — development and demo data;
• Gemeente Eersel (Netherlands) — end-user connected to the project;
• Airmine AS (Norway) — end-user connected to the project;
• ARPAT, the regional environmental protection agency of Tuscany (Italy) — end-user connected to the project.

Development was also supported by ESA Business Applications, with KNMI (the Dutch meteorological institute) as subcontractor. The UISH project falls under the PON Metropolitan Cities programme (PON METRO).

How the model works

At the core of AIR-Portal is a local air-quality model that downscales the European regional forecasts to the urban scale and corrects them with local measurements. The data sources are largely public services:

• Copernicus CAMS (Copernicus Atmosphere Monitoring Service): regional forecasts and analyses of atmospheric composition, produced by an ensemble of European models, at a resolution of a few kilometres (≈5–10 km);
• Copernicus Land (Copernicus Land Monitoring Service): land-use and land-cover data;
• road network and traffic: proximity to roads and traffic intensity as proxies for local emissions;
• ground stations: observed measurements used for bias correction;
• satellite observations of atmospheric composition.

By combining this information the model brings the coarse CAMS regional field down to street scale, applying a land-use/traffic spatial relationship and a bias correction against the ground stations. The result is a high-resolution grid: nominally 100×100 m, with an hourly time step. For Catania the delivered cells measure about 69×86 m (≈ 2.81″ per side in geographic coordinates).

From data download to the concentration grid

The flow, from the public sources to the grid queried in this portal, is the following:

1. Acquisition of public data (CAMS, Copernicus Land, satellites) and local data (ground stations, traffic).
2. AIR-Portal AQ model: downscaling to the urban scale and bias correction against the observations.
3. Grid generation: hourly and daily concentration grids for each pollutant, plus the AQI index.
4. Delivery to CNR-IFAC via API in standard formats (netCDF and GeoTIFF), with access protected by confidential credentials.
5. Ingestion into a geospatial database (PostgreSQL/PostGIS) and organization into the Catania urban grid, on which the webGIS, the analysis and the model validation rely.

Products and formats

• Pollutants: NO₂, O₃, PM₁₀, PM₂.₅, SO₂ and the air-quality index AQI.
• Temporal resolution: hourly and daily (average).
• Data type: analysis (past) and forecast (up to 3 days).
• Formats: netCDF (.nc) and GeoTIFF (.tiff), open standards supported by most GIS software.

References and documentation

Websites

• S[&]T — Environment & Sustainability / AIR-Portal: stcorp.nl
• AIR-Portal — ESA Business Applications: business.esa.int/projects/air-portal
• Copernicus Atmosphere Monitoring Service (CAMS): atmosphere.copernicus.eu
• Copernicus Land Monitoring Service: land.copernicus.eu
• Copernicus programme: copernicus.eu
• KNMI — Dutch meteorological institute: knmi.nl
• PON Metropolitan Cities programme (PON METRO): ponmetro.it
• netCDF format (Unidata/UCAR): unidata.ucar.edu

Scientific documentation

• Marécal, V. et al. (2015). A regional air quality forecasting system over Europe: the MACC-II daily ensemble production. Geoscientific Model Development, 8, 2777–2813. doi:10.5194/gmd-8-2777-2015 — European regional system (basis of CAMS).
• Inness, A. et al. (2019). The CAMS reanalysis of atmospheric composition. Atmospheric Chemistry and Physics, 19, 3515–3556. doi:10.5194/acp-19-3515-2019
• Hoek, G. et al. (2008). A review of land-use regression models to assess spatial variation of outdoor air pollution. Atmospheric Environment, 42, 7561–7578. doi:10.1016/j.atmosenv.2008.05.057 — land-use methodology for the urban scale.