Stockholm - air quality

The SUDPLAN pilot of Stockholm will develop planning tools for determining air quality, the risks for exceedances of national standards and environmental goals, today and under a future changed climate.

The main objectives are to map air pollutants, control air quality and check the air quality standards, making environmental and health impact assessments in urban planning as well as other activities that need environmental and/or health impact consequence analyses. Other goals are to contribute to research on health and air pollution and provide the public and authorities information on air quality.

The Stockholm pilot is represented by the Stockholm - Uppsala Air Quality Management Association (SULVF)

Coupling of European and local scales

A major part of particulate matter and ozone precursors in Stockholm originates outside of Sweden, from European sources. A nesting of a photochemistry model covering the entire Europe down to a high resolution grid model in the SULVF area, will imply a major step in the possibilities to understand the origins and formulate action plans for mitigation of harmful air pollution.

This is a valid statement for the present air quality situation, but the possibility to also assess future air quality and its response to a changed climate will bring completely new information to city planners in the area. Downscaling from the European scale to the microscale of individual city blocks or streets, is important for assessing the origin of air quality on all scales and to combine climate scenarios with local changes in urban infrastructure.

Effects of climate change

Global climate change is one of the world’s most pressing problems and the City of Stockholm (member of SULFV) has established the goal to be fossil fuel-free by 2050. The biggest challenge is to both increase accessibility and mobility and to minimize harmful climate and environmental effects attributable to the transportation sector. In the energy sector the efforts include energy efficient housing, expansion of district heating and increased used of biofuels.

Of interest is to determine both future air quality in response to climate change effects, maintaining present emissions and land use, and to evaluate the effect on air quality of possible future scenarios of activity patterns, emissions and land use. The changes in land use include the planning of urbanized/industrial/commercial areas, green and forested areas, road/train/boat infrastructure etc.

The most severe health effects come from exposure to ozone and small suspended particles (PM10). Both of these pollutants are, to a major part, originating outside Sweden and transported with the wind from the European continent.

Changing temperature, precipitation and vegetation in Europe will alter the processes behind the formation of ozone and inhalable particulate matter. It is important for the Stockholm administration to regulate local emissions so that a clean and safe air quality can be maintained for present conditions as well as during and after a gradual climate change.

3D high resolution modelling and visualization

Of large interest for SULVF is 3D visualization of grid model and superimposed street canyon concentrations over a 3D city map with building geometries. This type of presentation will help to explain for urban planners and politicians the hot spots of air pollution and how building design, traffic characteristics etc influence this pollution. An improved visualization of different scenarios, will contribute to more effective decisions also for studies of the effect of climate change.

SUDPLAN integrates with the existing air quality management system

The SULVF air quality management system for the Stockholm-Uppsala Metropolitan area is uses the Airviro databases, models and tools and supports the three areas of air quality control and management - measurements, emissions and modeling. The system is used in research and education by Department of Applied Environmental Science at Stockholm University, and model simulations from the system have been the basis for population exposure calculations in several epidemiological studies (in co-operation with Karolinska Institutet and Umeå University) and in other health assessment studies.

The SUDPLAN need for emission data as input to SUDPLAN downscaling models, as well as the the need for monitor data for validation purposes, will be solved by connection to and use of data inside SULVF:s Airviro system.