By planning ahead, citizens can avoide exposure to dangerous concentrations of pollutants
By Cecile Honore, Andrej Klemenc and Anthony Ung
Exposure to high concentrations of air pollutants leads to severe health risks. Children, the elderly and people with respiratory of cardiovascular diseases are especially vulnerable, but preventing high-risk groups from breathing polluted air is easier said than done. Particulate matter, invisible and often odourless, can work its way into our lungs and bloodstreams without our even being aware of it. Even if we manage to obtain information on urban air quality, it is usually too late to change daily schedules, postpone business activities or rearrange visits.
It is commonly presumed that travelling by car--especially modern, roomy cars--prevents occupants from breathing polluted air from outside. Recent scientific research, however, proves otherwise: inside a car, concentrations of air pollutants are actually higher than they are on the road. Nonetheless, motorists are not going to simply stop their cars by the side of the road and walk to their destinations if the radio suddenly broadcasts the alarming news of excessive concentrations of air pollutants.
Air quality forecasts--not just real-time reporting--would give people a chance plan accordingly ahead of time and thereby avoid or reduce exposure to harmful pollutants. Also, building trust with urban populations through scientific verifiability and regularity of air quality monitoring can make citizens far more willing to put up with inconveniences or measures carried out in the interest of preserving public health, such as congestion charges or stricter emissions standards for automobiles. Accurate air quality forecasting might also enable large emitters, such as industrial and municipal heat and/or power plants to gradually reduce their activities over time and make a switch to cleaner--albeit more expensive--fuels, or a combination of both.
A combination of individual and collective measures, including forecasting, is available to help limit exposure to dangerous levels of air pollution. Accurate air quality forecasting is now possible with current measurement capabilities, meteorological data, weather prognosis modelling, local climate modelling, local transport modelling, knowledge of location and time dynamics of air pollution sources, and dispersion modelling. Indeed, some European cities that are already providing air quality forecasting [see below].
CITEAIR II: helping cities
One of the objectives of the recently completed CITEIAR II project was to help cities prepare the way for air quality forecasting by providing accurate but easy to understand information. The CITEAIR approach is based on combined air quality indicators (CAQIs), which not only account for most relevant air polluters but also past pollutant episodes and regional forecasting. The work makes use of the Prevair system's regional forecasting technology but the initial 50x50 km resolution was further increased during CITEAIR to 25x25 km in order to yield more meaningful results for urban agglomerations. Pollutants addressed are O3, NO2 and PM.
Data are currently provided and published at airqualitynow.eu for the pilot cities of Rome, Prague, Rotterdam and Maribor, taking into account measured and modelled air pollution data, local or regional emission dispersion models, weather forecasting and forecasted traffic flows when applicable. CITEAIR also provided Guidelines for Air Quality Forecasting, which any city is free to use.
City-level air quality forecasting has the potential to be a very useful tool, but only if accurate and high-quality data are provided and if the model used corresponds to specific circumstances and framework conditions of each city involved. Corresponding investments in measuring and modelling might pay off quickly in reduced exposure to health risks, presuming, however, that investments in information on forecasted air quality are followed by measures to reduce pollution and change group behaviour. The other key factor, of course, is that city authorities must possess the political will to take real steps towards improving air quality. The tools developed by CITEARI I and CITEAIR II will hopefully generate a wave of citizen demand for the provision of air quality forecasting in more and more European cities. And, hopefully, Europe's mayors will be tuned in.
