Mapping Smog

Summer is the season for warm weather and enjoying good times in the great outdoors. But, it also has a few downsides. Mosquitoes, for one, abound at this time of year. Another is smog and its impact on air quality.

As part of the effort to help people understand the problem of smog and deal with its effects, Canada and the United States have developed real-time maps to track the movement of ground-level ozone.

The term "smog" originally referred to a mixture of smoke and fog in the air. Today, smog describes a noxious mixture of air pollutants including gases and fine particles. The two key components of smog are airborne particles and ground-level ozone.

Airborne Particles

Airborne particles are either solid or liquid particles that are small enough to remain suspended in the air. Particles give smog its colour, which range from brown, to dark grey or white, depending on the type of particles. There are two categories of particles, defined by their size.

The larger particulate size, defined as PM₁₀, measures less than 10 microns across and is composed primarily of soil, soot and dust from construction and agriculture.

The smaller sized particles, known as PM_2.5, measure less than 2.5 microns across. These finer substances are released directly to the atmosphere primarily from industrial smokestacks and automobile tailpipes, but a large percentage is actually formed in the atmosphere from other pollutants such as sulphur dioxide, nitrogen oxides and volatile organic compounds.

The very fine PM_2.5 particles cause the greatest concern for human health. They penetrate deep into the lungs, where they cause irritation and can exacerbate lung disease. They are also responsible for reduced visibility.

Ground-Level Ozone

Ground-level ozone is one of the main atmospheric pollutants contributing to smog. This highly irritating pollutant forms when solar radiation "cooks" the soup of chemicals floating in the atmosphere above urban areas on hot summer days. Unlike the stratospheric ozone that protects us from ultraviolet radiation, ground-level ozone is harmful to our health and can cause serious respiratory difficulties. Health experts recommend that seniors, children and persons with respiratory problems remain indoors when ground-level ozone levels are high.

Ground-Level Ozone Mapping

Ground-level ozone concentrations vary from region to region across Canada. Internet users can now view maps showing the concentrations of ground-level ozone in Eastern Canada and the United States.

The Canadian portion of the AIRNow Web site provides maps showing real-time information on ozone concentrations in Ontario, Quebec, New Brunswick, Prince Edward Island, Nova Scotia and Newfoundland. Maps included on the site for the United States cover the entire country. Maps for the United States cover most of the country, with a primary focus on the mid-Atlantic to New-England states.

The Canadian ozone map site is a collaboration between six Eastern Canada provinces and the Eastern U.S. states, mostly from New England. Additional partners for the project include Environment Canada and the U.S. Environmental Protection Agency (EPA). The information found in the maps will most likely be of particular interest to dwellers of the Eastern Canada and the United States, where ground-level ozone concentrations are especially high.

What Are The Implications For Canadians

If your region is represented, take a look at the smog levels on the AIRNow ozone mapping Web site in order to help plan your outdoor activities, or visit the Air Quality Services site for additional information on air quality forecasts available for certain regions of Canada.

If the map indicates that ozone levels are high, try to avoid vigorous activities outdoors. Keep in mind that individual sensitivity to smog can vary. Those with heart and lung disease, including asthma, may be affected by smog at standards well below the levels at which advisories are issued. Exposure to ground-level ozone can be reduced by staying indoors, particularly in buildings with air conditioning.

Many of the choices we make each day have a direct impact on the amount of pollution which goes into our air. Doing your part to reduce energy use and making wise consumer decisions, will go a long way to improving air quality.

What You Can Do

How can individuals make a difference and help with the improvement of air quality in their region? The answer is easier than most think.

• A change in your everyday transportation, such as taking the bus instead of using your car or turning off your vehicle instead of idling your engine, can significantly reduce the amount of air pollution.
  
  
• Switching to electric or human-powered machinery instead of using gasoline-powered tools and vehicles helps in the improvement of our air.
  
  
• Say no to solvents: some household cleaners (e.g., mineral spirits) and surface coatings (e.g., oil-based paints) may contain smog producing elements.
  
  
• Avoid open burning of refuse or garden waste.

A change in our basic daily routines can make a difference and help toward achieving cleaner air in our communities.