When packing for your travels, it doesn’t hurt to check the air quality forecast!

Yes, air quality forecasting is now a thing.  You may have thought that the weatherman on TV had an easy job, but air quality is adding a new dimension to forecasts, and it’s complex.  Air quality forecasting science predicts how meteorological variables such as temperature, humidity, and wind speed will influence the behavior and concentration of air pollutants. This is combined with environmental monitoring of common pollutant sources, like pollen and vehicular traffic, to gain a more complete evaluation of current and future air quality.  (The Science Behind Air Quality Forecasting: Computational Models and Weather Data Sources)

Currently in the world, there are a lot of air pollution events going on, such as:

• Canadian wildfires, smoke from which is drifting south and into the US midwest and east coast

• The Hayli Gubbi volcano in Ethiopia is erupting for the first time in 12,000 years, sending an ash plume into the atmosphere

• Kīlauea volcano on Hawaii is still erupting periodically

• India’s Delhi is having record-breaking air pollution

Obviously the first three above contain unforeseen events, such as wildfires and volcanoes, but once they occur, weather patterns can help project air quality in the coming weeks.  The fourth is an example of seasonal probability (Delhi’s air quality worsens every winter due to temperature inversions, mountain ranges, and fireworks during the Diwali holidays).  Therefore, it’s possible in most cases to make local air quality forecasts at least a few days out.  Travelers and local residents alike need to plan their outings, because sometimes the air is too dangerous to ignore, especially for children, the elderly and those affected by respiratory conditions.

Air quality forecasting depends heavily on accurate weather forecasting.  The following aspects of weather affect the air quality: (The Science Behind Air Quality Forecasting: Computational Models and Weather Data Sources)

• Movement of “fronts” of weather: Incoming fronts can disrupt “inversion” climates that trap pollutants in valleys

• Wind direction and speed: Strong winds will disperse pollutants from the local area and improve air quality, while the direction determines where they are carried next.

• Heat: On hot days, the climate has more energy, which leads to increased chemical reactions. For example, nitrogen oxides and volatile organic compounds (VOCs) react to become ground-level ozone, a key element of smog.

• Humidity: Water vapor in the air traps fine particles, allowing them to remain suspended in the air and contributing to higher contaminant levels.

• Precipitation: Rain and snow are generally good for air quality as they wash contaminants out of the air, but rain may also initiate different chemical reactions that lead to acid rain.

Of course, computers are taking the lead in generating these forecasts.  They use complex algorithms with inputs of contaminant concentrations and weather, then develop models that can be used to predict different outcomes (like the hurricane “spaghetti models” you may be familiar with).  Machine learning (AI) helps to make the forecast more quick and accurate.

Models require continuous weather inputs and refined knowledge of atmospheric chemistry, so researchers (humans) are also necessary.  Researchers and meteorologists are responsible for feeding the computers data sources including satellite imagery, weather Application Programming Interfaces (APIs), and data from personal weather stations and local monitoring stations. Radar can also help track storm systems.

This new field of air quality forecasting highlights the demand for computer knowledge, because we’re learning more and more that if pollution gets into the upper atmosphere (such as volcanic ash, wildfire smoke or even hydrocarbon releases), the resulting air pollution can affect weather worldwide, and computers enable faster forecasts.  For more information on wacky weather due to disasters, check out our article.  Here’s some takeaways: 

• If you or your children are interested in meteorology, consider the field of air quality forecasting, and don’t skip the computer classes!

• If you are traveling soon, and especially with children, elderly and sensitive people, don’t forget to check the projected air quality.

Photo by Larisa Birta on Unsplash