Ian Lockwood

Screen grab of AQICN’s Colombo page (based on US Embassy data on Tuesday 27 November 2018)

The issue of air quality has been in the news lately with the destructive Camp Fire in northern California and resulting air pollution in the San Francisco Bay area. Poor air quality is nothing new, of course, and has been a fixture of the less desirable side of urban development and agricultural practices. In our Asian neighborhood, cities like New Delhi and Beijing, have regularly been in the news for their frightening air pollution. South East Asia has faced serious problems from the clearing and burning of tropical forest for agricultural expansion (see the articles below by Adam Voiland). Colombo Sri Lanka, where I am based, has much less of a problem but there are development plans and changes that could contribute to an increase in poor air quality. The OSC IB Environmental Systems class is currently completing their internal assessment on air quality in topic 6 (Atmospheric Systems & Societies). This post considers and shares resources for monitoring air quality at a variety of scales that I have been exploring with the students. The goal is to document resources to understanding air quality measurements and work to reduce causes with interested readers, students and teachers.

MEASURING AQI

Many countries have been monitoring and reporting on air quality for some time.The Air Quality Index (AQI) is a measure used to measure and monitor the quality of air. However, there is not necessarily a common standard scale, even though most are called “AQI” (see Wikipedia’s page for a summary of the different AQIs). For example, India’s AQI is on a scale of 0-500 with eight different components measured (NAQI). The UK is on a scale of 0-10 with five major pollutants (UK AIR). China’s AQI measures six pollutants on a scale of 0-300. Thus, it has been difficult to compare values on a global scale.

For the purposes of our student work we have used the AQI established by the Environment Protection Agency (EPA) in the United States. It is based on measures of the following five pollutants.

• ground-level ozone (O₃)
• particle pollution (particulate matter) (PM₂ or PM₁₀)
• carbon monoxide (CO)
• sulfur dioxide (SO₂)
• nitrogen dioxide (NO₂)

Each of the pollution segments has a standard, set by the EPA. This is used to evaluate the quality of the air based on the measurement. The scale of the AQI runs from 0-500 but, in reality many cities are off these charts and getting close to 1,000! For example, today (November 27^th at 2:00 pm) Delhi has an AQI of 492 and several places in China in the Beijing area have an AQI of 999!

Screen grabs from India’s National AQI data portal (Chennai on 29 November 2018).

Screen grabs from India’s National AQI data portal (New Delhi on 29 November 2018).

US EMBASSY DATA

There are now  online tools to help students, teachers and other interested citizens become more aware of the spatial extent of the problem using a single AQI measure. The US State Department is recording and sharing AQI data at their global network of embassies and consulates. AirNow (of the EPA) has a website where the current data from these embassies and consulates is layered on an OpenStreetMap. If you click on this link you can input a city with a US embassy/consulate and then access both current and historical data. Many places have yearly data, collected every hour going back to 2015! This is an ideal resource for science teachers looking to find meaningful secondary data for students to use in analysis.

Screen grab of Colombo data showing hourly progression (15 November 2018).

Screen grab from AIR NOW’s US Embassy portal showing AQI in Dhaka Bangladesh (29 November 2018).

Portal to the World Air Quality Index site.

You can also look up global data sets at the World Air Quality Index project’s site at www.aqicn.org . This site, based in China, compiles AQI data from around the world and maps it. Thus far, I have not been able to download historical data from the site. They do have several useful links including an Asian forecast page.

Unfortunately, we live in a world where many people are exposed to dangerously high levels of air pollution, as the links above share. It is hoped that the data and the knowledge of these patterns will help our communities look for meaningful changes in our daily lives such that we reduce and eliminate the cause of human induced air pollution.

Special thanks to students Camille-anh Goulet and Jordan Wright and OSC parent Michael Cragun for sharing links and ideas that have contributed to our understanding of AQI.

REFERENCES

Al Mukhtar, Sarah et al. “Hell on Earth” New York Times. 18 November 2018. Web.

Camp Fire Spreads Foul Air in California. NASA Earth Observatory. 11 November 2018. Web.

India National Air Quality Index Portal. Web.

US Environmental Protection Agency. Air Now. Data Portal. Web.

US Environmental Protection Agency. Air Now: US Embassies & Consulates. Data Portal. Web.

Voiland, Adam. “It’s Fire Season in South East Asia.” NASA Earth Observatory. 1 March 2018. Web.

Voiland, Adam. “Smoke Blankets Indonesia. NASA Earth Observatory. 27 September 2015. Web.

World Air Pollution: Real Time Air Quality Index Portal. Web.