Part 3: Track air quality over a longer period. Procedure 1. Find historical data of air quality by state. a. Go to the AIRNow https://www.airnow.gov/state/alabama b. Choose your state from the dropdown menu. Click on the Historical Air Quality. A table showing the cities within your state, for a given date. c. Choose a day, such as the first of the month, and click on the square of the calendar representing that day. Find the Daily Air Quality Index (AQI) for a nearby city. 2. Record your data. a. Make a list on which you will record air-quality levels for two days in each month for the past six months. You will record the level for two days each month. They should be days that are widely separated, such as the 1st and the 15th. b. Use the following format, plugging in your own data: October 15, 2009-good November 1, 2009-moderate November 15, 2009-good c. After you record the air-quality level from the first table, click Pick Another Date at the top of the page. d. If the next day you want to record is your second day for that month, click on the square of the calendar representing that day. e. If you need to advance to a different month, click the back arrow in the calendar to go to the desired month (and year if necessary). f. Repeat this procedure for two days in each month for the past six months. 3. Graph your data. a. Create a line graph. On the x-axis place tick marks for the months and days whose air quality you have

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