It's that time of year again: The thermostat has risen, you sweat standing still ... in the shade, and the air is dense with water, ozone and who knows what else.

And, you know what that means: We've got ourselves a week full of air quality alerts. This week's color is orange.

You can keep up with air quality alerts in several ways. First, and maybe easiest, is to sign up for the air quality alert e-mails from the state's Division of Air Quality through a website called EnviroFlash. Here's the link. As far as I can tell (I've been on this e-mail list for a couple years now), the organization doesn't sell or share e-mail addresses.

The site also offers helpful tips on how you can help reduce air pollution:

Care for the Air

--- Drive less: carpool, vanpool, take the bus, telecommute.

--- Conserve electricity.

--- Pack a lunch or walk to lunch.

--- Avoid idling your vehicle.

--- Refuel and mow after 6:00pm.

And, it explains what the color codes mean:

Air Quality Index (AQI)

Green...........0- 50 AQI........Good air quality. No health risks are expected. Enjoy outdoor activities!

Yellow.......51-100 AQI........Moderate air quality. Air quality is okay, but unusually sensitive people may be affected, especially when the AQI nears 100.

Orange....101-150 AQI........Air quality is Unhealthy For Sensitive Groups. Children, active adults, and those with heart or respiratory disease, including asthma, should limit outdoor activity.

Red..........151-200 AQI........Unhealthy air quality. Everyone should avoid prolonged outdoor activity.

Purple......201-300 AQI........Very Unhealthy air quality. Everyone should avoid outdoor activity.

You can also keep up with alerts on the state's Division of Air Quality website, though it's a little less intuitive. Here's the link.

And, there's always Twitter. This account, @CharlotteAQF, is, well, focused on Charlotte's air quality. If you're not from 'round these parts, simply go to search.Twitter.com and search for your city plus "air quality" and see what pops up. You do not have to be a Twitter user to see the @CharlotteAQF Tweets.

You might also want to find out if these air quality alerts -- this week we've got orange alerts for ozone and yellow for particle pollution -- will bug your lungs. You can do that by reading up on what ozone and particle pollution is, why it's important to monitor and how it can reach alert status.

Here are a few links that you may find helpful to that end from the U.S. Environmental Protection Agency:

What is Air Pollution?

What is Ozone?

What is Particle Pollution?

And, AirNow.gov, which also offers color coded alert information.

Also, the U.S. Centers for Disease Control and Prevention has some links about how air pollution affects your health. Most of them can be found from their "Air Pollution and Respiratory Health" landing page, which is here.