If in case you have been listening to about poor air high quality in New York Metropolis Friday, you’ll be able to breathe a deep sigh of reduction (actually): our air high quality is okay. Typical air high quality within the metropolis falls beneath 50 on the air high quality index (AQI), throughout the “good” vary.
The previous few days have seen air high quality tick over into the 60s, edging us into the “moderate” class on the AQI. However simply barely. Inside this vary, air high quality is nowhere close to a stage that might start to trigger any misery to folks strolling or exercising outdoors, even when you belong to a extra delicate group.
Our barely larger quantity on the AQI is a results of marginally larger concentrations of particulate matter (PM 2.5) within the air. You’ll typically see us speaking about PM 2.5 when wildfire smoke is filtering into our area; fortunately that isn’t the case this time round.
As a substitute, these particulates are coming from normal metropolis exercise: automobile exhaust, industrial emissions, something involving the burning of fossil fuels.
So if that is simply normal metropolis air pollution, why is the AQI larger than it normally is?
We even have our quiet climate to thank. Excessive strain has been dominating over our area a lot of the week. This has stored our climate dry and sunny, but it surely additionally means our air hasn’t been transferring a lot. When you typically affiliate excessive strain with “good” climate, that “good” climate comes because of sinking air. However this sinking air acts like a lid over the air on the floor holding it, and the pollution inside it, in place.
Merely put: excessive strain makes it tougher for polluted air to rise and disperse, turning air on the floor stale, particularly the longer excessive strain stays round. An excessive instance of that is the Nice Smog of London in 1952, however we’re nowhere close to something like that.
You’re free to go about your day unencumbered by the air high quality; it’s not a distinction even perceptible to most individuals. However if you wish to look to the horizon, you’ll be able to catch a glimpse of the layer of stale air trapped on the floor, as seen within the shot beneath from Earth Cam’s Statue of Liberty digital camera.
