PHOENIX (3TV/CBS 5) -- Traffic on valley roads is always at high volume, thanks to the millions of people who call the Phoenix-metro home. But with the stay at home order, fewer of us are driving to work, school, or other activities.
"Our ozone is lower, that is what we expected with less traffic and emissions out of vehicles," said Matt Pace, Meteorologist for Arizona Department of Environmental Quality.
ADEQ is analyzing the information their EPA models are collecting and have seen a 37 percent drop in nitrogen oxides between March 16-22nd of this year compared to last year. The pattern is following that of when the recession hit the Valley just a few years ago.
"2008 and 2009, we did see a big drop in ozone levels, and we could see it again if less traffic is on the road," said Pace. ADEQ is also looking at emissions testing. "We are trying to test out two parts. Which one is the decrease in emissions of less traffic, or is it because of weather being more active."
This past March was very active with storms; in fact, it was the 10th wettest on record. Our weather patterns throughout the year affect our air quality in our summer heat.
"Sunlight and heat interact with emissions and creates an ozone layer near the surface," said Nancy Selover, State Climatologist for Arizona. And when it comes to our winters. "We have a lot of inversions layers where cold air gets trapped at the surface, so all of those tailpipes emissions get kind of stuck," said Selover.
This is what creates that brown cloud over the Valley. April is the time of year we start to see our unhealthy air quality ramp up.
"We are expecting as we head into April with weather active and people staying home that we should see lower ozone a bit," said Pace.
But ADEQ cautions that an immediate cleanup of our air isn't going to happen overnight, it will take time for the environment to catch up. They will rerun their models in three weeks and compare them to see if the decrease continues.