Children are on the front lines of America’s air pollution problem, according to the American Lung Association's newest State of the Air report.

At first glance, the headline is hard to ignore: Almost half of all kids in the U.S. (46%) live in areas with failing air quality grades, and more than 7 million are currently exposed to unhealthy levels across all major pollution measures.

This is especially concerning because children's lungs are still developing and they tend to spend more time outside, meaning polluted air can have a bigger, longer-lasting impact on their health.

When you zoom out to look at the adult population, the picture doesn't improve. This year's report found that 44% of Americans overall (about 152.3 million people) are still breathing unhealthy air.

More than 61 million people live in counties with failing grades for short-term particle pollution, 76 million people live with unhealthy year-round pollution, and about 4 million more people are now affected by ozone pollution than in recent years.

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The Good And The Bad

Certain cities continue to struggle year after year.

• Bakersfield, California, remains the worst in the nation for year-round particle pollution for the seventh straight year
• Fairbanks, Alaska, now ranks worst for short-term particle pollution spikes
• Los Angeles continues to lead the nation in ozone pollution
• Other metro areas consistently ranking among the most polluted include Fresno, Visalia and San Diego, California; Brownsville, Texas; and Eugene, Oregon

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Only one metro area earned top marks across ozone, short-term particle pollution and low year-round particle levels: Bangor, Maine. That’s down from multiple cities in previous years, showing just how challenging it’s becoming to maintain consistently clean air.

A Mixed Bag

Unfortunately, there’s no simple “getting better” or “getting worse” story in this year's report. Just like Meryl Streep and Alec Baldwin, it's complicated.

Particle pollution did show some improvement, breaking a decade-long trend of worsening conditions. But trends show far more people are being exposed to it than in the past, especially during short-term spikes.

Here’s where things get even more complex. Experts found that the gains made under policies like the Clean Air Act are now being challenged by a changing climate.

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Extreme heat, drought and especially wildfires are fueling more high ozone days and spikes in particle pollution.

In other words, even as we cut emissions, climate-driven events are adding pollution back into the air, making it harder to protect public health.

It's not all doom and gloom. Experts say cleaner air is possible, and the U.S. has proven that over decades.

The newest report highlights how that progress now requires more attention and coordination, especially to protect America's youngest and most vulnerable.

weather.com lead editor Jenn Jordan explores how weather and climate weave through our daily lives, shape our routines and leave lasting impacts on our communities.