It had to happen. We finally saw an image of a black hole---a heretofore invisible object 500 light years from the earth---and yet, just a few weeks before, we had trouble seeing Denver’s skyline from only miles away! Indeed, Denver and the metro area’s air quality on four days over the last six weeks was just that filthy and failed to meet government clean air standards.
What hung in the air over Denver the first week of March and a single day so far in April was a combination of carbon monoxide, industrial smoke, dust and oil and gas particulates. All mixed together, they made for a visual stew of aesthetic gunk visible for miles. Of course, for those walking in this cauldron of toxicity, it was pretty much invisible. Breathing it in, however, was a whole other matter.
The brown cloud affecting the most populous parts of Colorado---essentially front range cities from Fort Collins to the north stretching to Colorado Springs on the south---is caused by cold surface air being trapped under a layer of warmer air. Until the temperatures rise, the poor quality---ozone or particulate matter---air remains static. It also remains dangerous.
“Ozone is irritating to the lungs,” said Janice Nolen of the American Lung Association. “It’s kind of like getting a sunburn on your lungs.” Particulate matter, things like ash, soot or fossil fuel particles are microscopic, hundreds of times as fine as a human hair, said Nolen. “They can lodge in your lungs or sometimes go directly into the bloodstream.” They can trigger asthma attacks and complicate breathing. They can also shorten life. The elderly and very young are at higher risk of health complications.
The geography of Denver, sitting next to a mountain range and at a mile high in elevation, contributes to the periodic inversion that occurs. It aids in trapping cold surface air under layers of warmer air.
The metro area’s recent bout of poor air quality was thought to be history and addressed during the 70’s when the brown cloud became a legislative imperative. Clean air standards in the 70’s were far inferior to what they are today. But weather patterns---a major factor in inversions---have not changed. What has changed is a spike in population. In 1970 the metro area’s population sat at just over a million. Today nearly three million call the metro area home.
But with winter waning and warmer weather on the way, said Dr. Richard Wagner, Professor of Meteorology at Metropolitan State University of Denver, the region will still be impacted by inversions and complications caused by climate change.
“The hotter and sunnier the days, the ozone levels tend to be worse,” said Wagner. “To the extent that we’re having more hot days in summer one would expect to have more bad air quality days in summer.”
Over the last several years, record high temperatures have occurred with greater frequency than anytime in recent memory. An overwhelming number of scientists attribute this new pattern to climate change along with human activities. It’s not just one thing or one record warm day, said Wagner. “When we look at climate change, we’re looking at monthly data, long-term averages,” he said. “We’re looking at lots of observational data.” These data include droughts and frequency of droughts.
One manifestation of this trend can be seen with a quick trip to the mountains in Colorado or any number of western states where pine beetle infestations have ravaged forests. Vistas that normally would have been painted a lush, verdant shade of green are now awash in trees tinted tan to rust.
Winter time temperatures have not fallen either far enough or long enough to reduce the beetle population. As a result, the forest is not simply a seasonal source of food but a year-long source. Since 1994, the pine beetle is said to have impacted nearly 3.5 million acres of Colorado forests.
Across the West and as far north as Alaska, the beetles’ deforestation is measured at an astronomical 60 million acres. It’s an area larger in size than the state of Missouri. But scientists say it’s not just a loss of forest that is at stake. It affects entire ecosystems including animal populations, timber-mill economies, increases the chances of wildfires and soil erosion. It is a beetle tsunami that scientists, so far, have not found a defense for.
Scientists say eleven of the twelve warmest years since 1850 have occurred between 1996 and 2006. The rise in temperatures has contributed to everything from melting glaciers to rising sea levels. Already in a number of American cities, including Miami and New Orleans, seawater that had previously not been a concern could now conceivably make it farther inland causing erosion, upsetting wetlands, compromising aquifers and upsetting a natural balance for fish, bird and plant habitat.
The arguments over climate change will surely continue. But they won’t stop the changes science marks daily or reverse the damage they believe has already begun to occur.