Pollution Stepping Back on Earth Day


Earth Day was yesterday and, for the first time in the 50-year history of Earth Day, the skies look cleaner than the year before. While the COVID-19 shutdown has negatively impacted lives around the planet, it is also impacting the planet itself, in a positive way.
“Right now we’re seeing reduced levels of the pollutants that we see at NASA that we can measure from space,” said Dr. Ana Prados, program manager of NASA Applied Remote Sensing Training (ARSET) at NASA Goddard Space Flight Center. “We’ve seen a reduction in nitrogen dioxide and also a relaxing in the particulate pollution, the fine particles that can cause breathing difficulties and other health issues. So what we’re seeing is something that’s consistent with people driving less; just less economic activity overall is what’s leading to the improvements in air quality that we’re seeing.”
The shutdown resulting from COVID-19 has a sizable chunk of the world’s population staying “safer at home” and either telecommuting to work or having their business closed outright, with only essential services workers still commuting into their jobs each day. This sizable chunk is the ones off the roads, not using their cars to pollute the air. Combine this with a reduced number of operating companies and a reduced number of laborers shipping a reduced selection of goods, and there is less traffic and pollution from commerce. Due to public activity spaces being closed there is no pollution output from places like theme parks, motor sports, boating or unnecessary travel for conferences, sporting events or vacations. All of these combine to give the near-Earth atmosphere a bit of a break from the constant output of particulates, nitrogen dioxide and Volatile Organic Compounds, which create ground air pollution.
Ground air pollution, which is in the near-Earth air we breathe, is clearing a bit during the shutdown; however, this break isn’t going to make a dent in the climate change pollution – the greenhouse gases – that have already been released.
“The greenhouse gases are a different kind of pollutant, for the most part, than the ones we think about impacting people’s ability to breathe or causing cardiovascular disease,” Dr. Prados said. “That’s going to be mostly your carbon dioxide and your methane; chlorofluorocarbons are important as well – they trap a certain amount of energy and, if there’s more of those gases, then that energy is not escaping back into space. So it does lead to a warming [of the Earth] and those have a lot of the same sources … but how they impact us as humans is very different. The air quality improvements we’re seeing with the COVID-19 [shutdown] are a very immediate thing.”
He added that if everyone in Los Angeles who drives daily to work stopped, an immediate change would be seen in air quality.
“Tomorrow we would see it,” Dr. Prados said. “However, the greenhouse gases are a much longer term process because they stick around for, in some cases, thousands of years. So if we all stop driving tomorrow, everybody on the planet, you wouldn’t see the kind of change [in greenhouse gases] that you would see with the other pollutants because we still have a lot of CO2 in the atmosphere that’s going to take hundreds of years to get rid of.”