What a year it was, right? And it still feels like there are ages for this year to come to an end. The whole world went through tragic times indeed. But when it comes to the wellbeing of the world itself, some data indicates vice versa.
Did staying home more mean less pollution for this year? Well, it seems like it. NASA's GEOS atmospheric composition model has served the figures based on world models with and without COVID-19 and it seems that all our Earth needed was fewer humans.
The comparison results were presented at the 2020 International Conference for High Performance Computing, Networking, Storage, and Analysis.
Since February, global nitrogen dioxide concentrations have reduced approximately 20%, compared to the computer model of the world without COVID-19.
“In some ways, I was surprised by how much it dropped,” explained lead author, Christoph Keller from Universities Space Research Association (USRA) at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “Many countries have already done a very good job in lowering their nitrogen dioxide concentrations over the last decades due to clean air regulations, but what our results clearly show is that there is still a significant human behavior-driven contribution.”
In total observations of 46 countries, 50 of the 61 analyzed cities show a reduction range between 20-50%.
“You could, at times, even see the decrease in nitrogen dioxide before the official policies went into place,” said co-author Emma Knowland with USRA at Goddard’s GMAO. “People were probably reducing their transit because the talk of the COVID-19 threat was already happening before we were actually told to shut down.”
The model was based on a "normal" 2020, not very different compared to other years. People were allowed to behave the same as before, going outside, using transportation in large numbers, and no shutdowns taken into consideration. The results have shown that the same number of pollutants would be added to the air.
Then, that model and this year's real observations made by satellites during shutdowns rolled out the results.
First ensuing in Wuhan, China, the shutdowns across the countries and cities have in fact contributed to keeping the air less polluted. About 60 percent of emissions seemed to have diverged from what models predicted.
NASA unveiled various cities' data, for example, a 60% decrease was shown in Milan and Madrid, while New York followed with a 45% reduction.
Well, the Earth finally seems to have taken a deep breath.