Professor Lewis Dartnell, Professor of Science Communication, wrote an article for the BBC Sky at Night magazine about whether COVID-19 restrictions have affected light pollution.
In the article, Professor Dartnell wrote about how a clear drop in air pollution levels has led astronomers to see if restrictions have reduced light pollution levels too. They collected data for the city of Granada in Spain both before the pandemic and during the lockdown from mid-March to the end of May 2020.
He wrote: “The main source of information on global night-time light emissions is the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard the Suomi NPP satellite. But the problem with using this dataset to compare light pollution before and during the pandemic is that the images are taken by the satellite passing overhead at 1:30am local time, long after most people have already gone to sleep and lights are turned off.
“As Maximo Bustamante-Calabria at the Astrophysical Institute of Andalucia explains, the key to uncovering the effects of human activity is in combining this satellite imagery with local ground measurements of sky brightness.”
Talking about how they gathered the results, Professor Dartnell said: “Bustamante-Calabria and his team had to first disentangle the relationship between the lower levels of particle pollution in the air scattering light, and any decrease in the amount of artificial lighting during the pandemic. When they allowed for these variations, the data revealed that during lockdown the overall light output of the city had decreased by around 20 per cent.”
Read the full article on the Sky at Night Magazine website.
