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Scientific American 60 Second Science. I'm Emily Schwang.

This is the sound of a neighborhood in Calcutta, India in December 2016.

It was recorded by resident Succantama Jumdar. And this is what that same neighborhood sounded like on April 1st of this year after the COVID-19 lockdown.

It's like a unique place and time that we have to document for the future for sure.

Amundingask is a soundscape ecologist with the French National Research Institute for Sustainable Development.

She's supposed to be in the field, recording nocturnal sounds in southern France,

to evaluate the effect of light pollution on animals there.

Instead, she's at home, but she's still recording.

Now from her balcony, where normally she'd mostly be hearing traffic.

In my neighborhood, there's like amphibians, like I think it's frogs that are like in this

very located space in the neighborhood that's very loud. So at night there's like the frog chorus and the morning you have the bird

choruses and you also hear like sounds of people in the gardens slight music music in the back, it's very relaxing.

When the pandemic hit, Gask and three other colleagues put a call out to volunteers all over the globe.

Currently, roughly 300 people are recording one minute of

outdoor sound every 10 minutes for what's become the silent cities project.

The goal is to build this huge data set and make it available.

All the data collected will be stored by the Open Science Foundation as a public data set.

The recordings, says Gask, offer opportunities in the future to understand how we

share our space with other creatures and how we impact our outdoor spaces.

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