And like everything else, that means something slightly different during a pandemic, climatologists are calling The massive drop off in emissions in society slowed down.

One big experiment a chance to see a world without us humans playing such a prominent part.

The question.

What lessons can we learn?

Our Clayton Sandell reports the 50th anniversary of Earth Day lands in the middle of a global pandemic, giving humans a glimpse of what the planet might look like if we took better care of it.

Take care quality With fewer people on the roads, skies over New Delhi this week turned from hazy brown to a rare blue.

In Paris, where satellite pictures show empty streets around the Arctic Triomphe, air pollution is down 46% 19% in Sydney, 29% in L.

A.

In San Francisco, where more people are walking and riding bikes, the city is shutting down 13 miles worth of streets, giving more room to social distance.

I think it's good cause then I could ride my bike all over the streets.

Airlines air suffering from empty planes and airports.

But climate scientists say lower emissions thanks to a 70% drop in global flights might have an upside.

One passenger one way from New York L.

A.

Has the equivalent of melting 30 square feet of sea ice, thanks to Corona virus shutdowns that have devastated the economy, Environmental changes are now happening at an unprecedented rate.

We're all part of a big experiment here.

I don't think we've ever seen such an abrupt and simultaneous drop in our emissions.

These are crazy times, but for for the Earth is it's maybe a breath of fresh air for animals like this kangaroo in Australia, it's a time to reclaim near empty city streets.

There was the goat jam in the UK lions sunning themselves on a South Africa road.

Big cats jumping walls in Chile, bores in Israel and coyotes in San Francisco, Yosemite National Park had four million visitors last year.

Today, zero What are the animals doing since the park has been closed?

For the most part, I think they're having a party like I think that this time of year is difficult for the animals.

Here.

There can be literally walls of cars or people in the park.

There are things scientists say the pandemic likely won't change Like global warming level of carbon dioxide humans, air pumping into the atmosphere may be slowing, but overall, it's still rising.

We've been altering our atmosphere in significant ways since the dawn of the Industrial Revolution.

Things started going up in the early 18 hundreds, so six months changing emissions is not gonna have a huge effect.

Environmental advocates say the shutdown hasn't slowed Trump administration rollbacks in the past few weeks, delaying Obama era vehicle mileage standards and rolling back coal power plant emission standards.

As quarantines end and Americans shift out of park in the coming months, plummeting gas prices may give them motivation to drive even more than before.

In the long term, we end up with MAWR air pollution and in fact, mawr fossil fuel emissions, because there is this desire to sort of get back to business as usual.

So in the long term, is this going to save lives or harm lives?

I think it remains to be seen.

But what's happening now, scientists say, provides a glimpse into a sort of parallel universe where the possibilities of alternative energy, lower emissions and less pollution can be seen.

right now, if only for a short time.

Three Time to take stock of how our daily impact, our our daily lives are action truly do impact environment.

We're all in this together way all share the same nest.

And I think that's one thing is pandemic may be showing us is that our actions do affect one another.

E like that.

We all share the same nest.

Hi, everyone.

George Stephanopoulos here.

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