1
00:00:00,000 --> 00:00:07,100
When the world went into lockdown to slow the spread of COVID-19, emission of pollutants into the atmosphere plummeted.  

2
00:00:09,166 --> 00:00:12,566
A team of international researchers led by scientists at NASA’s Jet Propulsion Laboratory charted the drop in emissions 

3
00:00:12,566 --> 00:00:15,966
and how it impacted global air pollution and the climate system.

4
00:00:18,100 --> 00:00:21,600
The study found that levels of nitrogen oxides (NOx), which react  to form surface-level ozone, globally decreased by 15%.  

5
00:00:21,600 --> 00:00:27,033
This drop in NOx resulted in a 2% global drop of ozone near Earth's surface.

6
00:00:27,700 --> 00:00:30,700
Ozone high in the upper atmosphere protects us from destructive solar radiation. 

7
00:00:30,700 --> 00:00:33,700
But when it's closer to the ground, ozone is harmful to human health. 

8
00:00:34,533 --> 00:00:38,100
While a 2% drop may seem small, this drop in ozone, which occurred over 8 months, 

9
00:00:38,100 --> 00:00:42,233
would take 15 years to achieve under even aggressive emission control scenarios. 

10
00:00:42,233 --> 00:00:47,566
Ozone depends on a number of factors and not just NOx emissions alone,

11
00:00:47,566 --> 00:00:51,600
which is why the team pulled together a variety of air quality measurements 

12
00:00:51,600 --> 00:00:55,633
and combined them with a computer model to understand what happened.

13
00:00:55,633 --> 00:01:03,766
This map, created using measurements of atmospheric gases from NASA and European Space Agency Earth-observing satellites,

14
00:01:03,766 --> 00:01:10,400
shows where ozone reductions occurred worldwide.

15
00:01:22,000 --> 00:01:37,333
The results of the study imply that both NOx emissions and ozone near Earth's surface will climb again as the global economy opens up. 

16
00:01:37,900 --> 00:01:43,200
However, the study provides a unique glimpse into a future with better global air quality. This future could be achieved with 

17
00:01:43,200 --> 00:01:48,166
sustainable measures that could improve both human health and climate.