Air quality is important for
the environment and for human health.
We all breathe air.
Air pollution comes in the form of
fine particles and gases.
They cause acid rain and pollute rivers and lakes.
Breathing them puts people at risk
for asthma and worse.
Air pollution can be dust, haze, smoke,
and something called smog
because it looks like
a mixture of smoke and fog.
Some cities, famously Los Angeles,
have ground-level ozone that burns the lungs.
From space, earth lights up at night
where most people live.
Watch the lights change over the 20 years,
from 1992
to 2002
and 2012
More people, more cities, more lights, more energy
being used to power those lights.
Where does most of
the energy we use come from?
Burning fossil fuels.
In addition to producing energy,
burning fossil fuels produces air pollution.
Can you guess where most air pollution is found?
Satellites in space measure
chemical components of Earth's air pollution,
including nitrogen dioxide.
Nitrogen dioxide makes Los Angeles type smog.
Here is monthly NO2,
nitrogen dioxide, superimposed
over the lights at night.
Notice how most pollution is found
near the biggest cities and industrial areas.
Burning forests and fields also cause pollution.
In recent years air pollution in many places,
especially India and China
has reached epic levels.
There is however some good news too.
During the past 10 years
over the United States and Western Europe,
pollution has improved.
Emissions controls, more alternative energy,
switching power plants from coal to natural gas,
these all help.
A modern car in good repair produces
only about 5% of the pollution
that your grandfather's car
might have in 1960.
There's still more to do.
We can all improve air quality around the world.
We all share the earth, its atmosphere,
and everyone needs to breathe clean air.
For more information
visit climatebits.umb.edu