Satellite image of particulate pollution over Beijing, China.
Click on image for full size
NASA image courtesy the MODIS Rapid Response Team

Aerosols and Climate Change

There are little particles in the atmosphere that are so small and light they can float in air. These particles are called aerosols. They may be small but they have the ability to change climate.

Some aerosols are a natural part of the atmosphere - coming from erupting volcanoes, sea salt, and wildfires. However, burning of fossil fuels like coal, oil, and gas has let lots more aerosols loose in the air. Aerosols are a part of air pollution. They are dangerous to human health and they also dampen the effect of global warming.

Aerosols in the atmosphere can change the amount of solar energy that is reflected away from Earth. Different types of aerosols react differently when hit with sunlight. Sea salt particles reflect sunlight back out into space. Black carbon particles from burning of wood or fossil fuels absorb most of the sunlight that hits them.

Aerosols help clouds form and clouds have an impact on climate. The millions of little droplets of water that make up a cloud each need a little particle, like an aerosol, to condense upon. More aerosols can create more clouds. Different types of clouds may have different impacts on climate and this is a topic that scientists are still exploring. But in general, clouds reflect incoming solar radiation back out to space.

Scientists think that over most of the last century the overall effect of the added aerosols was a reduced amount of global warming. Today, however, as new technologies have allowed factories, power plants, and automobiles to release less air pollution into the atmosphere, the amount of aerosols has dropped. That's a good thing since air pollution is a problem for human health. But it has also means that the pace of global warming is likely to increase.

Last modified May 13, 2011 by Jennifer Bergman.

You might also be interested in:

Cool It! Game

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Aerosols: Tiny Particulates in the Air

When you look up at the sky, you are looking at more than just air. There are also billions of tiny bits of solid and liquid floating in the atmosphere. Those tiny floating particles are called aerosols...more

What Is Climate?

The climate where you live is called regional climate. It is the average weather in a place over more than thirty years. To describe the regional climate of a place, people often tell what the temperatures...more

Black Carbon

The burning of fossil fuels like coal, gas and oil releases particles into the atmosphere.  When fossil fuels are not burned completely, they produce black carbon -- otherwise known as soot.  Soot looks...more

Air Pollution

What do smog, acid rain, carbon monoxide, fossil fuel exhausts, and tropospheric ozone have in common? They are all examples of air pollution. Air pollution is not new. As far back as the 13 th century,...more


This picture of the Earth surface was taken from high above the planet in the International Space Station. In this view from above, we can see that there are lots of different things that cover the Earth....more

How Clouds Form

A cloud is composed of tiny water droplets or ice crystals that are suspended in the air. A series of processes have to happen in order for these water droplets or ice crystals to form into clouds in the...more

Effects of Climate Change Today

Over 100 years ago, people worldwide began burning more coal and oil for homes, factories, and transportation. Burning these fossil fuels releases carbon dioxide and other greenhouse gases into the atmosphere....more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA