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Air pollution

earth science Maturity 9-11 climate
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Dirty things can get into our air.

Air pollution by industrial chimneys.jpg
Air pollution by industrial chimneys.jpg
This can happen outside. It can also happen inside our homes. Bad air can make people sick. We must work to keep it clean. Can you help us care for our air?

44 words

Dirty things can get into our air.

Air pollution by industrial chimneys.jpg
Air pollution by industrial chimneys.jpg
These can be tiny bits of dust. They can also be gases.

Sometimes this happens outside. Cars and big factories make dirty air.

BurningOffFieldsInTheEveningInSouthGeorgia.jpg
BurningOffFieldsInTheEveningInSouthGeorgia.jpg
Fires in the woods can do this too.

It can also happen inside. Many people burn wood to cook. This makes the air in homes dirty.

Dirty air can make people sick. It can also hurt plants and trees.

SMOG-DAMAGED PLANT AT THE STATEWIDE AIR POLLUTION RESEARCH CENTER, UNIVERSITY OF CALIFORNIA. PLANT - NARA - 542686.jpg
SMOG-DAMAGED PLANT AT THE STATEWIDE AIR POLLUTION RESEARCH CENTER, UNIVERSITY OF CALIFORNIA. PLANT - NARA - 542686.jpg

We can use clean tools to help. Using electric cars keeps air cleaner. We must work to keep our air safe.

113 words

Air pollution happens when harmful things get into the air.

Air pollution by industrial chimneys.jpg
Air pollution by industrial chimneys.jpg
These things can be gases or tiny bits of solid matter. We call these tiny bits particulate matter. Particulate matter is very dangerous to people.
How-many-people-die-from-air-pollution-1-1.png
How-many-people-die-from-air-pollution-1-1.png
Some pollution comes from outside. Burning fossil fuels for cars and power makes it.
Air pollution by industrial chimneys.jpg
Air pollution by industrial chimneys.jpg
Large factories also release smoke and gases. Dust storms and volcanoes can make the air dirty too.
Dust storm approaching Stratford, Texas.jpg
Dust storm approaching Stratford, Texas.jpg

Pollution can also happen inside homes. Many people burn wood or coal to cook and stay warm. This can make people sick.

Fish smoking in Ghana.jpg
Fish smoking in Ghana.jpg
Some pollutants are primary. This means they come straight from a source, like car exhaust. Other pollutants are secondary. These form in the air when different gases mix together. One example is ground-level ozone. This gas forms when sunlight hits certain chemicals.
SMOG-DAMAGED PLANT AT THE STATEWIDE AIR POLLUTION RESEARCH CENTER, UNIVERSITY OF CALIFORNIA. PLANT - NARA - 542686.jpg
SMOG-DAMAGED PLANT AT THE STATEWIDE AIR POLLUTION RESEARCH CENTER, UNIVERSITY OF CALIFORNIA. PLANT - NARA - 542686.jpg
Ozone can hurt crops and forests. We can help by using electric cars and clean energy.

183 words

Air pollution happens when harmful substances enter the air.

Air pollution by industrial chimneys.jpg
Air pollution by industrial chimneys.jpg
These substances can be gases, like ozone, or tiny bits of solid matter called particulate matter. Particulate matter is the most deadly type of pollution for people.
How-many-people-die-from-air-pollution-1-1.png
How-many-people-die-from-air-pollution-1-1.png
Pollution can exist both outdoors and indoors. Many people around the world face risks from poor air quality every day. This is a very important topic because it affects the health of all living things.
Air Quality (PM 2.5) Regional Overview.svg
Air Quality (PM 2.5) Regional Overview.svg

Pollution works in two different ways. Some substances are primary pollutants, which come straight from a source. For example, carbon monoxide comes directly from burning wood or gas.

Fish smoking in Ghana.jpg
Fish smoking in Ghana.jpg
Other substances are secondary pollutants. These are not sent out directly from a pipe or tailpipe. Instead, they form in the air when primary pollutants react with each other.
SMOG-DAMAGED PLANT AT THE STATEWIDE AIR POLLUTION RESEARCH CENTER, UNIVERSITY OF CALIFORNIA. PLANT - NARA - 542686.jpg
SMOG-DAMAGED PLANT AT THE STATEWIDE AIR POLLUTION RESEARCH CENTER, UNIVERSITY OF CALIFORNIA. PLANT - NARA - 542686.jpg
Ground-level ozone is a secondary pollutant that forms when sunlight hits certain chemicals. This can create smog in big cities.

Many different activities cause air pollution. Burning fossil fuels for electricity and transport is a major cause.

Air pollution by industrial chimneys.jpg
Air pollution by industrial chimneys.jpg
Cars and trucks also release nitrogen dioxide. In many homes, people burn firewood or coal to cook and stay warm.
Fish smoking in Ghana.jpg
Fish smoking in Ghana.jpg
This indoor smoke can be very harmful to women and young children. Agriculture also plays a part. For instance, cattle release methane when they digest food. Even natural events like dust storms and volcanoes can dirty the air.
Dust storm approaching Stratford, Texas.jpg
Dust storm approaching Stratford, Texas.jpg

History shows that countries are trying to fix this problem. In 1956, Britain passed the Clean Air Act.

DARK CLOUDS OF FACTORY SMOKE OBSCURE CLARK AVENUE BRIDGE - NARA - 550179.jpg
DARK CLOUDS OF FACTORY SMOKE OBSCURE CLARK AVENUE BRIDGE - NARA - 550179.jpg
Later, the United States passed its own Clean Air Act in 1963. These laws helped make the air cleaner in those places. On a global scale, the Montreal Protocol helped almost eliminate chemicals that hurt the ozone layer.
NASA - Human Fingerprint on Global Air Quality.webm
NASA - Human Fingerprint on Global Air Quality.webm
However, working together to stop climate change has been much harder.

Air pollution has a huge impact on our world. It is linked to many diseases like asthma and heart disease.

How-many-people-die-from-air-pollution-1-1.png
How-many-people-die-from-air-pollution-1-1.png
Every year, it causes 7 or 8 million deaths. This also costs the world economy over $8 trillion each year.
Share of deaths from indoor air pollution, OWID.svg
Share of deaths from indoor air pollution, OWID.svg
We can use new technology to help. Electric vehicles do not have tailpipe emissions.
Electric Rickshaws.jpg
Electric Rickshaws.jpg
Using renewable energy and clean cookers are also ways to keep our air healthy.

444 words

Air pollution is the presence of substances in the air that harm humans, living beings, or the environment. These substances, known as pollutants, can take several forms. They may be gases, such as ozone or nitrogen oxides. They can also be tiny solid or liquid particles called aerosols.

Portrait of Global Aerosols.jpeg
Portrait of Global Aerosols.jpeg
Pollution occurs both outdoors and indoors. Outdoor pollution often stems from industrial processes and transport. Indoor pollution frequently comes from household activities like cooking or heating. This issue is a major global challenge because it affects health, nature, and the economy.

Pollutants are classified by how they enter the atmosphere. Primary pollutants are produced directly by a source. Examples include carbon monoxide from car exhausts or sulfur dioxide from factories.

Air pollution by industrial chimneys.jpg
Air pollution by industrial chimneys.jpg
Secondary pollutants are not emitted directly from a source. Instead, they form in the air when primary pollutants react with each other or with other parts of the atmosphere. Ground-level ozone is a common secondary pollutant. It forms when nitrogen oxides and volatile organic compounds mix in the presence of sunlight.
SMOG-DAMAGED PLANT AT THE STATEWIDE AIR POLLUTION RESEARCH CENTER, UNIVERSITY OF CALIFORNIA. PLANT - NARA - 542686.jpg
SMOG-DAMAGED PLANT AT THE STATEWIDE AIR POLLUTION RESEARCH CENTER, UNIVERSITY OF CALIFORNIA. PLANT - NARA - 542686.jpg
This process often creates photochemical smog in large cities.

There are many distinct sources of air pollution. Transportation is a major contributor, especially road vehicles. These vehicles produce nitrogen dioxide and other emissions. Petrol and diesel engines release about half of their pollutants through exhaust gas. The other half comes from non-exhaust emissions like tire and brake wear.

Electric Rickshaws.jpg
Electric Rickshaws.jpg
Industry and construction also release significant amounts of dust and gases. For example, cement production is a major source of particle pollution. Agriculture is another massive source. Cattle emit methane during digestion, which contributes to ground-level ozone.
BurningOffFieldsInTheEveningInSouthGeorgia.jpg
BurningOffFieldsInTheEveningInSouthGeorgia.jpg
Additionally, the overuse of nitrogen fertilizers releases ammonia. Ammonia can react with other pollutants to form fine particulate matter.

Indoor air pollution is a specific and serious concern. As of 2023, over 2.3 billion people in developing countries rely on polluting fuels. These include firewood, agricultural waste, coal, or charcoal for cooking.

Fish smoking in Ghana.jpg
Fish smoking in Ghana.jpg
This type of pollution is particularly dangerous for women and young children. In some developed nations, wood stoves are a primary source of urban particulate pollution. Other indoor risks include biological materials like mold and pollen, or fumes from cleaning products. Even building materials can be a source, as some emit formaldehyde.

Natural events can also significantly impact air quality. Volcanic eruptions release sulfur dioxide and particle pollution into the sky.

Air pollution by industrial chimneys.jpg
Air pollution by industrial chimneys.jpg
Dust storms can carry pollution over vast distances. For instance, dust from the Gobi Desert can reach Hawaii. Wildfires are another major natural source of fine particles. These fires are becoming more common and severe due to climate change. Even vegetation plays a role, as certain trees emit gases that can raise ozone levels.

The consequences of air pollution are vast and measurable. It is a significant risk factor for diseases like asthma, heart disease, stroke, and lung cancer.

How-many-people-die-from-air-pollution-1-1.png
How-many-people-die-from-air-pollution-1-1.png
Particulate matter is considered the most deadly type of pollutant. Each year, air pollution kills between 7 and 8 million people. This has a massive economic impact as well. The World Bank estimates that premature deaths and lost productivity cost the global economy over $8 trillion annually.
Share of deaths from indoor air pollution, OWID.svg
Share of deaths from indoor air pollution, OWID.svg
Beyond humans, pollution damages ecosystems. Acid rain, caused by sulfur dioxide, can damage forests and erode structures.
Pollution - Damaged by acid rain.jpg
Pollution - Damaged by acid rain.jpg

History shows that laws and technology can help manage these risks. The 1956 Clean Air Act in Britain and the 1963 US Clean Air Act were effective national responses.

DARK CLOUDS OF FACTORY SMOKE OBSCURE CLARK AVENUE BRIDGE - NARA - 550179.jpg
DARK CLOUDS OF FACTORY SMOKE OBSCURE CLARK AVENUE BRIDGE - NARA - 550179.jpg
On an international level, the Montreal Protocol successfully helped almost eliminate ozone-depleting chemicals.
NASA - Human Fingerprint on Global Air Quality.webm
NASA - Human Fingerprint on Global Air Quality.webm
Today, many strategies aim to reduce pollution. These include using electric vehicles, renewable energy, and industrial scrubbers. Improved waste management and clean cookers also help protect the air we breathe.

698 words
🖼️ Images & Media (26)
File:Athlone cooling towers demolition 2010-08-22.gif
Athlone cooling towers demolition 2010-08-22.gif
File:Air pollution by industrial chimneys.jpg
Air pollution by industrial chimneys.jpg
File:BurningOffFieldsInTheEveningInSouthGeorgia.jpg
BurningOffFieldsInTheEveningInSouthGeorgia.jpg
File:Agbogbloshie,_Ghana_2019.jpg
Agbogbloshie,_Ghana_2019.jpg
File:Fish smoking in Ghana.jpg
Fish smoking in Ghana.jpg
File:Dust storm approaching Stratford, Texas.jpg
Dust storm approaching Stratford, Texas.jpg
File:Air Pollution-Causes&Effects.svg
Air Pollution-Causes&Effects.svg
File:SMOG-DAMAGED PLANT AT THE STATEWIDE AIR POLLUTION RESEARCH CENTER, UNIVERSITY OF CALIFORNIA. PLANT - NARA - 542686.jpg
SMOG-DAMAGED PLANT AT THE STATEWIDE AIR...
NASA - Human Fingerprint on Global Air...
File:Pollution de l'air.jpg
Pollution de l'air.jpg
File:Air Quality (PM 2.5) Regional Overview.svg
Air Quality (PM 2.5) Regional Overview.svg
File:Share-above-who-pollution-guidelines (OWID 0948).png
Share-above-who-pollution-guidelines...

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