by Maria Mazzoli, – Art in Tanzania internship
What is pollution?
•Pollution is the introduction of harmful materials into the environment. These harmful materials are called pollutants.
•Trash and runoff produced by factories are examples of pollutants created by human activity.
•Pollutants damage the quality of air, water and land.
•Many things that are useful to people produce pollution (cars spew pollutants from their exhaust pipes).
•All living things depend on Earth’s air and water. When these resources are polluted, all forms of life are threatened.
Pollution is a global problem:
Although urban areas are more polluted than the countryside, pollution can spread to remote places where no people live.
In the middle of the northern Pacific Ocean, a huge collection of microscopic plastic particles forms what is known as the Great Pacific Garbage Patch.
Air and water currents carry pollution.
. Which are the different types of pollution?
We can identify several types of pollution on Earth:
• The main sources of air pollution are gases pouring from the exhaust pipes of factories and burning fossil fuels (coal, oil, and natural gas).
• When fossil fuels are burned, they produce carbon monoxide, a colorless, odorless gas, which is harmful in high concentration.
• Polluted air makes people’s eyes burn and make them have difficulty breathing.
Polluted water looks muddy, smells bad, and has garbage floating in it.
Some polluted water looks clean, but it is filled with harmful chemicals you can’t see or smell.
Polluted water is unsafe for drinking and swimming.
Sometimes, people get sick because they eat fish that lived in polluted water.
Sources of water pollution:
•When Chemicals and oils from factories are dumped into waterways, they create a toxic environment for aquatic life. •Mining and drilling can also contribute to water pollution.
=>Acid helps miners to remove coal from the rocks, but when it is washed into rivers, it releases chemical sulfur, which is toxic to plants, fish, and humans.
=>Oil spills can produce large plumes of oil under the sea and oil slick on the surface killing marsh plants and aquatic organisms
=>In 2010 more than 2 million animals died as a result of the Deep-water Horizon oil spill.
Fertilizer is material added to soil to make plants grow larger and faster.
Rainwater washes fertilizers into streams and lakes, where chemicals contained in the fertilizers cause harmful algal blooms.
There are certain rivers that have so much garbage floating in them that you cannot even see the water.
Floating trash makes it difficult to fish in.
Trash is a threat to fish and seabirds, which mistake the plastic for food.
•Many of the same pollutants that foul the water also harm the land.
•Mining leaves the soil contaminated with dangerous chemicals.
•Pesticides and fertilizer from agriculture are blown by the wind, and can harm plants, animals and people.
•Trash mar the landscape. Litter makes it difficult for plants to grow well. Garbage contains pollutants as oil, chemicals and ink.
Focus on Greenhouse gases (GHGs):
GHGs are the main source of air pollution.
GHGs such as carbone dioxide (CO2) and methane (CH4) occur naturally in the atmosphere.
They absorb sunlight reflected from earth, preventing it from escaping into space.
By trapping heat in the atmosphere, they keep Earth warm enough for people to live. This is called greenhouse effect.
What happens when the level of GHGs is too high?
Some human activities, such as burning fossil fuels, increase the amount of GHGs in the atmosphere.
More GHGs in the atmosphere result in increased heat across the globe.
This is called global warming.
Global warming is causing ice sheets and glaciers to melt.
Melting ice is causing sea levels to rise.
This will flood low-lying coastal regions.
Entire regions (such as Maldives) are threatened by this climate change.
Global warming also contributes to the process of ocean acidification.
It means that the ocean absorbs more CO2 from the atmosphere and becomes acid.
The ocean food web is threatened as plants and animals such as coral fail to adapt to more acid oceans.
Global warming is causing increases in storms, droughts, and flooding.
Since more greenhouse gas emissions are released into the air, causing air temperatures to increase, more moisture evaporates from land and lakes, rivers, and other bodies of water.
Warmer temperatures also increase evaporation in plant soils, which affects plant life and can reduce rainfall even more.
And when rainfall does come to drought-stricken areas, the drier soils it hits are less able to absorb the water, increasing the likelihood of flooding.
The commitment of the International community:
The Paris Agreement is the most recent international treaty on climate change.
It was adopted by 196 countries (among which Tanzania) in Paris (France), on 12 December 2015.
Its goal is to limit global warming, by reducing greenhouse gases.
Tanzania’s commitment includes adaptation and mitigation measures such as planting adequate trees and sustainably using existing forest and woodland resources.