What is a pollutant in the troposphere?
Ozone and other air pollutants are common in urban areas in late afternoon. But in the troposphere, near ground-level, ozone molecules are both air pollutants, threatening the health of living things, and greenhouse gases, trapping heat and contributing to climate change. …
Is o2 a pollutant in the troposphere?
About 21% of Earth’s atmosphere is oxygen. Oxygen can also form a molecule of three atoms, which is known as ozone (O3). Ozone in Earth’s stratosphere plays a helpful role by blocking most of the harmful UV radiation from the Sun, while ozone in the troposphere is a hazardous pollutant.
What gas is a pollutant in the troposphere?
Ozone (O3) is a reactive gas that exists in two layers of the atmosphere: the stratosphere (upper layer) and the troposphere (at ground level and up to 15km). In the stratosphere, ozone protects life on Earth from the sun’s ultraviolet radiation.
What things are in the troposphere?
The troposphere is made up of approximately 78% nitrogen, 21% oxygen, and 1% other gases, which include carbon dioxide, methane, neon, krypton, argon, helium, and hydrogen. The troposphere contains approximately 99% of the water vapour in the earth’s entire atmosphere.
Why is the pollution is created in this layer?
This is due to the absorption of infrared radiation from the surface by water vapor and other greenhouse gases (e.g. carbon dioxide, nitrous oxide and methane) in the troposphere. Dust and pollutants injected into the troposphere become well mixed in the layer, but are eventually washed out by rainfall.
How does the tropospheric ozone form in the atmosphere?
It does not have any direct emissions sources, rather it is a secondary gas formed by the interaction of sunlight with hydrocarbons – including methane – and nitrogen oxides, which are emitted by vehicles, fossil fuel power plants, and other man-made sources.
What are precursor pollutants created by human activities?
Precursor pollutants created by human activities include hydrocarbons and nitrogen oxides, which are largely emitted by cars and other vehicles, fossil fuel power plants, oil refineries, the agriculture sector and a number of other industries. Ozone absorbs radiation and consequently acts as a strong greenhouse gas.
How many premature deaths are caused by tropospheric ozone?
Tropospheric ozone exposure is responsible for an estimated one million premature deaths each year. Children, the elderly, and people with lung or cardiovascular diseases are particularly at risk of the adverse health impacts of ozone.