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What is stratospheric depletion?

What is stratospheric depletion?

The dramatic depletion of stratospheric ozone in polar regions is caused by a combination of anthropogenic emissions of ozone-depleting substances, stable circulation patterns, extremely low temperatures and solar radiation.

Where is stratospheric ozone depletion?

One example of ozone depletion is the annual ozone “hole” over Antarctica that has occurred during the Antarctic spring since the early 1980s. This is not really a hole through the ozone layer, but rather a large area of the stratosphere with extremely low amounts of ozone.

What chemicals cause stratospheric ozone depletion?

Ozone depletion occurs when chlorofluorocarbons (CFCs) and halons—gases formerly found in aerosol spray cans and refrigerants—are released into the atmosphere (see details below).

What are the steps in stratospheric ozone depletion?

The stratospheric ozone depletion process begins with the emission of halogen source gases by human activities and natural processes. Those emitted by human activities are also called ozone-depleting substances (ODSs). Subsequent steps are accumulation, transport, conversion, chemical reaction, and removal.

What are 3 causes of depletion to the ozone layer?

Chlorofluorocarbons or CFCs are the main cause of ozone layer depletion. These are released by solvents, spray aerosols, refrigerators, air-conditioners, etc. The molecules of chlorofluorocarbons in the stratosphere are broken down by the ultraviolet radiations and release chlorine atoms.

What is meant by stratospheric?

stratospheric adjective (OF ATMOSPHERE) environment specialized. relating to the stratosphere (= the layer of gases surrounding the earth at a height of between 15 and 50 kilometres): stratospheric clouds.

What are the reasons for depletion of ozone layer?

The main cause of ozone depletion and the ozone hole is manufactured chemicals, especially manufactured halocarbon refrigerants, solvents, propellants, and foam- blowing agents (chlorofluorocarbons (CFCs), HCFCs, halons).

What is the first step in the destruction of ozone?

The initial step in the depletion of stratospheric ozone by human activities is the emission, at Earth’s surface, of ozone-depleting gases containing chlorine and bromine. Most of these gases accumulate in the lower atmosphere because they are unreactive and do not dissolve readily in rain or snow.

What is the function of stratospheric ozone?

Stratospheric ozone is a naturally-occurring gas that filters the sun’s ultraviolet (UV) radiation. This is typically regarded as ‘good’ ozone since it reduces the harmful effects of ultraviolet (UV-B) radiation. A diminished ozone layer allows more radiation to reach the Earth’s surface.

What causes the ozone hole?

The ozone hole has developed because people have polluted the atmosphere with chemicals containing chlorine and bromine. The primary chemicals involved are chlorofluorocarbons (CFCs for short), halons, and carbon tetrachloride. Once released from CFCs, chlorine (Cl) then reacts with ozone (O3) to form ClO and O2.

How are humans affecting the ozone layer?

Human activities cause the emission of halogen source gases that contain chlorine and bromine atoms. These emissions into the atmosphere ultimately lead to stratospheric ozone depletion. Because of these uses, halons are often directly released into the atmosphere.

What is another word for stratospheric?

In this page you can discover 15 synonyms, antonyms, idiomatic expressions, and related words for stratospheric, like: unconscionable, tropospheric, sky-high, steep, stiff, big, usual, mesospheric, stratosphere, troposphere and lower-atmosphere.

What is the ODP of stratospheric ozone?

The ODP is a number which refers to the amount of stratospheric ozone depletion caused by a substance. In this regard, ODP was treated as the ratio of the impact on ozone of a chemical compared to the impact of a similar mass of R-11. Thus, the ODP of R-11 was defined to be 1.0.

What happens to ODS in the troposphere?

ODS are generally very stable in the troposphere and only degrade under intense ultraviolet light in the stratosphere. When they break down, they release chlorine or bromine atoms, which then deplete ozone.

How does low stratospheric ozone affect the environment?

Impact of low stratospheric ozone on the natural environment. Increases in Ultra Violet (UVB) radiation caused by reductions in stratospheric ozone concentrations are associated with effects on Biogeochemical cycles – balance between production and destruction of organic matter.

Which is less potent at destroying the ozone layer, CFCs or HCFCs?

Although ozone depleting substances, they are less potent at destroying stratospheric ozone than chlorofluorocarbons (CFCs). They have been introduced as temporary replacements for CFCs and are also greenhouse gases. See ozone depleting substance. (HCFCs).