In which sphere ozone layer depletion is found?

In which sphere ozone layer depletion is found?

Most atmospheric ozone is concentrated in a layer in the stratosphere, about 9 to 18 miles (15 to 30 km) above the Earth’s surface (see the figure below). Ozone is a molecule that contains three oxygen atoms. At any given time, ozone molecules are constantly formed and destroyed in the stratosphere.

Which is most harmful for ozone depletion?

Chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and halons destroy the earth’s protective ozone layer, which shields the earth from harmful ultraviolet (UV-B) rays generated from the sun.

How do HCFCs destroy ozone?

A certain portion of HCFC molecules released to the atmosphere will reach the stratosphere and be destroyed there by photolysis (light-initiated decomposition). The chlorine released in the stratosphere can then participate in ozone depleting reactions as does chlorine liberated from the photolysis of CFCs.

What is the evidence for ozone depletion?

In the 1970s, scientists noticed that the ozone layer was thinning. Researchers found evidence that linked the depletion of the ozone layer to the presence of chlorofluorocarbons (CFCs) and other halogen-source gases in the stratosphere.

What is bad ozone?

The “bad” ozone or ground-level ozone is sourced from human activity. This harmful air pollutant affects people, the environment and is the main ingredient in “smog”.

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 causing the ozone hole?

Reasons for 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.