The ozone layer, consisting of ozone molecules (a three-oxygen molecule), is crucial for life on Earth as it shields the planet from harmful ultraviolet (UV) radiation from the sun. Found primarily in the stratosphere, the ozone layer's protection against UV rays is essential for preventing skin cancer, cataracts, and other health issues in humans, as well as protecting ecosystems and wildlife.

Causes of Ozone Layer Depletion:

• Chlorofluorocarbons (CFCs) and Halons: These synthetic chemicals were widely used in refrigerants, air conditioning systems, foam insulation, and fire extinguishers. When released into the atmosphere, CFCs and Halons break down ozone molecules in the stratosphere, leading to ozone depletion.
• Halo-carbons and Other Ozone-Depleting Substances: Besides CFCs and Halons, other ozone-depleting substances like carbon tetrachloride, hydrochlorofluorocarbons (HCFCs), methyl chloroform, methyl bromide, and bromochloromethane contribute to the destruction of the ozone layer. These chemicals have varying atmospheric lifetimes but collectively pose a threat to ozone stability.
• Chemical Reactions: Ozone depletion occurs due to complex chemical reactions involving ozone and ozone-depleting substances. For instance, chlorine and bromine atoms released from CFCs and Halons catalytically break down ozone molecules, reducing the ozone concentration in the stratosphere.

Efforts to Address Ozone Depletion:

• Montreal Protocol: Recognizing the severity of ozone layer depletion, the international community established the Montreal Protocol in 1987. This treaty aimed to phase out the production and consumption of ozone-depleting substances. Over time, significant progress has been made in reducing the use of CFCs, Halons, and other harmful chemicals regulated under the protocol.
• Replacement Technologies: The Montreal Protocol led to the development and adoption of alternative substances that do not harm the ozone layer. For example, hydrofluorocarbons (HFCs) are used as substitutes for CFCs in many applications, as they have zero ozone-depleting potential.

Kigali Agreement

India’s effort