OZONE DEPLETION-2

PRERNA FOR IAS

         Mehnat Aapki, Guidance Humari

         Roz ki Prelims Practice — Experts ke Saath

OZONE DEPLETION-2

1. Dobson Unit (DU)

The Dobson Unit (DU) is the standard unit used to measure the total amount of ozone present in a vertical column of the Earth's atmosphere. It was named after British physicist Gordon M. B. Dobson, who pioneered ozone measurement. One Dobson Unit represents a layer of pure ozone 0.01 millimetres thick at standard temperature and pressure. The global average ozone concentration is about 300 DU. Lower values indicate ozone depletion, while values below 220 DU generally signify the presence of an ozone hole. Dobson Units are essential for monitoring changes in the ozone layer and environmental protection.

2. Ozone Hole

An ozone hole refers to a region where the ozone concentration in the stratosphere falls below 220 Dobson Units (DU). It occurs mainly over Antarctica during the Southern Hemisphere's spring (September–November). Extremely cold temperatures allow the formation of polar stratospheric clouds, where chlorine and bromine released from CFCs react and destroy ozone molecules rapidly. The ozone hole increases harmful UV-B radiation reaching the Earth's surface, affecting humans, plants, and marine ecosystems. International efforts under the Montreal Protocol have significantly reduced ozone-depleting substances, and scientific observations indicate that the ozone hole is gradually recovering.

3. National Action Plan on Climate Change (NAPCC)

The National Action Plan on Climate Change (NAPCC) was launched by the Government of India on 30 June 2008 under Prime Minister Dr. Manmohan Singh. It provides a comprehensive strategy to address climate change while promoting sustainable economic development. The Ministry of Environment, Forest and Climate Change (MoEFCC) coordinates its implementation. The plan consists of eight national missions, each focusing on renewable energy, energy efficiency, sustainable agriculture, water conservation, Himalayan ecosystem protection, forestry, sustainable habitat, and climate knowledge. NAPCC seeks to reduce greenhouse gas emissions, improve climate resilience, and ensure environmentally sustainable development in India.

4. National Solar Mission