Previous Year Question

Climate Change refers to long-term changes in the Earth's temperature, precipitation, Atmospheric Circulation, and other climatic conditions. Its major contributing factors include increasing concentrations of Greenhouse Gases, Atmospheric Pollution, and processes associated with changes in the Ozone Layer. Industrialization, fossil fuel combustion, deforestation, and agricultural activities have increased the emissions of substances that affect the climate. The primary cause of current Global Warming is the increasing concentration of greenhouse gases resulting from human activities.

Greenhouse Gases are among the principal drivers of Climate Change. Carbon Dioxide (CO₂), Methane (CH₄), Nitrous Oxide (N₂O), and fluorinated gases enhance the Greenhouse Effect by absorbing Infrared Radiation emitted from the Earth's surface. This increases the temperature of the Earth's surface and lower atmosphere. Fossil fuel combustion is a major human source of CO₂ emissions, while livestock farming, rice cultivation, and fossil fuel production release Methane. Emissions of N₂O from agricultural soils and nitrogen-based fertilizers also contribute to Climate Change.

Ozone Layer Depletion can also influence atmospheric temperatures and circulation. Ozone present in the Stratosphere absorbs harmful Ultraviolet Radiation from the Sun. Chlorine and Bromine released from substances such as Chlorofluorocarbons (CFCs) and Halons cause the destruction of ozone molecules. A reduction in ozone concentration can lead to Stratospheric Cooling and changes in Atmospheric Circulation. However, scientifically, ozone layer depletion is not a primary cause of Global Warming; its direct climatic influence is much smaller than that of greenhouse gases.

Atmospheric Pollution also influences climate through different mechanisms. For example, Black Carbon absorbs solar radiation and contributes to warming, whereas Sulfate Aerosols reflect sunlight and can produce a cooling effect. Certain pollutants also influence atmospheric ozone formation and cloud properties. Climate Change can result in glacier melting, sea-level rise, changes in precipitation patterns, and variations in the intensity of extreme weather events.