Global Environment Change

Natural environment and climate are inherently dynamic and change over the course of time; but human population growth, industrialisation, and the associated anthropogenic activities have made these changes far more pronounced and impactful within a much shorter time span, producing what is termed drastic global environmental change. Large-scale changes of this kind can trigger a wide range of hazards, including climate change, stratospheric ozone depletion, changes in ecosystems from biodiversity loss, changes in hydrological systems and freshwater supplies, land degradation, urbanisation, and added stress on food-producing systems. The underlying mechanism is the greenhouse effect: greenhouse gases (GHGs) -- water vapour, carbon dioxide, methane, nitrous oxide, ozone, and artificial chemicals such as chlorofluorocarbons (CFCs) -- absorb outgoing radiant energy, and this absorbed energy warms both the atmosphere and Earth's surface. The consequences of large-scale global warming are significant for both people and nature: as global average temperatures rise, precipitation patterns can be disrupted, producing extreme wet and dry conditions (flooding on one hand, desertification on the other); coastal areas become more vulnerable to storm surges as sea levels rise; and plant and animal species are forced to migrate or face local disappearance in response to shifting climate conditions. Global warming can also directly affect flora and fauna in ways that create food shortages or even food crises, in turn affecting the health of both people and other organisms -- a concrete, India-specific example being the endangered Nilgiri Tahr, projected to lose roughly 60% of its habitat starting from the 2030s as a direct result of climate change. In response, the United Nations has organised a long sequence of international conventions …