ENVIRONMENT GEOGRAPHY TERMS-2

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         Mehnat Aapki, Guidance Humari

         Roz ki Prelims Practice — Experts ke Saath

ENVIRONMENT GEOGRAPHY TERMS-2

1. Carbon Cycle

The Carbon Cycle is the continuous movement of carbon among the atmosphere, oceans, soil, rocks, and living organisms. Plants absorb atmospheric carbon dioxide during photosynthesis and convert it into organic matter. Animals obtain carbon by consuming plants or other animals. Carbon returns to the atmosphere through respiration, decomposition, volcanic eruptions, and the burning of fossil fuels. Oceans also absorb and release carbon dioxide, acting as major carbon reservoirs. Human activities such as deforestation and industrial emissions have increased atmospheric carbon dioxide, contributing to climate change. Maintaining a balanced carbon cycle is essential for climate regulation and sustaining life.

2. Nitrogen Cycle

The Nitrogen Cycle is the natural circulation of nitrogen between the atmosphere, soil, plants, animals, and microorganisms. Although nitrogen makes up about 78% of Earth's atmosphere, most organisms cannot use it directly. Nitrogen-fixing bacteria convert atmospheric nitrogen into ammonia, which is further transformed into nitrates through nitrification. Plants absorb nitrates to produce proteins, while animals obtain nitrogen by eating plants or other animals. Decomposers return nitrogen to the soil, and denitrifying bacteria convert nitrates back into atmospheric nitrogen. The nitrogen cycle maintains soil fertility, supports agriculture, and ensures continuous nutrient recycling in ecosystems.

3. Hydrological Cycle

The Hydrological Cycle, also known as the Water Cycle, is the continuous movement of water between the Earth's surface and the atmosphere. Water evaporates from oceans, lakes, and rivers due to solar energy. Plants release water vapour through transpiration. Water vapour condenses into clouds and returns to Earth as precipitation such as rain or snow. Some water infiltrates into the ground, while the rest flows as runoff into rivers and oceans. This cycle regulates Earth's climate, replenishes freshwater resources, supports ecosystems, and maintains the availability of water for agriculture, industry, and human consumption.

4. Greenhouse Effect

The Greenhouse Effect is the natural process by which certain gases in the atmosphere trap heat and keep the Earth warm enough to support life. Greenhouse gases such as carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), and water vapour absorb outgoing infrared radiation and re-radiate it toward the Earth's surface. Without the natural greenhouse effect, Earth's average temperature would be about –18°C, making life impossible. However, excessive greenhouse gas emissions caused by human activities enhance this effect, leading to global warming and climate change. Maintaining a balanced greenhouse effect is essential for environmental stability.

5. Global Warming

Global warming refers to the long-term increase in Earth's average surface temperature due to the enhanced greenhouse effect caused mainly by human activities. Burning fossil fuels, deforestation, industrialization, and agriculture release large amounts of greenhouse gases into the atmosphere. Rising temperatures lead to melting glaciers, sea-level rise, changing rainfall patterns, stronger heatwaves, and loss of biodiversity. Global warming also affects agriculture, human health, and freshwater availability. Reducing greenhouse gas emissions, increasing renewable energy use, protecting forests, and promoting sustainable lifestyles are important strategies for limiting global warming and reducing its environmental impacts.

6. Climate Change