ENVIRONMENT GEOGRAPHY TERMS

PRERNA FOR IAS

ENVIRONMENT GEOGRAPHY TERMS

1. Carbon Cycle

The carbon cycle is the continuous movement of carbon among the atmosphere, oceans, soil, rocks, and living organisms. Plants absorb 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, and combustion of fossil fuels. Oceans also absorb and release large amounts of carbon dioxide. The carbon cycle helps regulate Earth’s climate and supports life processes. Human activities such as deforestation and burning fossil fuels have increased atmospheric carbon dioxide, contributing to global warming and climate change worldwide.

2. Nitrogen Cycle

The nitrogen cycle is the process through which nitrogen moves between the atmosphere, soil, plants, animals, and microorganisms. Atmospheric nitrogen cannot be directly used by most organisms. Nitrogen-fixing bacteria convert it into usable forms such as ammonia. Through nitrification, ammonia becomes nitrates that plants absorb. Animals obtain nitrogen by eating plants. When organisms die, decomposers return nitrogen to the soil through ammonification. Denitrifying bacteria convert nitrates back into atmospheric nitrogen. This cycle is essential for protein and DNA formation in living organisms. The nitrogen cycle maintains soil fertility and supports agricultural productivity and ecosystem stability.

3. Hydrological Cycle

The hydrological or water cycle describes the continuous circulation of water on Earth. Water evaporates from oceans, rivers, lakes, and soil, while plants release moisture through transpiration. Water vapour rises, cools, and condenses into clouds. Eventually, precipitation occurs as rain, snow, or hail. Some water infiltrates into the ground, replenishing groundwater, while the rest flows as surface runoff into rivers and oceans. The cycle continuously renews freshwater resources and regulates climate. It is vital for agriculture, ecosystems, and human survival. Solar energy drives this natural process, ensuring the distribution and recycling of water globally.

4. Greenhouse Effect

The greenhouse effect is a natural process that warms Earth’s surface and lower atmosphere. Certain gases, including carbon dioxide, methane, nitrous oxide, and water vapour, trap heat radiated from the Earth's surface. This trapped heat maintains a suitable temperature for life. Without the greenhouse effect, Earth would be too cold for most living organisms. However, human activities such as industrialization, deforestation, and fossil fuel burning have increased greenhouse gas concentrations. This enhanced greenhouse effect causes excessive warming and contributes to climate change. Understanding the greenhouse effect is important for managing environmental sustainability and global climate stability.

5. Global Warming

Global warming refers to the long-term increase in Earth's average surface temperature due to rising concentrations of greenhouse gases. Human activities such as burning coal, oil, and natural gas release large amounts of carbon dioxide into the atmosphere. Deforestation further reduces carbon absorption by plants. Global warming causes melting glaciers, rising sea levels, extreme weather events, and shifts in ecosystems. It affects agriculture, water resources, biodiversity, and human health. Scientists consider global warming one of the greatest environmental challenges of the modern era. International cooperation and emission reduction measures are essential to limit its harmful impacts.

6. Climate Change