Global warming is nothing but the warm-up of the earth’s surface. Earth absorbs most of the solar energy and it reflects back as infrared radiation. Greenhouse gases like CO2, methane, CFCs, and N2O in the atmosphere trap this heat by absorbing and reflecting the infrared radiation. This trapped energy falls on the earth’s surface, keeping it warmer, a process known as the greenhouse effect or global warming.
| S no. | Gases | % contribution to global warming (GW) |
| 1 | CO2 | 50 % |
| 2 | CH4 | 20 % |
| 3 | CFCs | 14 % |
| 4 | N2O | 5-7% |
Causes of global warming
- Natural sources of greenhouse gases: Like Wildfires, Organic matter decay, and Volcanic eruptions.
- Human activities as major contributors:
- Emissions from factories contain CFCs and automobiles.
- Burning of fuels
- Deforestation causes a rise in carbon monoxide
- Industrial processes waste
- Agricultural practices like methane gas from rice fields & livestock and nitrous oxide from nitrogen base fertilizer.
Effect of global warming on the world and agriculture:
- Global warming leads to increased temperatures, and it impacts on agriculture, as extreme heat can reduce crop yields, and negatively affect livestock health.
- Climate change alters precipitation patterns, causing shifts in rainfall distribution. Some regions may experience a risk of flooding, while others face more frequent droughts.
- Melting of ice caps and glaciers, resulting in rising sea levels. This causes a threat to coastal areas.
- Increased Frequency of Extreme Weather Events: such as intense rainfall, cyclones, hurricanes, and cyclones. These events can cause severe damage to livestock, crops, and overall agricultural productivity.
- Shifts in Growing Seasons and Plant Hardiness Zones: With changing climate conditions, the length and timing of growing seasons may shift. This impacts the choice of suitable crops and can disrupt established agricultural practices.
- Spread of Pests and Diseases: Warmer temperatures create favorable conditions for the spread of pests and diseases. This can negatively impact crop yields and quality.
Also visit the agro-climatic zones of India, list of agriculture colleges, types of farming systems, and agroecological zones of India
Signs of Global Warming or impact of global warming
- The melting of ice caps, glaciers, and polar ice is a significant sign of global warming.
- Increase in average global temperatures over time
- Global warming leads to the thermal expansion of water and the melting of land-based ice, resulting in rising sea levels.
- Increased carbon dioxide (CO2) levels in the atmosphere, caused by human activities, are absorbed by the oceans, leading to ocean acidification.
- Change in wind direction.
- Ozone depletion: The ozone layer, located around 19 to 30 km above the Earth’s surface, acts as a shield against harmful ultraviolet (UV) rays from the sun.
- Effect on ozone depletion:
- More ultraviolet (UV) radiation reaches the Earth’s surface due to thinning of the ozone layer.
- High UV radiation can damage the growth of the crops, which leads to a reduced crop yield. It also affects marine life.
- It also affects ecosystems and biodiversity.
- The presence of air pollutants, like sulfur dioxide (SO2) and Nitrogen oxides (NO2), primarily from industrial activities and burning fossil fuels combined with water to form sulfuric acid and nitric acid is called as acid rain.
- Impact of Acid Rain
- Deteriorates building that is made of rock.
- Acidification of soil and lakes.
Measures to control global warming
- Global warming can be controlled by shifting non-renewable energy into renewable energy like solar, wind, hydro, and geothermal power.
- Sustainable use of land forest conservation that protects from increased carbon dioxide from the atmosphere.
- Efficient use of waste management practices such as recycling, and composting.
- Promote public transport, cycling, and walking to avoid greenhouse gas emissions.
- Industrial emissions control.
