Human causes - SS3 Geography Lesson Note

Human activities have significantly contributed to these changes, primarily through:

 

Greenhouse Effect: The greenhouse effect is a natural process where certain gases in the Earth's atmosphere, known as greenhouse gases (e.g., carbon dioxide, methane, and water vapor), trap heat from the sun. This helps keep the planet's temperature at a habitable level. However, human activities, such as burning fossil fuels and deforestation, have increased the concentration of these gases, enhancing the natural greenhouse effect and causing the Earth's temperature to rise.

 

Ozone Layer Depletion: Ozone is a protective layer in the Earth's stratosphere that absorbs and blocks harmful ultraviolet (UV) radiation from the sun. Human-made chemicals, like chlorofluorocarbons (CFCs) found in aerosol sprays and refrigerants, have been responsible for ozone layer depletion. This depletion allows more UV radiation to reach the Earth's surface, which can have harmful effects on both the environment and human health.

 

Chlorofluorocarbon (CFC) Gases: CFCs are synthetic compounds that were widely used in refrigeration, air conditioning, and aerosol propellants. These compounds are stable in the lower atmosphere but eventually release chlorine when they reach the stratosphere. This chlorine then contributes to the breakdown of ozone molecules, leading to ozone layer depletion.

 

Carbon Emissions: The burning of fossil fuels (coal, oil, and natural gas) for energy and transportation is a major source of carbon emissions in the form of carbon dioxide (CO2). Increased carbon dioxide levels in the atmosphere enhance the greenhouse effect and contribute to global warming.

 

Deforestation: Deforestation is the large-scale clearing of forests, primarily for agriculture, urbanization, and logging. Trees play a vital role in absorbing carbon dioxide from the atmosphere. When forests are cut down, the stored carbon is released into the atmosphere, further contributing to rising CO2 levels and climate change.

 

Gas Flaring: Gas flaring is the process of burning off excess natural gas during oil extraction and production. This releases methane and carbon dioxide into the atmosphere, both of which are potent greenhouse gases, contributing to global warming.

 

These factors collectively contribute to the phenomenon of climate change, resulting in long-term alterations to the Earth's climate system with various adverse impacts on ecosystems, weather patterns, and human societies.