Climate change refers to long-term shifts in temperatures and weather patterns. While these shifts can be natural, since the Industrial Revolution, human activities have been the dominant cause of climate change. This is primarily due to the increase in greenhouse gas concentrations in the atmosphere.
Causes of Global Climate Change
The primary causes of global climate change are:
Greenhouse Gas Emissions: Gases like carbon dioxide ($CO_2$), methane ($CH_4$), and nitrous oxide ($N_2O$) trap heat in the atmosphere.
Burning Fossil Fuels: The burning of coal, oil, and natural gas for energy releases large amounts of $CO_2$.
Deforestation: Trees absorb $CO_2$. When forests are cut down, this stored carbon is released back into the atmosphere.
Agriculture: Agricultural practices, particularly livestock farming and the use of fertilizers, release $CH_4$ and $N_2O$.
Industrial Processes: Some industrial processes release greenhouse gases.
The following table summarizes the major greenhouse gases and their approximate global warming potentials (GWPs) relative to $CO_2$:
Greenhouse Gas
Chemical Formula
Approximate GWP
Carbon Dioxide
$CO_2$
1
Methane
$CH_4$
25
Nitrous Oxide
$N_2O$
298
Fluorinated Gases
Various
Thousands (depending on the gas)
Effects of Global Climate Change
The effects of climate change are wide-ranging and are already being observed globally. These include:
Rising Global Temperatures: The average temperature of the Earth is increasing.
Changes in Precipitation Patterns: Some areas are experiencing more rainfall and flooding, while others are facing more droughts.
Melting Glaciers and Ice Sheets: This contributes to rising sea levels.
Rising Sea Levels: This threatens coastal communities and ecosystems.
Increased Frequency and Intensity of Extreme Weather Events: This includes heatwaves, storms, floods, and droughts.
Ocean Acidification: The absorption of excess $CO_2$ by the oceans makes them more acidic, harming marine life.
Changes in Ecosystems and Biodiversity: Species are struggling to adapt to the changing climate, leading to shifts in distribution and potential extinctions.
Suggested diagram: A diagram illustrating the greenhouse effect, showing solar radiation entering the atmosphere, some being reflected, and some being trapped by greenhouse gases.
The impacts of climate change are not evenly distributed. Developing countries are often more vulnerable due to their limited resources and infrastructure.