Greenhouse gases are gases in the Earth’s atmosphere that trap heat, they allow sunlight in and prevent part of heat brought by sunlight from leaving the atmosphere. This is ‘greenhouse effect’ that keeps our planet warm enough to support life. However, when the concentration of these gases increases beyond natural level, it leads to global warming and climate changes which are harmful to both nature and human.

1. Carbon Dioxide (CO₂): burning fossil fuels (coal, oil, and natural gas), deforestation, industrial processes, transportation, etc.
2. Methane (CH₄): landfills, agriculture (especially livestock digestion), oil and gas extraction, etc.
3. Nitrous Oxide (N₂O): agricultural fertilizers, sewage treatment, industrial processes, etc.
4. Fluorinated Gases: refrigeration, air conditioning, manufacturing processes, etc.
These gases differ in how strongly they trap heat and how long they can stay in the atmosphere. Scientists always use the method called global warming potential (GWP) measurement to compare them.

When GHGs accumulate in the atmosphere, they gradually enhance the natural greenhouse effect by trapping more heat, and this results in higher Earth’s average temperature. This process, known as anthropogenic (human-caused) global warming, may lead to: melting glaciers and rising sea levels, extreme weather events (heatwaves, hurricanes, droughts), ocean acidification, disruption of ecosystems and biodiversity, etc.

While GHGS are essential for life, excessive human-induced emissions would cause harmful climate disruptions. To reduce greenhouse gas emissions and combat climate change, we must take collective action toward sustainable solutions and low-carbon technologies.