BlogGreenhouse Gases (GHGs)
What are Greenhouse Gases (GHGs)?
GHGs are gases in the Earth’s atmosphere that make it harder for the heat to escape.
Warming of the Earth’s surface happens throughout the day when the sun shines through the atmosphere. Then that heat is released back into the air at night cooling the Earth’s surface. However, due to the effects of the greenhouse gases, not all the heat is released, effectively, trapping the heat in the atmosphere. That's what keeps the earth’s temperature at an average of 14˚C (57˚F).
Greenhouse gases and the greenhouse effect
Interchangeable terms such as greenhouse, glasshouse, or hothouse refer to the structures designed to create a favorable and regulated environment inside by controlling temperature and humidity. The principle behind this is that walls and roofs that are made of transparent materials (usually polycarbonate, plastic film made of polyethylene, or glass panes) capture sunlight and heat.
Similar to the glass walls of a greenhouse, gases trap the heat - hence the name, greenhouse gases. This greenhouse effect makes sure that Earth’s temperature does not become too cold, to the point where it can no longer sustain life.
However, human activities like the Industrial Revolution have caused a drastic increase in the release of greenhouse gases into the atmosphere. As a result, Earth’s natural greenhouse effect has changed.
Different types of GHGs
Carbon dioxide
CO2 is released through natural processes, such as volcanic eruptions, plant respiration, and animal and human breathing. But the atmospheric CO2 concentration has increased by 50% since the Industrial Revolution began in the 1800s, due to human activities like the burning of fossil fuels and large-scale deforestation. Due to its abundance, CO2 is the main contributor to climate change.
Methane
Methane is produced naturally through decomposition. But again, human activity has displaced the natural balance. Large amounts of methane are released by cattle farming, landfill waste dumps, rice farming and the traditional production of oil and gas.
Nitrous oxide
Nitrous oxide is produced through the large-scale use of commercial and organic fertilisers, fossil-fuel combustion, nitric-acid production, and biomass burning.
Water vapour
Water vapour is the most abundant greenhouse gas. It increases as the earth's atmosphere warms but unlike CO2, which can remain in the earth’s atmosphere for centuries, water vapour persists for only a few days.
Industrial fluorinated gases - hydrofluorocarbons (HFC), perfluorocarbons (PFC), and sulphur hexafluoride (SF6)
Those are man-made gases during industrial processes and do not occur in nature. Their effectiveness in heat-trapping is much higher than naturally produced gases described above. For example, SF6 is 23,500 times more potent than CO2.