Which Gases Contribute to the Greenhouse Effect?

The high amount of solar radiation striking the Earth can be categorized as visible light, ultraviolet and infrared. About 30 percent of this high radiation from the Sun is immediately reflected back out to space by clouds, glaciers and other reflective surfaces. The remaining part is absorbed by the atmosphere, the land and oceans.

“Greenhouse gases” are gas molecules that cause the Earth to become warmer by absorbing infrared radiation in the atmosphere of the planet. Gases such as Carbon dioxide (CO2), Methane (CH4), Hydrofluorocarbons (HFCs), Nitrous Oxide (N2O), Perfluorochemicals (PFCs), Sulfur hexafluoride (SF6) are called “greenhouse gases (GHGs)” because of the greenhouse effect they create.

What is The Greenhouse Effect?

Components in the Earth's atmosphere and the solar radiation reflected throughout the day warm the Earth. At night, they release this heat back into the atmosphere, causing the Earth to cool down. Greenhouse gases also trap some of the heat and keep the world at an average temperature of 15 degrees Celsius. In brief, the greenhouse effect is a natural process, and greenhouse gases actually create a greenhouse effect and keep the Earth's temperature in equilibrium. On the other hand, uncontrolled increase of these gases deflects the temperature of the Earth from its natural levels and process. This uncontrolled increase of the heat-trapping greenhouse gases due to human activities causes a material issue called ‘global warming’.

Some of the reasons behind the uneven and extreme warming of the Earth are as follows;
1. Population explosion
2. Fossil fuel use
3. Deforestation
4. Uneven consumption of resources

Unless these human activities, which disrupt the natural process of atmospheric gases, are taken under control, the temperature of the Earth will increase irreversibly and global warming will cause our world to become uninhabitable. Click for further details regarding the effects of Global Warming on Turkey.

Greenhouse gases not only cause environmental problems such as global warming and air pollution, but also cause numerous damages to human health.

Which Gases Cause the Greenhouse Effect?

Since the dawn of the Industrial Revolution in the 19th century, an accelerating and dangerous increase was observed in greenhouse gas emissions, and the global warming has begun to result in the climate change. Factory chimneys that rapidly increased during the Industrial Revolution emitted five major gases to the atmosphere which caused the greenhouse effect;

1. Water Vapor (H2O)
2. Carbon dioxide (CO2)
3. Methane (CH4)
4. Nitrous oxide (N2O)
5. Ozone (O3)

Water Vapor (H2O): Water vapor is the most abundant greenhouse gas in the atmosphere. Although this high water vapor concentration is not generated by human activities, more water vapor is trapped in our atmosphere and the air becomes humid due to the dangerous warming formed by other greenhouse gases. Trapping of heat in water molecules accelerates global warming.

Carbon dioxide (CO2): Majority of the anthropogenic greenhouse gas emissions are composed of carbon dioxide. Carbon dioxide is generated by burning of fossil fuels, i.e., coal, oil and natural gas, and is the main gas that causes the climate change when trapped in the atmosphere for a long time. The main natural phenomenon that reduces the percentage of CO2 in our atmosphere is forests. Thus, it is possible to say that protecting forests is the fundamental requirement in tackling global warming.

Methane (CH4): Methane is emitted into the atmosphere as a result of waste and livestock activities. The effect of methane gas, which composes 16% of greenhouse gases, on global warming is 25 times more than carbon dioxide. This is because methane gas has a very high capacity to retain infrared radiation. According to the research, 50%-65% of the methane gas in the atmosphere is attributed to anthropogenic sources.

Nitrous oxide (N2O): 40% of N2O emissions are attributed to anthropogenic sources such as fertilizer use (agricultural activities), domestic wastewater treatment, etc. Nitrous oxide, also called "laughing gas", stays in the atmosphere for more than 100 years when emitted. The percentage of nitrous oxide among greenhouse gases that cause global warming is about 6%.

Ozone (O3): The ozone layer in the stratosphere layer of the atmosphere protects life on Earth by absorbing the harmful radiation from the sun. When O3 is trapped in the troposphere layer of the atmosphere due to anthropogenic activities, it begins to pose a threat to humans and living species.

Greenhouse Gases (GHG) and The Climate Change

For millions of years, all components in the ecosystem of our planet have been connected to and in harmony with each other having a gentle equilibrium in the spirit of life. When a component in this ecosystem is damaged, the entire system begins to collapse with a domino effect. Although greenhouse gases are already present in the atmosphere at certain and varying rates, when their concentrations increase in an uncontrolled manner due to human activities (for example, destruction of forests, unconscious industrialization, use of synthetic fertilizers, uncontrolled population growth) the ecosystem begins to deteriorate. Thus, the Earth gets warm and the climate pattern changes.

How to Reduce GHG Emissions?

The major factor in the increase in global warming is human activities. Approaches such as guiding the social behaviors to environmental/nature protection, sustainability, and responsible consumption can reduce greenhouse gas emissions. In recent years, "Global Warming Potential", also referred to as GWP measurement, has been developed to determine the effects of greenhouse gases on global warming. GWP calculations take carbon dioxide (CO2) as reference. Moreover, the effect of a greenhouse gas over 100 years is calculated.

What are the Main Measures to Reduce GWP?

1. Reducing energy consumption and ensuring energy efficiency,​
Do you know what kind of measures you can take to save energy? Please check this article for further details.
2. Increasing the use of renewable energy instead of carbon-based energy systems and technologies,
3. Need-based consumption,
4. Regular use of the soil,
5. Waste reduction,
6. Promoting recycling,
7. Transition to environmentally friendly agriculture and livestock activities,
8. Reducing all emissions on a global scale.

Why We Should Reduce the Greenhouse Effect?

Although all the aforementioned measures include measures on a global and national scale, every human being shall raise awareness on global warming, reduce their domestic wastes, support EV use, and avoid excess consumption for the world to stay habitable.