Greenhouse gases and the positive and negative effects they have on our life on Earth have lately become buzzwords more than scientific terms. What are they and how does the ‘effect’ work?
Let’s start by saying that without the greenhouse gas effect, there would be no life on Earth. Greenhouse gases are essential for trapping heat in our atmosphere, which makes the average temperature on Earth about 15 degrees Celsius compared to -18 degrees Celsius without greenhouse gases, preventing us from freezing at night. Our atmosphere works as a shield that blocks most harmful solar rays; gases that make up the ozone layer help with this.
What are greenhouse gases?
Most of our atmosphere is composed of nitrogen and oxygen. While essential for life, neither of these can absorb infrared radiation coming from the sun because their molecular structure just doesn’t allow them to.
Greenhouse gases include carbon dioxide (CO₂), methane (CH₄), nitrous oxide (N₂O), fluorinated gases, and water vapour (H2O). These are critical to maintaining Earth’s temperature by absorbing and re-radiating infrared radiation - a process which is essential for maintaining the habitable climate on our planet – meaning it can sustain life. A great 3-minute video about how greenhouse gases work can be watched here.
How does the effect work?
The greenhouse effect works by allowing sunlight (shortwave radiation) to enter the atmosphere and warm the Earth's surface. The Earth then emits this energy in the form of infrared radiation (longwave radiation). Greenhouse gases absorb and re-radiate this infrared radiation, trapping heat in the atmosphere and warming the planet. The more greenhouse gases we have in the atmosphere, the more re-radiation will occur, and the warmer the Earth gets.
Historical Context and Current Trends
Over the past 800,000 years, atmospheric CO₂ levels have varied naturally, but they have risen sharply in the past 150 years due to human activities such as burning fossil fuels, deforestation, and industrial processes. These have significantly increased the levels of CO₂, CH4 and N20 in the atmosphere and correlates with the industrial revolution and the subsequent increase in energy consumption and industrial output.
This chart is showing atmospheric CO2 concentrations, parts per million. Source NASA. It highlights the natural fluctuations and the significant rise in the past century and a half.
Conclusion
The Greenhouse Gas Effect is essential for life on Earth. However, the way we as humans alter the composition of our atmosphere has changed the way this effect works and poses a real threat to all living creatures unless we act. One of the first steps we can take as individuals and businesses is to understand how much CO₂ we are creating, then we can identify carbon hotspots and make effective reductions. Measuring our carbon footprint is crucial, and that is something MyImprint can help you with. Because what gets measured, gets managed.
Comentários