HFC-125, a synthetic gas, is in the spotlight. From space, recent measurements reveal a veritable explosion of its concentration in the atmosphere. This industrial compound could well amplify already critical climate problems.
Hydrofluorocarbons, which include HFC-125, were initially designed to replace CFCs, which are responsible for destroying the ozone layer. Although they have no impact on it, their effect on global warming is alarming. With a global warming potential 3,500 times greater than that of CO2 over 100 years, HFC-125 is a real heat trap.
Mainly used in air conditioning systems, refrigerators and fire extinguishers, HFC-125 is released into the atmosphere through industrial emissions. Its chemical stability makes it a persistent gas, which remains present for several decades.
For the first time, a team from the University of Waterloo, in collaboration with the Canadian Space Agency, measured its concentration from space. THE satellite ACE-FTS, in orbit since 2004, has provided precise data between 11 and 25 kilometers d’altitude.
The results are striking: in just two decades, HFC-125 levels have increased tenfold. This meteoric increase reflects the growing demand for cooling technologies, particularly in emerging countries where this equipment is becoming commonplace.
The climate impact of HFC-125 is not limited to its simple presence. By trapping infrared radiation, it accentuates the greenhouse effect and directly contributes to the increase in average global temperatures.
To control this trend, the international community adopted the Kigali Amendment to the Montreal Protocol. This text aims to gradually reduce the production and use of HFCs, by promoting more environmentally friendly alternatives.environment.
Researchers emphasize, however, that the effectiveness of these measures relies on their rapid and widespread application. Without immediate action, concentrations of HFC-125 will continue to rise, threatening to worsen an already fragile climate.
If the regulations bear fruit, as was the case with CFCs, scientists hope to observe a gradual decrease in this gas in the years to come. But time is running out to counter its effects and avoid irreversible climatic upheavals.
What is global warming potential (GWP)?
Global warming potential (GWP) is a measure of the impact of a greenhouse gas on global warming. It compares the capacity of a molecule to trap heat in the atmosphere relative to the carbon dioxide (CO₂), which serves as a reference. This value is calculated over a given period, often 20, 100 or 500 years. For example in the case of the study, a GWP of 3500 means that the gas retains 3500 times more heat than the same quantity of CO₂ over 100 years.
Gases with a high GWP, such as HFC-125, are therefore of particular concern. Their long lifespan amplifies their impact, as they persist in the atmosphere for decades or even centuries.
By taking into account the GWP, international regulations, such as the Kigali amendment, seek to reduce the use of these substances to limit their contribution to global warming.