At first glance, this might sound like good news. But at the same time, he notes that very few CFCs have been produced illegally in recent years.
Currently, there should be much lower concentrations of CFCs – or CFCs – in our atmosphere than there is. Researchers concluded this in a new study. They found that ozone-destroying CFCs lingered in the atmosphere for much less time than previously thought. The fact that concentrations are still relatively high, according to her, indicates that very few CFCs have been illegally produced in recent years.
CFCs are long life chemical compounds that are widely used in the production of refrigerants, aerosols, chemical solvents and building insulation. When it’s taken out, chemicals can rise into the stratosphere. Here they are broken down by the sun’s ultraviolet rays, releasing chlorine atoms. These atoms destroy ozone molecules. This is bad news, because ozone protects life on our planet by absorbing potentially harmful ultraviolet rays. For example, ultraviolet rays can cause skin cancer, cataracts, and harm plants. To put an end to CFCs, the Montreal Protocol on Substances that Deplete the Ozone Layer (abbreviation of the Montreal Protocol) was established. Thus, governments promised to reduce the production of substances that deplete the ozone layer. Meanwhile, the so-called “hole in the ozone layer” is already recovering.
In 2010, the use of CFCs was phased out. And that paid off. In recent years, it has become apparent that the hole in the ozone layer has slowly started to stabilize and even shrink. For example, between September 2000 and September 2015, the gap narrowed by more than 4.4 million square kilometers. However, in 2018, the volume increased slightly again, which could indicate that not everyone is adhering to the Montreal Protocol properly.
In the new study, the researchers decided to put things in order. Because even though the use of CFCs is now banned, there are still old devices in circulation – made before the chemicals were banned – that are still pumping CFCs into the atmosphere. In a previous study, researchers calculated how many CFCs these devices release into the atmosphere. In the new study, they decided to refine existing estimates of life span of CFCs. Together, this provides more information about how many CFCs there must be in our atmosphere and whether that corresponds to reality.
The researchers looked at the lifetimes of several CFCs: CFCs 11, 12, and 113. The team found the average life span to be 49 years, 85 years, and 80 years, respectively. Previously, the age was estimated at 52, 100 and 85 years old. This means that ozone-destroying CFCs remain in the atmosphere for a shorter period of time than expected.
This may seem like good news at first glance. But at the same time, he notes that very few CFCs have been produced illegally in recent years. The observed concentration of CFCs in the atmosphere cannot be completely traced back to old equipment. So the results mean that not everyone has adhered to the agreements reached in the Montreal Protocol. The results indicate the potential for new illegal emissions of CFC-11, CFC-12 and CFC-113 in recent years.
More than expected
The results are consistent with the observation that the size of the hole in the ozone layer increased slightly again in 2018. But the researchers believe that more polluting CFCs were pumped into the air than previously expected. Not only does it appear that more CFCs have been released, it now also appears that CFC-12 and CFC-113 ended up in the air. This can be easily explained by the way. For example, CFC-12 is a by-product in manufacturing processes that emit CFC-11. For CFC-113, the use of the chemical is allowed under certain conditions. But the team estimated that the unexpected emissions of CFC-113 are about 10 times higher than what the Montreal Protocol allows. In total, the researchers estimate that these new emissions of CFCs are in line with the UK’s total annual greenhouse gas emissions.
How Q How
Researchers do not know exactly who is emitting these illegal gases. The team was able to track half of the peak observed in CFC-11 emissions between 2014 and 2016 to eastern China. However, scientists have since noticed a decrease in emissions from this area, indicating that illegal production there has stopped. The source of the remaining unexpected releases remains unknown.
Although the emissions of these three gases are much lower than they have ever been before, they are still worrying results. CFCs are very powerful greenhouse gases that destroy the ozone layer, so that all emissions have important impacts on the health of our planet. “We are currently facing a climate crisis,” said study leader Megan Lickley. “Every source of emissions that we can reduce has a huge impact. So if we focus now on CFCs, we will reduce a large part of the contribution to climate change.”
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