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Forbidden, ozone-depleting chemicals are still being produced somewhere, scientists say



Someone seems to be producing a banned ozone depleting chemical that interferes with the recovery of the earth-damaged ozone layer, according to a recent study led by scientists from the National Oceanic and Atmospheric Administration.

The illegal emissions are thought to come from somewhere in East Asia, but otherwise nothing is known about the offender. It's a scientific thriller – or rather, one who does it .

"I think it's the most surprising thing I've measured in my 27 years, in which traces of gases in the atmosphere," Stephen Montzka, lead author of the study, tells NPR.

In the study published on Wednesday in Nature the scientists say that the atmospheric content of trichlorofluoromethane or CFC-1

1 as a whole is still decreasing. But it does not go back as fast as it should.

"It seems that CFC-11 emissions have increased in recent years, which is quite surprising considering that production is phasing out," says Montzka.

CFCs or chlorofluorocarbons "were once widely used in the production of aerosol sprays, blowing and foaming agents, as solvents and as refrigerants," – said in a press release.

Chemicals damaged the ozone layer, which filters out harmful UV rays that can increase the risk of skin cancer (and, if left unchecked, would affect agriculture and ecosystems). In the late 1980s, the world agreed to phase out the use of chemicals, including CFC-11.

According to the researchers, there are still CFC-11 in insulation and older equipment. However, the new production should be discontinued from 2010. This means that the amount of CFC-11 in the atmosphere should decrease more and more every year, so that the ozone layer can fill up.

Data from a NOAA study show these emissions of CFC-11 – as calculated using two different models – rose after 2012, although production is reported to be phasing out. Scientists say it is not clear why emissions remained stable after 2002, but "new production" probably explains the increase after 2012. (Figure 2, Panel a, Montzka et al., 2018, NOAA)

But the rate the reduction is slowdown that does not meet expectations. The scientists analyzed measurements from 12 different sites and concluded that after 2012, two years after the production of the chemical, CFC-11 emissions increased to zero.

Their data suggest that the source is north of the equator and probably east of Asia.

Montzka says it's possible that production is random, but it could also be the result of a deliberate violation of the Montreal Protocol.

Either way, it's bad news for the ozone layer. CFC-11 is the second most abundant ozone-depleting substance in the atmosphere, and ozone depletion is essential for ozone depletion.

The next step for atmospheric researchers is to try to limit the source of emissions. With the help of scientists from across East Asia, Montzka says:

The United Nations Ozone Secretariat says it is "critical" to "cause these emissions to identify and take the necessary measures ".

"It is important to note these results also underline the effectiveness of the Montreal Protocol, its institutions and mechanisms, with science at the center," says the Secretariat. "As long as the scientists remain vigilant, new productions or emissions of ozone-damaging chemicals will not go unnoticed."

However, the problem is not the same as a correction.

The Montreal Protocol was a remarkably effective agreement. But David Victor, a professor of international relations at the University of California, San Diego, says there is no easy way for the international community to act against them.

If a country deliberately violates the protocol, "there is an enforcement mechanism, but it has no teeth," says Victor NPR. "They can file reports, trade sanctions threaten … At the end of the day, when a country has truly committed itself to violating an agreement, they can probably do so."

Another likely scenario is that a government wants to impose the ban, but its enforcement capacity is lacking to crack illegal production. That was a problem with the Montreal Protocol before.

"Since CFCs have been regulated, the value of them on the black market has increased," explains Victor. "It's not much different than running a drug business."

In this case, other countries can offer technical assistance, but "it is very difficult for an outside country … and to participate in enforcement measures," Victor says.

Copyright NPR 2018.


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