The ozone hole is slowly on the mend, according to New Zealand scientists studying the atmosphere over Antarctica.
The data comes from a tiny observation lab that has been running at Scott Base, New Zealand's outpost on the frozen continent, for the past 30 years.
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Support workers like Antarctica New Zealand's Hue Tran drive up to the base every sunny day, exposing the instruments to the sun, and sending data back to Wellington to be analysed.
The base is home to several atmospheric studies and research there into the ozone hole over Antarctica has become one of the most long-running and authoritative research projects in the world.
Ozone absorbs ultraviolet light emitted by the sun, protecting humans, plants and animals from radiation that can cause things like skin cancer and sunburn. The ozone hole is known to cause skin cancer and sunburn.
The remote research centre means scientists like Richard Querel, based at Lauder in Otago, can make their assessments without leaving home.
It shows that slowly over time the ozone hole is getting smaller thanks to the international ban on the chemical CFC, which is used in refrigerants, and known to destroy ozone.
"You're getting this kind of slow ramp-down and yes you see this healing, this recovery that's being talked about. In the last few years, it looks like we're kind of at this turning point that recovery's actually beginning," he says.
The scientist has a sister machine set up in Lauder and says while there are improvements overall, there are some irregularities in the data, indicating that some countries have started making CFCs again in violation of international law.
"There are some studies mid-2018 that pointed to South East Asia as a possible source for some of these and so that might be in foam manufacturing, or they were thinking maybe it was refrigeration recycling that possibly wasn't being done to spec.
"A lot of it still exists, but it's almost just waiting because it's in a fire extinguisher, or it's in an old refrigerator that's at a landfill. And so some of these are going to come out as these things get processed again."
But long term studies mean old equipment and back on the ice, the machines making it all possible are straight out another era.
The ozone machine, known as a Dobson, was built before the World Wars in the early 1930s.
It was brought to the ice in 1988 and has been measuring ozone ever since, splitting the light with a prism and running it through a complicated system of mirrors.
It's managed in Antarctica by technical support worker Ms Tran, who says the best readings are gathered on sunny, cloudless days.
"What we do here is so important, especially the Dobson, because it measures the ozone and the ozone is what protects from the radiation from the sun," she says.
"You get to save the environment and that's the best feeling ever."
Good old fashioned Kiwi ingenuity, helping a tiny lab in Antarctica to lead the world in atmospheric science.
Newshub.