Jakarta –
Satellite measurements in Antarctica have again detected a giant hole in the ozone layer. The hole in the area that scientists call the “ozone depletion region” measures 26 million square kilometers, or about three times the size of Brazil.
The European Space Agency’s Copernicus Sentinel-5P satellite made the recording on September 16, 2023, as part of the European Union’s environmental monitoring program.
Claus Zehner, Copernicus Sentinel-5P mission manager, told DW this was one of the largest ozone holes they had ever seen.
“The satellite measures trace gases in the atmosphere to monitor ozone and climate. This shows that this year’s ozone hole started earlier than usual, and is large in size,” Zehner said.
Experts say the ozone hole is unlikely to increase warming on the surface of Antarctica. “This is not a problem for climate change,” Zehner said.
The size of the ozone hole fluctuates every year
The ozone layer is a trace gas in the stratosphere, one of the four layers of the Earth’s atmosphere. This layer functions as a protective gas that absorbs ultraviolet (UV) radiation, protecting humans and the Earth’s ecosystem from high exposure to UV rays.
Most skin cancers are caused by exposure to high levels of UV radiation. So, anything that protects us from UV rays will help reduce the number of cancer sufferers.
The size of the ozone hole in Antarctica fluctuates every year. The ozone hole usually opens every year in August and closes again in November or December.
Zehner said that the ozone hole opened because the earth’s rotation caused a special kind of wind to occur on the closed land of Antarctica.
“The wind creates a mini-climate, creating a shield over Antarctica that prevents it from mixing with the surrounding air. When the wind dies down, the hole closes,” Zehner said.
What causes this giant ozone hole?
Scientists say this year’s large ozone hole was likely caused by the volcanic eruption at Hunga Tonga in Tonga during December 2022 to January 2023.
“Under normal conditions, the gas released from volcanic eruptions remains below the stratosphere, but this eruption caused a lot of water vapor to be released into the stratosphere,” said Zehner.
Water causes changes to the ozone layer through chemical reactions and changes its heating rate. This water vapor also contains other elements that can damage ozone such as bromine and iodine.
“There’s not much evidence that this ozone hole is caused by humans,” Zehner said.
The ozone hole could also be caused by human activity
The large ozone hole in Antarctica this year is likely not caused by human activity. However, scientists realized that human activities had created a huge ozone hole in the 1970s.
Ground and satellite measurements have detected the holes, which are caused by the widespread use of chemicals called chlorofluorocarbons.
“The cause of ozone depletion is not the aerosol content in aerosol cans, but the propellant that we use as a gas to propel the solution inside. This gas propellant contains chlorine, which is released deep in the stratosphere and erodes ozone,” said Jim Haywood, professor of atmospheric sciences at the University of Exeter in England.
The world quickly took action after scientists raised concerns over the expanding ozone hole. In 1987, the Montreal Protocol was established to protect the ozone layer by phasing out the production of these dangerous substances.
The good news is: this protocol is effective. The ozone hole has been getting smaller in the decades since the production of ozone-depleting gas emissions was controlled.
What effect does the ozone hole have on Earth’s climate?
Scientists agree that ozone depletion is not the main cause of global climate change.
However, Professor Haywood said there were signs that rising global temperatures could have an impact on the ozone hole. “Our mitigation of the ozone hole has been going well since the 1980s. But in 2020 we were surprised when the 2020 ozone hole turned out to be very deep and long-lasting,” he told DW.
The same thing will happen in 2021. Research shows that the main cause of the large ozone hole in 2020 was due to forest fires in Australia in the same year.
Haywood said as the climate crisis continues, and the earth continues to warm, fires are becoming more frequent and having a more devastating impact around the world.
“This year has been a very bad year for forest fires in the Northern Hemisphere. If this continues, there will be more smoke going into the stratosphere, and we will probably see even more ozone depletion,” according to Haywood.
It is still not very clear what impact the ozone hole will have on Earth’s climate. Some data shows that the ozone hole actually contributes to the cooling effect of temperatures, because it can reduce the effects of greenhouse gases.
But Haywood said there is evidence that the ozone hole influences the course of the seasons.
“If ozone depletion occurs, the hole will take longer to recover. This means the polar vortex will be longer, so winter will last a little longer,” he concluded.
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2023-10-10 05:03:11
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