Ozone Layer Healing
More than 30 years after scientists first spotted a hole in the atmosphere’s protective ozone layer over the South Pole, they are seeing the “first fingerprints of healing,” researchers reported today (June 30).
Measurements of the ozone hole taken in September revealed the breach has shrunk by more than 1.5 million square miles (4 million square kilometers) — about half the area of the contiguous United States — since 2000.
The researchers attributed the ozone’s recovery to the continuing decline of atmospheric chlorine originating from chlorofluorocarbons (CFCs). These chemical compounds, once commonly used in aerosols, dry cleaning and refrigerators, were banned when nations around the world signed the Montreal Protocol in 1987 in an effort to repair the ozone hole.
The ozone layer, which extends from 2 to 19 miles (20 to 30 km) above Earth’s surface, protects the planet from the sun’s harmful ultraviolet rays. Thinning of ozone, which is a molecule made up of three oxygen atoms, can occur due to exposure to certain chemicals, like CFCs.
There is still a long road to recovery for the ozone hole, the researchers said. The molecules that deplete ozone have very long life spans, and the study scientists estimate it will still be decades before complete recovery.
The Window for Limiting Temperature rise to 1.5 C Has Closed
Barring some incredible new carbon capture technology, the window for limiting global warming to less than 1.5 degrees Celsius appears to have closed. That’s the stark conclusion of a report out in Nature today, which finds that the carbon reductions pledges penned into the Paris Agreement are ridiculously inadequate for keeping our climate within a safe and stable boundary.
In addition to concluding that “the window for limiting warming to below 1.5 degrees C with high probability and without temporarily exceeding that level already seems to have closed,” the study found that the pledges outlined in the Paris Agreement will likely see global temperatures rise 2.6 to 3.1 degrees Celsius by 2100. A 3 degree uptick in global temperatures could cause sea level to rise up to 20 feet over the next few centuries, displacing hundreds of millions.
Low-lying island nations, which area already drawing up relocation plans in preparation for the inevitable, fought long and hard to get the 1.5 target included in the Paris Agreement. Recently, marine biologists have also been raising their voices, reminding the public that coral reefs around the world will experience catastrophic collapse if we exceed this threshold.