Earth's ozone hole shrinks to smallest size since 1988
- 7 years ago
ANTARCTICA — NASA announced on Thursday that the hole in the Earth's ozone is the smallest it's been for the last 29 years, though not because toxic emissions have gone down.
According to NASA, the ozone hole that formed over Antarctica this year measured 7.6 million square miles at its maximum peak on September 11, and is as small as it has been since 1988.
Ozone molecules shield the Earth from the sun's UV radiation, but are being depleted by man-made chemicals like bromine and chlorine that are released into the atmosphere.
The hole in the ozone has been growing larger over the years, measuring more than 11 million square miles at its highest.
Ozone deteriorates more quickly in colder temperatures, and in the presence of polar stratospheric clouds that encourage ozone-eating chemical reactions.
This year's weak depletion is largely due to stormy conditions in the upper atmosphere, which warmed temperatures and kept toxic chemicals from destroying the ozone.
While the small ozone hole resulted from mostly natural causes, steady improvements such as the banning of ozone-eating chemicals in a 1987 international treaty may have also contributed.
According to NASA, the ozone hole that formed over Antarctica this year measured 7.6 million square miles at its maximum peak on September 11, and is as small as it has been since 1988.
Ozone molecules shield the Earth from the sun's UV radiation, but are being depleted by man-made chemicals like bromine and chlorine that are released into the atmosphere.
The hole in the ozone has been growing larger over the years, measuring more than 11 million square miles at its highest.
Ozone deteriorates more quickly in colder temperatures, and in the presence of polar stratospheric clouds that encourage ozone-eating chemical reactions.
This year's weak depletion is largely due to stormy conditions in the upper atmosphere, which warmed temperatures and kept toxic chemicals from destroying the ozone.
While the small ozone hole resulted from mostly natural causes, steady improvements such as the banning of ozone-eating chemicals in a 1987 international treaty may have also contributed.