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NASA: Earth’s Ozone Hole Shrinks to Smallest Since 1988

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NASA: Earth's Ozone Hole Shrinks to Smallest Since 1988 (VOA)
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Washington: The ozone hole over Antarctica shrank to its smallest peak since 1988, NASA said Thursday. The huge hole in Earth’s protective ozone layer reached its maximum this year in September, and this year NASA said it was 7.6 million square miles (19.6 million square kilometers). The hole size shrinks after mid-September.

This year’s maximum hole is more than twice as big as the United States, but it’s 1.3 million square miles smaller than last year and 3.3 million square miles smaller than 2015.

FILE - A false-color view of total ozone over the Antarctic pole is seen in this NASA handout image released Oct. 24, 2012. The purple and blue colors are where there is the least ozone. The average area covered by the Antarctic ozone hole in that year was the second smallest in two decades, at 8.2 million square miles; in September 2017, it was 7.6 million square miles.

[ FILE – A false-color view of total ozone over the Antarctic pole is seen in this NASA handout image released Oct. 24, 2012. The purple and blue colors are where there is the least ozone. The average area covered by the Antarctic ozone hole in that year was the second smallest in two decades, at 8.2 million square miles; in September 2017, it was 7.6 million square miles ].

Paul Newman, chief Earth scientist at NASA’s Goddard Space Flight Center, said stormy conditions in the upper atmosphere warmed the air and kept the chemicals chlorine and bromine from eating ozone. He said scientists haven’t quite figured out why some years are stormier — and have smaller ozone holes — than others.

“It’s really small this year. That’s a good thing,” Newman said.

Newman said this year’s drop is mostly natural but is on top of a trend of smaller steady improvements likely from the banning of ozone-eating chemicals in a 1987 international treaty. The ozone hole hit its highest in 2000 at 11.5 million square miles (29.86 million square kilometers).

Ozone is a colorless combination of three oxygen atoms. High in the atmosphere, about 7 to 25 miles (11 to 40 kilometers) above the Earth, ozone shields Earth from ultraviolet rays that cause skin cancer, crop damage and other problems.

Scientists at the United Nations a few years ago determined that without the 1987 treaty, by 2030 there would have been an extra 2 million skin cancer cases. They said that overall, the ozone layer is beginning to recover because of the phase-out of chemicals used in refrigerants and aerosol cans. (VOA)

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NASA: No contact Made With Storm-Hit Mars Rover, Till Now

Because Opportunity runs on solar energy, scientists had to suspend science activities to preserve the rover's batteries.

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NASA said no response has been received from the rover as of July 18. Flickr

 NASA is yet to make contact with its Mars Opportunity Rover ever since a massive storm started on the Red Planet in June.

Based on the longevity of a 2001 global storm, NASA scientists estimate it may be September before the haze has cleared enough for Opportunity to power up and call home, the US space agency said this week.

Scientists first observed a smaller-scale dust storm on May 30. By June 20, it had gone global.

For the Opportunity rover, that meant a sudden drop in visibility from a clear, sunny day to that of an overcast one.

Because Opportunity runs on solar energy, scientists had to suspend science activities to preserve the rover’s batteries.

NASA said no response has been received from the rover as of July 18.

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The nearly 15-year-old rover is not out of the woods yet as it could take weeks, or even months, for the dust to start settling. Pixabay

Luckily, all that dust acts as an atmospheric insulator, keeping nighttime temperatures from dropping down to lower than what Opportunity can handle.

But the nearly 15-year-old rover is not out of the woods yet as it could take weeks, or even months, for the dust to start settling.

When the skies begin to clear, Opportunity’s solar panels may be covered by a fine film of dust. That could delay a recovery of the rover as it gathers energy to recharge its batteries. A gust of wind would help, but is not a requirement for a full recovery, NASA said.

While the Opportunity team waits in earnest to hear from the rover, scientists on other Mars missions have gotten a rare chance to study this storm.

Also Read-Survival Of Mars Rover Is Under Threat Due To A sandstorm

The Mars Reconnaissance Orbiter (MRO), Mars Odyssey, and Mars Atmosphere and Volatile EvolutioN (MAVEN) orbiters are all tailoring their observations of the Red Planet to study this global storm and learn more about Mars’ weather patterns.

Meanwhile, the Curiosity rover is studying the dust storm from the Martian surface, the US space agency added. (IANS)

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