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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)

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’S Twins Study Claims, Long-term Spaceflight Not Linked to Major Health Risks

"It's almost as if the body's on high alert," said Christopher Mason, Associate Professor at Weill Cornell Medicine.

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Spending nearly a year in orbit increased NASA astronaut Scott Kelly's immune system response, as if, at the cellular level, his body felt under attack as compared to his Earth-bound twin brother, the Washington Post reported on Friday. Pixabay

While it was previously thought that long duration spaceflight can affect the human body, even at the molecular level, new results from NASAs “Twins Study” has showed that there are no major warning signs and no reason to think humans cannot survive a two-and-a-half-year round-trip journey to Mars.

As part of the “Twins Study”, NASA astronaut Scott Kelly spent a year in space while Mark, his identical twin, stayed on Earth as a control subject to look at the effects of space travel on the human body.

Spending nearly a year in orbit increased NASA astronaut Scott Kelly’s immune system response, as if, at the cellular level, his body felt under attack as compared to his Earth-bound twin brother, the Washington Post reported on Friday.

NASA
According to report, the biggest concern is radiation as such a mission would expose astronauts to levels of radiation greater than permitted under current guidelines. That would not necessarily prevent a mission, but it remains a concern. Pixabay

These comparisons, however, has not raised any red flags about long-term spaceflight on the International Space Station (ISS), NASA officials were quoted as saying at the annual meeting of the American Association for the Advancement of Science here.

“It’s almost as if the body’s on high alert,” said Christopher Mason, Associate Professor at Weill Cornell Medicine.

The space sojourn also changed the activity of some of his genes.

“It’s mostly really good news,” Mason said, adding, “the body has extraordinary plasticity and adaptation to being in zero gravity, at least for a year”.

NASA
“It’s almost as if the body’s on high alert,” said Christopher Mason, Associate Professor at Weill Cornell Medicine. Pixabay

According to Craig Kundrot, Director of NASA’s space life and physical sciences division, so far the space agency’s research found nothing that would make a Mars mission impossible.

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According to report, the biggest concern is radiation as such a mission would expose astronauts to levels of radiation greater than permitted under current guidelines. That would not necessarily prevent a mission, but it remains a concern.

However, Kundrot cautioned that the twin study has only two people as samples. “We don’t regard any of this as conclusive, but on the whole it’s encouraging,” he said, adding, “there are no new major warning signs”. (IANS)