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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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Facts About Lonar Lake That Will Leave You Awestruck

Lake is said to be one of Maharashtra’s best-kept secrets as not many people know about this magnificent phenomenon

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The Lonar lake is one of its kinds, not only in India but on the planet, which kept it pretty well-preserved for thousands of years. Wikimedia Commons
The Lonar lake is one of its kinds, not only in India but on the planet, which kept it pretty well-preserved for thousands of years. Wikimedia Commons
  • The Lonar Lake is located at Lonar in Buldhana district, Maharashtra, India
  • The lake was created by a meteor impact during the Pleistocene Epoch
  • Lonar Lake is a notified National Geo-heritage Monument saline soda lake and lies in a basalt impact structure

The Mother Nature is full of natural wonders, from hills and valleys to rivers and oceans, from the hundreds and thousands of species of plants and animals to the wind, breeze and sky, nature is what makes this world worth living in.

The Lonar Lake that is saline and alkaline at the same time- this unique combination makes the lake pretty unique. It is located at Lonar in Buldhana district, Maharashtra, India. That is something that you don’t really see on a fairly regular basis and has been subject to scientific studies for a very long time. To know more about it, many geologists, archaeologists, naturalists and astronomers have published studies of various aspects of this Lonar Crater Lake ecosystem. The lake is also known as ‘Lonar Sarovar.’

Also Read: Facts That Will Amaze You About Kerala’s Jatayu National Park

Lonar Lake Mystery

This peculiar lake is one of its kinds, not only in India but on the planet, which kept it pretty well-preserved for thousands of years. It was created by a meteor impact during the Pleistocene Epoch and it is the only known hypervelocity impact crater in basaltic rock anywhere on Earth. Lonar Lake is said to be one of Maharashtra’s best-kept secrets as not many people know about this magnificent phenomenon.

The Lonar Lake was formed when a blazing ball of fire crashed into the earth at an estimated speed of 90,000 km per hour. Wikimedia Commons
The Lonar Lake was formed when a blazing ball of fire crashed into the earth at an estimated speed of 90,000 km per hour. Wikimedia Commons

The Lonar Lake mystery still perplexes many. The estimated age of the lake is said to be a topic of contention. Generally, the Lonar Lake is believed to be 50,000 incredibly years old but according to some studies, gives an age of 570,000 years. Geological Society of India has conducted extensive studies of the site. Later in 2007, the biological nitrogen fixation nature of Lonar Lake was also discovered.

The circular depression bears a saline water lake in its central portion. It was formed when a blazing ball of fire crashed into the earth at an estimated speed of 90,000 km per hour. This hit resulted into eruption and spewing molten rock to create a magnificent crest on the rim. With the gentle passage of time, green cover took over in the surrounding of the lake and a perennial stream transformed the crater into a tranquil, emerald green lake.

Also Read: Nalanda University: 5 Lesser-Known Facts About The Ancient University

Lonar Lake Tourism

The land-locked water body is an exceptional ‘bowl of biodiversity’ and a wildlife sanctuary with a unique ecology that is vastly different from the surrounding flat landscape and supports micro-organisms rarely found elsewhere on earth. At first, it was believed that the lake was of volcanic origins but further studies proved that the lake was sitting in a crater formed by extraterrestrial impact. The presence of maskelynite and the planar deformation features are not part of volcanic origins. Thus, it leads to the abandoning of volcanic origin theory.

The land-locked water body is an exceptional ‘bowl of biodiversity’ and a wildlife sanctuary. Wikimedia Commons
The land-locked water body is an exceptional ‘bowl of biodiversity’ and a wildlife sanctuary. Wikimedia Commons

Here 10 facts about Lonar lake, which will help you to dwell more of its origins and unique features.

  1. Lonar Lake is a notified National Geo-heritage Monument saline soda lake and lies in a basalt impact structure
  2. The lake has a diameter of 1.2 kilometres (3,900 ft) and is about 137 metres (449 ft) below the crater rim.
  3. The crater’s oval shape indicates that the asteroid or the comet had hit India’s Deccan Traps basaltic formation as an angle of 35 degrees to 40 degrees.
  4. The lake is surrounded by eight ancient temples dating all the way back to the 6th century to the 12th century from the Chalukya and the Yadava period. Many of the temples here have perplexing carvings on the walls that resemble the world-famous group of temples in Khajuraho. Unfortunately, apart from Kamalaja Devi Temple, all others are in ruins.
  5. Even the lake is mentioned in historic tales from the Ashoka Empire, the Chalukya Dynasty, and all the way to the Mughals and Nizams.
  6. It was in the early 19th century in 1823, when the first time a European visited the lake, British officer, JE Alexander.
  7. According to NASA, the crater’s volcanic basalt makes Lonar a well similar to that of impact craters on the surface of the Moon. Moreover, the recently discovered bacterial strain on the lake’s crater site resembles the one found on Mars.
  8. Due to high amounts of soda in it, it makes it impossible for any type of vegetation to grow here.
  9. Still, the lake is considered as the youngest and best-preserved impact crater formed in basalt rock and is the only of its kind on earth.
  10. To measure the age of lake, there were different methods used. One was thermoluminescence analysis which revealed that the age of the lake to be 52,000 years old with a spread of 6000 years correction on either side. That simply puts the age of the Lonar Crater Lake to be anywhere between 46,000 years and 58,000 years. On the other hand, the second method was Argon-Argon dating which says that the crater was formed some 570,000 years ago with a spread of 47,000 years correction on either side.
  11. The Lonar Lake has been mentioned in ‘Skanda Purana’ which is the longest of the 18 Mahapuranas that gives insights on the various pilgrim centres in the country.
  12. The crater impact also makes it a place for maskelynite. Maskelynite is a kind of naturally occurring glass that is only formed by extremely high-velocity impacts.
    According to NASA, the crater’s volcanic basalt makes Lonar a well similar to that of impact craters on the surface of the Moon. Wikimedia Commons
    According to NASA, the crater’s volcanic basalt makes Lonar a well similar to that of impact craters on the surface of the Moon. Wikimedia Commons

    The visitors have to trek through the dense forest to reach this marvellous location. One can experience wide varieties of flora and fauna over here. Birds like the Black-winged Stilts, Brahminy ducks and Bay Weavers among others can be spotted here regularly. Even Bats, Langur, Gazelles and Chikaras makes a visit here regularly.

    A series of a low hill around the crater basin sits with an 8 kilometres circumference on the top. The side area of the basin has a steep rise of 75 degrees and is covered with multiple rings of trees. Each ring of the tree is made up of a specific species of tree. For instance, the first and outermost ring is of date palms.