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Sudden ice loss in Antarctica affecting Earth’s gravitational field

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By NewsGram Staff Writer

In a recent research, a team of scientists have published that Antarctica is experiencing a sudden increase in ice loss which is causing small changes in the gravitational field of the Earth. Since 2009, multiple glaciers along a vast coastal expanse have disappeared in the ocean.

“To date, the glaciers added roughly 300 cubic km of water to the ocean. That’s the equivalent of the volume of nearly 350,000 Empire State buildings combined,” a lead study author Bert Wouters at the University of Bristol said.

“The fact that so many glaciers in such a large region suddenly started to lose ice came as a surprise to us. It shows a very fast response of the ice sheet: in just a few years the dynamic regime completely shifted”, added Bert.

The changes were detected by the CryoSat-2 satellite, operated by the European Space Agency.

The ice loss in the region is so large that it is causing small changes in the gravity field of the Earth. Such a change can be detected by another satellite mission, the Gravity Recovery and Climate Experiment (GRACE).

In the last two decades, the ice shelves in the region have lost almost one-fifth of their thickness, thereby reducing the resisting force on the glaciers.

“To pinpoint the cause of the changes, more data need to be collected. A detailed knowledge of the geometry of the local ice shelves, the ocean floor topography, ice sheet thickness and glacier flow speeds are crucial to tell how much longer the thinning will continue,” Wouters concluded.

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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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Delayed Onset and Early Departure of Winter Reflect Changing Climate, Scientists Say

Shorter winters and hotter temperatures are expected to lead to rising seas that cause worse flooding during heavy storms.

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Sun rays spill through a gap between the clouds and the White Mountains as the skies begin to clear above Bartlett, New Hampshire, Friday, Sept. 22, 2017. The first weekend of autumn is expected to be unusually warm with temperatures expected to reach the upper 80s. (AP Photo/Robert F. Bukaty)

Washington, October 29, 2017 : Winter is coming … later. And it’s leaving ever earlier.

Across the United States, the year’s first freeze has been arriving further and further into the calendar, according to more than a century of measurements from weather stations nationwide.

Scientists say it is yet another sign of the changing climate, and that it has good and bad consequences for the nation. There could be more fruits and vegetables — and also more allergies and pests.

“I’m happy about it,” said Karen Duncan of Streator, Illinois. Her flowers are in bloom because she’s had no frost this year yet, just as she had none last year at this time, either. On the other hand, she said just last week it was too hot and buggy to go out — in late October, near Chicago.

The trend of ever later first freezes appears to have started around 1980, according to an analysis by The Associated Press of data from 700 weather stations across the U.S. going back to 1895 compiled by Ken Kunkel, a meteorologist at the National Oceanic and Atmospheric Administration’s National Centers for Environmental Information.

To look for nationwide trends, Kunkel compared the first freeze from each of the 700 stations to the station’s average for the 20th century. Some parts of the country experience earlier or later freezes every year, but on average freezes are coming later.

Average first freeze

The average first freeze over the last 10 years, from 2007 to 2016, is a week later than the average from 1971 to 1980, which is before Kunkel said the trend became noticeable.

This year, about 40 percent of the Lower 48 states had a freeze as of October 23, compared with 65 percent in a normal year, according to Jeff Masters, meteorology director of the private service Weather Underground.

Duncan’s flowers should be dead by now. According to data from the weather station near her in Ottawa, Illinois, the average first freeze for the 20th century was October 15. The normal from 1981 to 2010 based on NOAA computer simulations was October 19. Since 2010, the average first freeze is on October 26. Last year, the first freeze in Ottawa came on Nov. 12.

Last year was “way off the charts” nationwide, Kunkel said. The average first freeze was two weeks later than the 20th century average, and the last frost of spring was nine days earlier than normal.

ALSO READ Hottest in History: India faced the Warmest Winter this year due to Global Warming, says Study

Overall the United States freeze season of 2016 was more than a month shorter than the freeze season of 1916. It was most extreme in the Pacific Northwest. Oregon’s freeze season was 61 days shorter than normal.

Global warming has helped push the first frosts later, Kunkel and other scientists said. Also at play, though, are natural short-term changes in air circulation patterns, but they, too, may be influenced by man-made climate change, they said.

This shrinking freeze season is what climate scientists have long predicted, said University of Oklahoma meteorology professor Jason Furtado.

Some plants suffer

A shorter freeze season means a longer growing season and less money spent on heat. But it also hurts some plants that require a certain amount of chill, such as Georgia peaches, said Theresa Crimmins, a University of Arizona ecologist. Crimmins is assistant director of the National Phenology Network. Phenology is the study of the seasons and how plants and animals adapt to timing changes.

Pests that attack trees and spread disease aren’t being killed off as early as they normally would be, Crimmins said.

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Morning dew covers berries in Bartlett, N.H., Sept. 18, 2017. Despite forecasts for brilliant foliage throughout the Northeast this year, longtime leaf watchers said the leaves this fall were dull and weeks behind schedule in their turn from green to the brilliant hues of autumn. VOA

In New England, many trees aren’t changing colors as vibrantly as they normally do or used to, because some take cues for when to turn from temperature, said Boston University biology professor Richard Primack.

Clusters of late-emerging monarch butterflies are being found far farther north than normal for this time of year, and are unlikely to survive their migration to Mexico.

Kevin Trenberth, a climate scientist at the National Center for Atmospheric Research, said natural variability, especially an El Nino, made last year exceptional for an early freeze, but “it represents the kind of conditions that will be more routine in a decade or two” because of man-made climate change.

“The long-term consequences are really negative,” said Primack, because shorter winters and hotter temperatures are also expected to lead to rising seas that cause worse flooding during heavy storms.

In suburban Boston, Primack and his wife are still eating lettuce, tomatoes and green beans from their garden. And they are getting fresh figs off their backyard tree almost daily.

“These fig trees should be asleep,” Primack said. (VOA)

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Researchers Claim The Existence Of Planet Nine

Researchers from an American University have laid evidences to prove the presence of Planet Nine

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Planet Nine
Kuiper Belt indicates the presence of Planet Nine
  • The science communities since a long time have been debating upon the existence of Planet Nine. 
  • Space highlights different shreds of evidence based on which scientists are stating the claim.

What Is Planet Nine?

Planet Nine is a hypothetical planet present in the far outer Solar System, whose mass is estimated to be 10 times more than the mass of Earth. The planet is said to be 20 times farther than the sun than Neptune is.

What Do Researchers Have To Say?

Dr Konstantin Batygin, a planetary astrophysicist at the California Institute of Technology, said that there were five different lines of observational evidence which pointed to the existence of Planet Nine. He stated that if this theory does not sound believable, then people would have to come up with the answers of the five pieces of evidence which could lead to further confusion.

Also Read: Five Students from Telangana Selected for the NASA Human Exploration Rover Challenge

Batygin in 2016 published a study examining the six known objects in the Kuiper Belt, a  circumstellar disc in the Solar System beyond the planets that extends from the orbit of Neptune towards interstellar space.

The study examines all the objects have elliptical orbits pointing in the same direction and are tilted the same way. These serve as evidence to the planet’s existence.

It is being said that the objects are tilted 30 degrees downward compared to the plane where the eight official planets circle the sun. Researchers also made use of computer simulations of the solar system including the Planet Nine and to demonstrate that there should be more objects tilted a whopping 90 degrees to solar plane. It was revealed that five such objects, which fit these parameters were already known.

The study led to the birth of two more ideas. Researchers said that this planet could have tilted the planets of the solar system during the last 4.5 billion years.

Planet Nine’s existence could also tell the reason as to why Kuiper Belt objects orbit in the opposite direction as compared to other things in the solar system.

-Prepared by Megha Acharya of NewsGram.

(the story was originally published in PTI)