Close X
Saturday, November 2, 2024
ADVT 
Health

Antarctic ice began melting earlier than thought

Darpan News Desk IANS, 29 May, 2014 02:04 PM
    Coming on the heels of recent studies that suggest destabilisation of part of the West Antarctic ice sheet has begun, a study shows that the Antarctic ice sheet began melting about 5,000 years earlier than previously thought - at the end of last ice age.
     
    The shrinkage of the vast ice sheet accelerated during eight distinct episodes, causing rapid sea level rise, it added.
     
    “Conventional thinking is that the Antarctic ice sheet has been relatively stable since the last ice age, that it began to melt relatively late and that its decline was slow and steady until it reached its present size,” said lead author Michael Weber, a scientist from University of Cologne in Germany.
     
    “The sediment record suggests a different pattern - one that is more episodic and suggests that parts of the ice sheet repeatedly became unstable during the last deglaciation,” Weber added.
     
    The researchers examined two sediment cores from the Scotia Sea between Antarctica and South America that contained "iceberg-rafted debris”.
     
    Periods of rapid increases in iceberg-rafted debris suggest that more icebergs were being released by the Antarctic ice sheet.
     
    The researchers discovered increased amounts of debris during eight separate episodes beginning as early as 20,000 years ago, and continuing until 9,000 years ago.
     
    The melting of the Antarctic Ice Sheet was not thought to have started, however, until 14,000 years ago.
     
    The research also provides the first solid evidence that the Antarctic ice sheet contributed to what is known as meltwater pulse 1A - a period of very rapid sea level rise that began some 14,500 years ago.
     
    "During that time, the sea level on a global basis rose about 50 feet in just 350 years - or about 20 times faster than sea level rise over the last century," noted Peter Clark, an Oregon State University paleoclimatologist.
     
    “We do not yet know what triggered these eight episodes or pulses, but it appears that once the melting of the ice sheet began it was amplified by physical processes,” he added.
     
    Some 9,000 years ago, the episodic pulses of melting stopped, the researchers said.
     
    Perhaps the sheet ran out of ice that was vulnerable to the physical changes that were taking place.
     
    “However, our new results suggest that the Antarctic Ice Sheet is more unstable than previously considered,” they emphasised in the study published in the journal Nature.

    MORE Health ARTICLES

    How your immune system can fight back cancer

    How your immune system can fight back cancer
    In a groundbreaking treatment, researchers at the National Cancer Institute in the US have harnessed a female patient's own immune system to fight cancer.

    How your immune system can fight back cancer

    Certainty on sea levels rise by 2030: Scientists

    Certainty on sea levels rise by 2030: Scientists
    The burning question whether sea level rise is accelerating can only be answered with a degree of certainty by 2030, an international team of scientists has claimed.

    Certainty on sea levels rise by 2030: Scientists

    Genes decide if medicine will work for you or not

    Genes decide if medicine will work for you or not
    Ever wondered why a particular medicine is effective for certain people but not for others? That is largely decided by genes, research reveals.

    Genes decide if medicine will work for you or not

    Ancient Egyptians were largely veggies

    Ancient Egyptians were largely veggies
    What exactly did people living along the banks of the Nile river thousands of years ago exactly eat? New research has unlocked the secret: Like most modern people, their diet was wheat and barley-based.

    Ancient Egyptians were largely veggies

    Meal shake: A drinkable meal on the go

    Meal shake: A drinkable meal on the go
    What if you can drink your meal instead of eating it? You would be left with no excuse to miss it, however busy you may be.

    Meal shake: A drinkable meal on the go

    How much sleep parents lose over a child? Eight years

    How much sleep parents lose over a child? Eight years
    Believe it or not, if you are a parent you will have over eight years worth of sleepless nights by the time your child turns 30, a British study has revealed.

    How much sleep parents lose over a child? Eight years