• The Arctic Ocean could be ice-free sooner than what most of the scientific studies have predicted so far.
  • The problem is, microwave measurements from satellites don’t penetrate the salty snow very well, so the satellite is not measuring the proper sea ice freeboard and the satellite readings overestimate the thickness of the ice.
  • All this while, all the scientific estimates on sea ice thickness and volume have been made based on the data provided by the European Space Agency’s CryoSat-2 (CS-2) satellite, considering that the satellite can accurately measure the sea ice freeboard, which is the ice we can see above sea level.
  • But that ice is covered in snow and the snow is salty close to where the sea ice surface is.
  • Prior to this study, it was believed that the volume of ice has been declining by 17 per cent every decade since 1979.
  • The new research shows that the rate of summer sea ice decline could be slightly faster.
  • Ice-free summers in the Arctic Ocean “would radically affect global weather patterns and dramatically increase the magnitude and frequency of storm events.
  • It would also dramatically alter the Arctic marine ecosystem, with the added sunlight affecting the Arctic Ocean food web and melting the very ice bed on which animals like polar bears hunt.
  • In 2007, the Intergovernmental Panel on Climate Change (IPCC) had estimated that the Arctic will have an ice-free summer by the end of this century.
  • The sea ice extent is melting faster than at the same time of the year in 2012.
  • A team of researchers at Rutgers University has been harping on the concept of “Arctic amplification”.
  • It refers to the enhanced sensitivity of high latitudes to global warming.
  • Declining sea ice is one of the contributing factors to this phenomenon.
  • Extreme weather in Western Europe and large swathes of North America is attributed to Arctic amplification.
  • According to climatologists, changes in the jet streams, especially polar jet streams, are also linked to global warming.
  • Jet streams are ribbon of strong winds blowing high above in the atmosphere and exerting huge influence on weather patterns.
  • When the jet streams are warmer, their ups and downs become more extreme, bringing different weather to areas unaccustomed to climate variations.
  • They bring prolonged cold weather and snowfall to some places and extended summer with unusually hot conditions to others.
  • It explains the occurrence of massive snowstorms and bone-chilling cold on the east coast of the US and flooding in Britain.
  • With the warming of the Arctic and the loss of sea ice, scientists have observed that methane – a greenhouse gas – has started to bubble up to the surface at a precariously faster rate. Generally, it lies frozen on the sea bed.
  • One can’t be oblivious to another major concern: having less sea ice would lead to higher absorption of the sun’s energy as the surface of the earth gets darker.

Hard times for Arctic species

  • Species like polar bears, seals and walruses depend on sea ice cover to breed, hunt and rest.
  • The depleting sea ice causes malnutrition in them and their already declining population sees a further southward trend.
  • Dwindling sea ice cover has forced walruses to undertake a journey of hundreds of miles for food.
  • That’s precisely why tens of thousands of them are increasingly seen on beaches in Alaska and Russia.
  • They come here in search of rest.
  • The polar bears use sea ice in the Arctic as a hunting ground for seals.
  • However, they are experiencing weight loss in recent years as they have 30 less days every year to hunt on the ice.
  • Arctic regions of North America are losing their white patches and getting greener. Almost one-third of the land cover resembles landscapes found in warmer climes.
  • The images captured by Landsat satellites reveal a healthy growth of vegetation on the ground. ]
  • Rising temperatures in the Arctic has made the region conducive for plants to grow and led to the changes in the soils.
  • Grassy tundra is changing to shrubland and shrubs are growing bigger and denser.
  • The images suggested extensive greening in the tundra region of western Alaska, the tundra region of Quebec and Labrador and the northern coast of Canada.
  • Hence, the rapid loss of Arctic ice is not only spelling disaster for the Arctic species but also scripting a drastic shift in climatic patterns that the world is not yet ready to tackle.
  • For the Arctic, like the globe as a whole, 2016 has been exceptionally warm.
  • For much of the year, Arctic temperatures have been much higher than normal, and sea ice concentrations have been at record low levels.
  • The Arctic’s seasonal cycle means that the lowest sea ice concentrations occur in September each year. But while September 2012 had less ice than September 2016, this year the ice coverage has not increased as expected as we moved into the northern winter.
  • As a result, since late October, Arctic sea ice extent has been at record low levels for the time of year.