Antarctic Peninsula Team of Polar Scientists Add New Dimension To Climate Change

Most people are unaware that the first sighting of the Antarctic Peninsula occurred in 1820, most likely during a Russian Imperial Navy expedition captained by Thaddeus von Bellinghausen. Since its discovery, the Peninsula has served the scientific community as a research platform toward gaining a better understanding of earth’s history and global climate change.  This week a team of polar scientists from Britain, Australia and France published results of their work, adding a new dimension to our understanding of Antarctic Peninsula climate change and the likely causes of the break-up of its ice shelves.

The first comprehensive reconstruction of a 15,000 year climate history from an ice core collected from James Ross Island in the Antarctic Peninsula region is reported this week in the journal Nature. The scientists reveal that the rapid warming of this region over the last 100 years has been unusual and came on top of a slower, natural climate warming that began around 600 years ago. These centuries of continual warming meant that by the time the unusual recent warming began, the Antarctic Peninsula ice shelves were already poised for the dramatic break-ups observed from the 1990’s onward.

The Antarctic Peninsula is one of the fastest warming places on Earth, the average temperatures from meteorological stations near James Ross Island having risen by nearly 2°C in the past 50 years.

Lead author Dr Robert Mulvaney OBE, from British Antarctic Survey (BAS) says, “This is a really interesting result. One of the key questions that scientists are attempting to answer is how much of the Earth’s recently observed warming is due to natural climate variation and how much can be attributed to human activity since the industrial revolution. The only way we can do this is by looking back through time when the Earth experienced ice ages and warm periods, and ice cores are a very good method for doing this.”

Dr Mulvaney continues, “We know that something unusual is happening in the Antarctic Peninsula. To find out more, we mounted a scientific expedition to collect an ice core from James Ross Island — on the northernmost tip of the Peninsula. Within the 364m long core are layers of snow that fell every year for the last 50,000 years. Sophisticated chemical analysis — at BAS and the NERC Isotope Geosciences Laboratory (part of British Geological Survey) — was used to re-create a temperature record over this period.

“For this study we looked in detail at the last 15,000 years — from the time when the Earth emerged from the last ice age and entered into the current warm period. What we see in the ice core temperature record is that the Antarctic Peninsula warmed by about 6°C as it emerged from the last ice age. By 11,000 years ago the temperature had risen to about 1.3°C warmer than today’s average and other research indicates that the Antarctic Peninsula ice sheet was shrinking at this time and some of the surrounding ice shelves retreated. The local climate then cooled in two stages, reaching a minimum about 600 years ago. The ice shelves on the northern Antarctic Peninsula expanded during this cooling. Approximately 600 years ago the local temperature started to warm again, followed by a more rapid warming in the last 50–100 years that coincides with present-day disintegration of ice shelves and glacier retreat.”

Co-Author Dr Nerilie Abram formerly from British Antarctic Survey and now with the Research School of Earth Sciences, at The Australian National University says, “The centuries of ongoing warming have meant that marginal ice shelves on the northern Peninsula were poised for the succession of collapses that we have witnessed over the last two decades. And if this rapid warming that we are now seeing continues, we can expect that ice shelves further south along the Peninsula that have been stable for thousands of years will also become vulnerable.” Olivier Alemany, from the French Laboratoire de Glaciologie et Géophysique de l’Environnement was part of the expedition. He says, “The international polar science community has collected and analysed ice cores from Antarctica and Greenland as part of an effort to reconstruct the Earth’s past climate and atmosphere. Our team wanted to understand how the recent warming and the loss of ice shelves compared to the longer term climate trends in the region.”

Though this research makes a significant contribution to the understanding of the role that Antarctica’s ice sheets play in influencing future climate and sea-level rise it presently does not answer why. Rapid increased warming in this region and throughout the globe has clearly left scientists scratching their heads for answers, but given the current political environment in the West and East, many scientists are reluctant to limit their research in areas that produced present day global warming theories.

Contributor D. Chandler

3 Responses to "Antarctic Peninsula Team of Polar Scientists Add New Dimension To Climate Change"

  1. Yan   August 24, 2012 at 5:35 am

    Antarctica is a continent, not a peninsula, you ignoramus.

    Reply
    • Mael Menoret   August 24, 2012 at 5:59 am

      Yan can you read? Or do you really not know what the Antarctic Peninsula is? Yes Antarctica is a continent, and on that continent there is a large peninsula which is called the “Antarctic Peninsula” for rather self obvious reasons, ignoramus.

      Reply
    • guardian   August 24, 2012 at 8:23 am

      Yan, Yan.. YAN… we’re being nice to you. So what you’re really saying is that you didn’t know that the Antarctic Peninsula exist. Aah, I see you have a tendency to resort to name calling; really Yan, that says more about you than I could ever say. So I will not engage in the temptation to fire back.

      Oh, and by the way, Special Thanks Menoret for taking the time to straighten that guy out.

      Anyway, here is what Wikipedia says, hopefully you’ve learned a little something here. Oh and one more thing, any continent can have a peninsula on it and depending on who names the peninsula it can carry the same name as the continent. But for your own reference a peninsula is a piece of land that is bordered by water on THREE sides; one side short of an island!!!!!

      Antarctic Peninsula
      From Wikipedia, the free encyclopedia

      The Antarctic Peninsula is the northernmost part of the mainland of Antarctica. At the surface, it is the biggest, most prominent peninsula in Antarctica as it extends 1300 km from a line between Cape Adams (Weddell Sea) and a point on the mainland south of Eklund Islands. Beneath the ice sheet covering the Antarctic Peninsula, it consists of a string of bedrock islands that are separated by deep channels whose bottoms lie at depths considerably below current sea level and are joined together by a grounded ice sheet. Tierra del Fuego, the southern most tip of South America, lies only about 1000 km away across the Drake Passage.[1]
      The Antarctic Peninsula is currently dotted with numerous research stations and has multiple claims of sovereignty. The peninsula forms part of disputed and overlapping claims by Argentina, Chile and the United Kingdom. None of these claims have international recognition and the respective countries do not currently actively pursue enforcement.

      Reply

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