Facts about the sea estate of ice on Earth

  • View of Sheldon Glacier with Mount Barre in the background, seen from Ryder Bay near Rothera Research Station, Adelaide Island, Antarctica. Credit: British Antarctic Survey

    Sea ice. Credit: Ted Scambos, NSIDC

    An area high in the Andes in 1930. Credit: PA Wire/PA Archive/Press Association Images

    The same area in 2007 showing the shrinking glaciers Credit: Lonnie Thompson/PA Archive/Press Association Images

  • Facts about the sea estate of ice on Earth
    18.10.2014 13:52

    Every September there is a lot going on concerning the ice caps on Earth. On the one hand, we expect the results of the summer in the Artic ice cover, on the other hand, we keep an eye on the winter in the Antarctic sea ice. However, little is spoken about the glaciers on Earth. Let’s talk about all of this in the context of climate change.

    First of all, there is no controversy about the fact that the Earth is warming, despite some comments from “sceptics” on climate change about a “pause” in the last few years. The warming is still going up with perhaps a lower rate than recent years, but there are indications that this year could be one of the warmest on record.

    This warming does not mean that Earth is going to warm as a whole. Most places will be warming but also a few cooling. Moreover, a warmer world means more moisture in the atmosphere, all thus more rainfall or snowfall. Therefore, when combining more snowfall and cooler temperatures you will have an increase in ice. This is currently happening in the Antarctic. You would expect the same with the glaciers worldwide but unfortunately according to the World Glacier Monitoring Service:

    “The average mass balance of the glaciers with available long-term observation series around the world continues to be negative, with tentative figures indicating a further thickness reduction of 0.6 metres water equivalent (m w.e.) during the hydrological year 2012. The new data continues the global trend in strong ice loss over the past few decades and brings the cumulative average thickness loss of the reference glaciers since 1980 at 16 m w.e. (1 meter of thickness of ice is 0.9 m.w.e.)

    The Arctic's sea ice cover reached its minimum extent on 17th September 2014. Sea ice extent on that day was measured at 5.02 million square kilometres (1.94 million square miles). It was the sixth-lowest extent recorded since satellites began measuring sea ice in 1979. The number is above the 2012 record extent but is still below the long-term average.

    Since the late 1970s, the Arctic has lost an average of 53,900 square kilometres (20,800 square miles) of ice a year; the Antarctic has gained an average of 7,300 square miles (18,900 sq km). On 19th September 2014 this year, for the first time since 1979, Antarctic sea ice extent exceeded 20 million square kilometres (7.72 million square miles), according to the National Snow and Ice Data Center. The increase in the Antarctic does not make up for the loss in the Artic, even worst if we bear in mind the shrinking glaciers worldwide.

    That means that globally Earth is losing ice, (despite the increase in the Antarctic) –something we would expect in a world where concentrations of the greenhouse gas CO2 have passed 400 parts per million this year.

    By: Mario Cuellar