Saturday, August 25, 2012

How much sea ice is lost daily?

How much sea ice is lost in the Arctic daily? What are your estimates (in square km and cubic km)? 

Paul Beckwith
Paul Beckwith, B.Eng, M.Sc. (Physics),
Ph. D. student (Climatology) and
Part-time Professor, University of Ottawa

Losses of 100,000 square kilometer per day loss of sea ice area are being reported by various sources. Images of ice speed and drift, in conjunction with ice thickness, would support this.

This rate of loss is as large as that lost during the August 3rd to 10th cyclone (700,000 to 800,000 square kilometers lost for the duration of the cyclone).

My prediction that we'll lose virtually all sea ice by September 30th, 2012, still seems very reasonable.

Sam Carana

I too estimate there have been losses of 100,000 square kilometer per day for over two months now.

The top image at my recent post on ice extent shows that extent has roughly halved in two months time, from over 12 million square km at the start of June to roughly 6 million square km at the start of August. That's a loss of about 6 million square km in two months time, or about 100,000 square km per day.

To date, this loss rate appears to have continued in August and shows no signs of decreasing yet.


  1. Virtually all ice lost THIS year?? This is too alarmistic even for me... but if that happens, what will happen to jet stream???


    1. Yes, Alexander, that's the right question. Accelerated warming in the Arctic is changing the Polar Vortex and Jet Stream. The changes look set to allow more cold air to escape from the Arctic, while at the same time allowing more warmer air to enter the Arctic. In other words, it's a positive feedback that will further accelerate warming in the Arctic, further increasing the danger that large amounts of methane will be released from warming sediments.

  2. Sea ice could be gone in roughly just over 30 days for the Arctic the way things are going. It's hard to at first recognize what your seeing in current picture of Earth from North polar view without ice cover. -Yet it may most likely veer off just shy.. -Still it is weather in Tampa, Florida concerning Tropical Storm Issac at Republican National Convention, at which all warming deniers gather that gets Big Media's focus..
    Even as NASA rocket to study what's happening above Earth is pulled back from pad to shelter it from possible effects of storm, -the politicians, the Republican politicians in Tampa, they won't take precaution to protect the United States, the people of the United States or even acknowledge danger of runaway global warming as real let alone man caused and what it means to the future of Earth -to future of all life on Earth..
    Well loss of ice on North Polar view can and will most certainly have consequence of CH4 release of unimaginable size and ferocity quite likely to extinguish life.. The only chance not is if there is Full out retooling to take on the task of stopping it and to restore Earth to balance with Nature's open systems made whole and healthy.. This could and would if done right zoom up the world economy, leave no one stranded, keep peace and hope alive. But that isn't on the politician's agenda or in Big Corporate script..
    The President won't take on the issue in order to get elected -that's because to preserve the lie, the lie most everyone wants to believe that we can live beyond our means to such a degree is basis of power for those in power and a illusion propped up which must be kept from exposure as National Security matter. Grass roots efforts to ask him for help could help him. Could give the strength to buck the system.

  3. NSIDC wrote on August 14 that the average pace of ice loss since late June has been rapid at just over 100,000 square kilometers (38,000 square miles) per day. However, this pace nearly doubled for a few days in early August during a major Arctic cyclonic storm. This was also reported in a recent post here.

    NSIDC has meanwhile reported that ice extent has now fallen below the 2007 minimum low. The Arctic Sea Ice Blog posted the following minimum annual extent data:
    2006 | 5.74877
    2007 | 4.1607
    2008 | 4.55469
    2009 | 5.05488
    2010 | 4.59918
    2011 | 4.30207
    2012 | 4.0892 (and running)

    A back-of-the-envelope calculation shows that if losses continued at 100,000 square km per day, zero could be reached in 40 days time. If further cyclones develop, zero could be reached even earlier than that.