Monitoring of Arctic ice is usually examined by display of the Sea Ice Extent (SIE), the area of the polar sea which is covered by at least 15% ice. This criterion is chosen because it is relatively stable (less noisy) than Sea Ice Area and easily and unambiguously monitored by satellite-borne IR radiometers, even through thick cloud cover.

There are other, more persuasive parameters however, such as Sea Ice Volume (SIV). The volume of sea ice cannot be determined by a single measurement, so it must be modeled and interpreted. Consequently, its results are open to criticism and skepticism, particularly from climate change denialists. However, measurements of SIV, if accurate, are much more indicative of what is going on in the Arctic than those of SIE, which can vary on a day-to-day basis due to local weather conditions.

The post-September minimum figures for SIV are consistent with the sudden autumn failure of the Arctic Ice to recover from the Summer Melt, as documented by SIE measurements. Another record falls in the Arctic this November. There is less ice on the water today than there has ever been on this date. For detailed analysis and commentary of these results, please look here:

http://neven1.typepad.com/blog/2016/12/piomas-december-2016.html#more

http://neven1.typepad.com/.a/6a0133f03a1e37970b01bb095c7465970d-800wi