|Fig. 1 Ice extent as of July 15 (blue line)|
I have been updating the ongoing graph in that post daily.
This year's interest was sparked by this year's record low, pictured in Fig. 1, from Feb. 25 though 13 June.
That graph, Fig. 1, also shows that if 2015 continues on its current trajectory (red line), it could become the record year probably in August (click on the graph for a larger image).
Everyone is watching to see if 2015 will become the record low, taking the record low
|Fig. 2 (circa July 10)|
The reason it is being watched so closely is that there is also a slim chance that 2015 could become the first year of no summer ice cover in the Arctic.
If we review the events of 2012 that made it the lowest year on record so far, we might have a better grasp of the odds of 2015 becoming the record low, which could happen regardless of whether or not it becomes the first no-ice cover year in modern history.
There was speculation that a storm in early August, of 2012, helped 2012 take the record from the previous record year 2007:
Arctic sea ice extent during the first two weeks of August continued to track below 2007 record low daily ice extents. As of August 13, ice extent was already among the four lowest summer minimum extents in the satellite record, with about five weeks still remaining in the melt season. Sea ice extent dropped rapidly between August 4 and August 8. While this drop coincided with an intense storm over the central Arctic Ocean, it is unclear if the storm prompted the rapid ice loss. Overall, weather patterns in the Arctic Ocean through the summer of 2012 have been a mixed bag, with no consistent pattern.(NSIDC, emphasis added; cf. NY Times). If the storm did help establish the record in 2012, then the same may be true this year.
It may take an Arctic storm event if 2015 is to take the record from 2012 (e.g. there are other ways to lose ice extent in the absence of a similar storm; see this. Also, there are ways to gain ice extent; see this).
The situation in the Arctic is worth watching because the loss of ice cover in the summer means that the exposed waters there will warm faster, bringing more conditions for acceleration of the Greenland Ice Sheet disintegration and melt.
That is something scientists are quite concerned about (The Surge: A Forgotten Aspect of Sea Level Rise).
FINAL UPDATE: (click on a graph to enlarge)
|As of (Aug. 10)|
|As of (Sep. 15)|
The next post in this series is here, the previous post in this series is here.
Significance of methane feedback loops in the Arctic: