The second Sea Ice Outlook of this year has been published. The SIO is organized by the Sea Ice Prediction Network (as part of the Arctic research program 'Study of Environmental Arctic Change', or SEARCH), and is a compilation of projections for the September 2015 Arctic sea ice extent, based on NSIDC monthly extent values. These projections are submitted by professionals as well as amateurs (public outlooks).
Here's the summary for the July report:
The median Outlook for September 2015 Arctic sea ice extent is 5.0 million square kilometers (km2), which is the same as the June Outlook median. The quartile range is 4.4 to 5.2 km2 (see Figure 1 in the Overview section, below). Contributions are based on a range of methods: statistical, numerical models, estimates based on trends, and subjective information. The overall range (excluding an extreme outlier) is 3.3 to 5.7 million km2. The median Outlook value is up from the July 2014 median value of 4.8 million km2. These values compare to observed values of 4.3 million km2 in 2007, 4.6 million km2 in 2011, 3.6 million km2 in 2012, and 5.3 million km2 in 2014. In general, the heuristic approaches forecast a mean September extent around 4.1 million km2, whereas the statistical and dynamical modeling approaches both suggest mean September extent near 5.1 million km2, with the dynamical modeling contributions showing a narrower range.
The lack of significant change between this month and last is largely related to the fact that most contributors did not change their forecast for July. Another factor could be the lack of significant atmospheric or oceanic forcing that would result in a large change from the June forecasts. A discussion of 11 dynamical model contributions shows no major differences compared to last month's report. This month's report also includes results from three regional predictions and a discussion of current ice and atmospheric conditions.
Read the entire report here.
And here's the figure showing all the projections (click for a larger version):
The September minimums for the last 10 years (in millions km2, found here):