Here are the latest TOPAZ4 volume forecasts, in pictures and numbers (by pixel-count)
(T4 volume 071517: 7440 km³)
T4 volume 071817: 7220 km³
T4 volume 072617: 6270 km³ (loss rate 18th to 26th: ~120 km³/day, 1st half of July 170km³/day)
Two remarks.
- Speaking in relative terms, the Topaz4 volume loss for the fist half of July mimicked the Piomas one pretty closely (~26% - if my math is correct). Will be interesting to see if this continues. The June-losses were also very close, the relative losses in May though showed a huge difference .
- While the forecasts for the 23rd and especially the 27th are probably too fare out, I think they highlight how vulnerable the ice currently is, especially in the sector north of the Wrangle Island.
The predicted changes in this area (red polygon in the third pic) are staggering. All it needs is a unspectacular low (990hPa) in the latest ECMWF run (12h, see last image).
This might or might not come to pass. But I think it shows how assailable the ice there is. If we are unlucky we could see a lot of open water there by early August.
And then, just imagine a strong low over this area in the weeks that follow. It would have a lot of relatively warm water to play with (what A-Team called the dangerous zone?). ... but we'll see.
One shouldn't worry too much about the things that could be.