I'd like to make an update on the NSM.
I'll use yesterday's high-resolution image that I commented on.
In this image I have embedded an image with elevations, and thus thickness, (David E. Shean et al. 2019; data used first half of 2010) and velocities (WorldView 2011).
The NE-IS is fed upstream by a small tributary and, far to the east, by ice overflowing the Ice Rumples next to the PIG (north of the ZD). The ice of this IS is carried westward by the PIG and pushed towards the funnel between the Ice Rise Evan's Knoll and the PIG itself, where it recompacts.
This is the final part of the funnel that is visible in the image.
In the funnel the movement is parallel to the PIG and the speed gradually changes from zero, Ice Rise side, to that of the PIG itself, PIG side.
As for the thickness we can estimate it at 500m, see more.
Currently the movement of the PIG and the induced tensions lead to the opening of small marginal rifts in the NE-IS orthogonal to the PIG and the pieces of IS between two rifts are bent by the movement of the PIG until complete detachment and calving. This is the area indicated in red in the image (I also added a zoomed image of this area, image from the day before yesterday).
This area creates, PIG side, a shear force (even if relative), which ensures a progressive increase of the shear as we go upstream without abrupt increases. As a result there is almost no formation of marginal rifts in the PIG (which is positive).
Downstream there is final detachment of the pieces of IS with dynamic calvings: rapid initial movement of the icebergs and in many cases, given their size, their turning over.
This field of rifts, as well as the calving front migrate upstream and nothing seems to be able to stop this process, the only thing that can be hoped for is that this process is as slow as possible.
Clearly upstream, where the funnel widens, the process can only accelerate and there will be reunification with the already existing ZD and thus a detachment of the NE-IS from the PIG. But this process is expected to take several years.
What could accelerate it is a collapse of the part of the NE-IS already detached from the PIG and which currently provides support to the NE-IS upstream: this part is under pressure from the NE-IS upstream but it should resist, moving without breaking, for some time.
Following the detachment of the PIG from the NE-IS there may be some mini calvings (PIG side), one has recently arrived, but they should remain anecdotal.
To the west, on the front line, the large iceberg left over from the big calving (see third picture), already half detached from the PIG, should resist for a while.Indeed the rifts indicated r1 and r2 in the image are widening contentedly but their progression is slow (there is no modification of the rifts r3 and r4). This calving should have no effect on the PIG.
Click to enlarge