Short announcement: I've put up a widget from Skeptical Science in the right hand bar that shows the planetary heat/energy imbalance that is built up due to greenhouse gas emissions. Generate your own customizable widget here if you have some space on your blog.
Last month I wondered "if and how last week's steep drop on all sea ice extent and area graphs will translate into volume numbers". Eyeballing the PIOMAS volume graph it seems it had an effect there as well, but since then numbers have climbed a bit faster than 2010 and 2011, though well below the 2007 trend line again. The difference with 2012 has gone down from 2161 to 1787 km3.
Here's Wipneus' version with the calculated "expected" 2013 values (dotted lines), based on the same date values of 1979-2011 and an exponential trend.
A caveat from Wipneus: "Note that the statistical error bars are quite large."