A commenter at Real Science Ron C. says:
“There are two different methods of measuring arctic ice coverage. That is a good thing, just as it is good that we have both land stations and satellites to measure air temperature.
Microwave indices see more water than ice, while NIC index sees more ice than water in mixed conditions. So they will each have distinct results and trends.
My only concern is that the news only reports the microwave results, and ignores the equally valid NIC index. As of today NIC shows artic ice extent tracking slightly above 2007.
The data is available here. Select start year 2006 and month of August.”
Here is the graph: