In fact the amount has fallen nearly a third compared with the last known data on this, which was produced covering 2003-2008. The fall in levels for the winter months is not quite as dramatic however. Much of the loss seems to have occured in specific regions though, mainly on the Canada Archipelago and also some areas to the North of Greenland. We obviously have much more data about these levels since we had the technology of satellites to measure them, But the Cryosat report has only covered the last two years. At the moment it would be difficult to tell if these fluctuations are significant until there is enough data to look at the long term trends.
Cryosat was established by the European Space Agency in 2010. The satellite sends down a radar pulse towards the ice floes and then measure the results with a built in altimeter. If you are interested in seeing a paper discussing the findings in depth you can find them on this site –http://onlinelibrary.wiley.com/doi/10.1002/grl.50193/abstract, the report was compiled by Professor Lazon who unfortunately died in an accident at the beginning of the year.
The polar scientist is a big loss to the Cryosat mission as he has developed a lot of techniques to help the project work effectively. We still don’t know exactly how the change in the ice cover might have an effect on the atmosphere and the Arctic ocean, but the Cryosat data will definitely play an important role in understanding this.
If you want to read more and keep up to date with this research there are lots of resources on the BBC website in the environmental section. Also many of the documentaries and reports are viewable on the BBC Iplayer application. Unfortunately you won’t be able to access these if you’re based outside the UK, although I found this useful method to allow me to watch Iplayer on my IPad. It uses a VPN server to hide your IP address so even when I’m based in the US, it looks like my IP address is originating from the UK.