You can read all about this in my latest feature in Current Biology which is out now and freely accessible(NB: my features remain on free access only until the next issue appears, i.e. normally 2 weeks, sometimes 3, and they return to free access a year after publication):
Atlantic circulation keeps turning
Current Biology, Volume 22, Issue 20, R853-R856, 23 October 2012 doi:10.1016/j.cub.2012.10.013
I also took lots of photos at Hamburg - one of them appears on the first page of the feature, another below (that's not the hotel where I stayed) and another half dozen on my flickr photostream.