Some of the Playing for Change stuff seems pretty cheesy (like, for example, when they dub Bono over a bunch of street musicians). But this one is both good and extremely cool. Fun with multitrack recordings!

The second movie is about some Danish Police officers stopping cyclists who are breaking the law.

Life continues to keep us busy here in Belgium, with visitors and some heavy systems testing for the satellite operations software at work, so I’m still kind of catching up on a backlog of stuff I’ve been meaning to write about. One is this very interesting talk I heard at the meeting in Lapland — but, hopefully, there’s more coming soon.

I know a few people probably regarded this work rather skeptically, but I thought it was cool, especially since the meeting was supposed to be on the relationship between solar physics and climate. The study (which is by Ruzmaikin, Feynman, & Yung) looked at Nile River water levels between AD 622-1470, which were the best part of a long archive of Nile data that has been recorded since the time of the Pharaohs. (Apparently even Shakespeare mentions a ‘Nilometer’ — that’s the authors’ word, not his — in Antony & Cleopatra.) Using a mathematical tool called Empirical Mode Decomposition (detailed discussion, for those inclined) they reveal some of the hidden frequency variations in the data.

Then they apply the same tool to records of Auroral activity at mid-latitudes over the same time period, which are a decent proxy for real solar activity. Just as the Nile was the source of life for ancient Egypt, and was therefore studied carefully, occurrences of the Aurora were considered to portend major events, and so medieval people kept detailed records of them as well. They conclude that there’s a connection between the Aurora (and thus, solar activity) and water levels in the Nile.

As I said before, I know some people were skeptical of their results, either because they question the validity of the EMD analysis or quality of the 1500-year-old data. But I think the work is pretty interesting, and serves as a reminder of the deeply complex system that is the natural world. (All the more reason to tread carefully with our natural resources and environment, since it’s potentially easy to wreck things). You can read the full paper here, and there’s another, similar study about Lake Victoria here.

Sorry I haven’t posted more updates in the last week since I got back from Lapland. It’s been really busy. Part of the problem is that I’ve been working to help break this huge story for Cyclocross Magazine. Check it out!