The European Perspective
Skating on natural ice is much more organized in Europe than in North America. There is a long tradition of large scale public skating events and many skating clubs. Sweden and Holland in particular have a combination of lots of frozen lakes and ocean areas and a large, outdoor oriented, population. This has generated the critical mass needed to develop a good scientific understanding of risks and practices that are effective for reducing these risks.
There has been quite a bit written on ice assessment, behavior and science. Most of this is in Swedish or Dutch with only a little in English. We have much to learn from the broader European experience.
Links: The following are links courtesy of Dave Dermott and Sven Andersson.
English Language Links:
Dave has compiled a large set of articles and links on ice skating and kick sledding.
The Ice Handbook for Engineers: A good and practical overview of ice science written by Lennart Fransson. It covers sea ice as well as lake ice.
Sven Andersson's blog has a nice overview with lots of links.
The Think Ice website has several excellent articles on ice behavior. http://www.thinkice.com/
In particular, Johan Porsby's comprehensive page Situationsanpassad isvbedoming ('situational ice judgment') covers all reasonable forms of skateable ice (and a few that are not so reasonable). http://www.thinkice.com/glaciology/sv/situationis/situationis.htm
A couple other Swedish ice safety links:
The Bremer Eisvereins (Bremer Ice Association) was first established in the nineteenth century. They now have an extensive website about all things related to ice skating in Europe. There is also some coverage of ice sailing as well.
From Johan Porsby December 12th, 2011: a two minute, skate level, video of a tour, just a subway ride from Stockholm on great ice and a blue bird day.