More made-up numbers

Dutch Skating Marathon Fading? - Dot Earth Blog - NYTimes.com

The agency first published the indicator in 2005 as a way of illustrating the pace of climate change to the Dutch. The agency acknowledged that “uncertainties surrounding this indicator are large,” with the lower limit of its calculations suggesting a race could be held once every 7 years and the upper limit suggesting it could take place once every 64 years. Once every 18 years was its best estimate. “Still, the conclusion that the chances are diminishing, over time, is robust,” it said.

There’s plenty of variability in the forecast for coming decades, as well. The agency also made projections for 2050 and concluded that the chances of holding an Elfstedentocht would be between once every 18 years in the most favorable case and once every 180 years, in the most unfavorable case. The first official race took place in 1909 and conditions have been good enough for the event to take place 15 times since then, with the most recent race taking place in 1997.