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Eleven Cities Tour in the Netherlands postponed

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Home >> Eleven Cities Tour in the Netherlands postponed

Though the icy cold has a tight grip on Europe: while the Main and Danube are closed for shipping, for some it is not cold enough. People in the Netherlands are concernd that the Eleven Cities Tour can't take place this year. Actually it couldn't since 1997 and everyone was really looking forward for this event in 2012. They always get excited if temperatures drop significantly below 0°C for a week or so. Up to 15.000 professional and amateur ice skaters and hundred thousands of spectators were looking forward for the first 200km / 120 miles race on natural ice in the Netherlands for the past 15 years. As ice skating is a national sport in the Netherlands, this event would had been quite a spectacle as the footage from 1997 shows. With the siberian cold in Europe everything looked great. Until yesterday, when the preparations where put on hold:

'The association says it needs ice six inches (15 centimeters) thick over the entire track before they can give the green light for the thousands of skaters to start the race before dawn. In some places along the route it was only three inches (8 centimeters). Wieling did not entirely rule out the possibility that the race could still be staged this year.'

Source: APNews

The Royal Dutch Meteorological Institute (KNMI) provides an ice growth model. The X-Axis shows the day ('Dag'), while on the Y-Axis lines above the Black Line indicate water temperatures, while lines below 0°C predict ice thickness ('ijsdikte'). The second chart provides synchronous air temperatures. A daily chart can be found on the KNMI Website. Spoiler: It doesn't look good.

Ice Growth Model KNMI

Short analysis: It doesn't look good at all. If you are really interested in graphs and statistics, continue with this article published in significance magazine. They provide an interesting graph about the likeliness of enough ice for the race in the 21th century (damn you, global warming) and a deeper level on analysis of the graphs.

Take a moment and have a look at the results. It puzzled me, that the average speed did not really improve that much during the last 50 years. But then I realized, that clap skates had been invented in 1997 (and are not really comfortable on a 200km tour?). They had never been used on the Eleven Cities Tour. Modern training methods did not change the speed that much over the last 50 years. It rather seems that an average speed above 25 km/h (15.5 miles / hour) is was never reached if the temperature was below -6°C. There are two interacting effect: Muscles are not as efficient if it is too cold,it is harder to provide energy as they need some energy for themselves (to warm up) and can't provide it to accelerate the skate (and this is what you call a simplification ;) ). But this is outruled by a second effect: The cooler it gets, the more black ice grows under the existing ice surface. It does not include as much air bubbles as slush ice, which grows from water saturated snow (where the bubble break the light and make the ice look white). Black ice / Congelation Ice is prefered for all kind of winter sports. Summary: The lower the temperatures the faster you could skate, if your muscles would be able to provide the energy. Thats why the authorities ordere soldieres to prepare the ice, to scratch off the slush ice on top. So we are back to the 15 cm / 6 inch problem: It actually refers to the thickness of the black ice formation, not to the thickness in total. The Alison Alaska Lake Ice and Snow Observatory Network provides a model for the growth of ice and the resulting water level below the ice: Click here

Another amateur video of the Elfstedentocht 1941 including occuyping Nazis (Minute 4:55 ff) can be found on Youtube as well: