A project by John Tibellisprognos.seWhen does the ice settle on your lake?
The normal dates when the ice settles and when it breaks up, lake by lake, for 84,743 Swedish lakes, from records going back to the 1870s. And anyone who's standing by the water can answer, with one tap, whether the ice is there now.
Winter, from north to south
The 34 lakes that are still watched every winter. Each bar runs from the day the ice settles to the day it breaks up.
The list
| Lake | Normal | Days | Last winter | Days |
|---|
One tap, from the shore
Visitors answer yes, no or partly, and the answers are counted up per lake and winter. No account, no address and no position: only the answer, the day, and something that makes an answer count once a day.
Measurements of how thick the ice is come from IsRapport, and are shown beside the dates, as they are.
How the dates are known
On these lakes someone still notes the day the ice settles and the day it goes, every winter.
Most were gathered by volunteer observers, the oldest long before the 1870s. Where a series has ended, it's shown as history, with its years.
For every other lake the normal dates are calculated from its size, depth, height and position: on average within nine days for the ice settling and five for the break-up.
Three honest limits
- It doesn't tell you about the ice where you're standing. The drill does.
- It doesn't take measurements. Those belong on IsRapport.
- It's about lakes. The sea and the archipelago have a different ice.
“A forecast is never a measurement. Drill, and measure.”
