At the moment in this website 6 locations are monitored.

In each location a video camera is positioned in order to record a stream of water. The images recorded are sent to our AI system that segments the image into parts: ice, snow, water, and other. The graphs show the percentage of ice, snow, and water for a given day.

Data is updated every day.

No. There is part of the image that is classified into other that is not shown.

Each daily value is an average computed across images recorded during the day. An image is used for the average only if light and noise levels meet certain quality conditions

The AI models are quite accurate. Nonetheless in some locations and under certain camera and light conditions, ice or snow might be detected even if they are not present. Also, the AI models tend to classify parts of the image as "other" if they are not 100% confident.

This happens for example in Kokkasaari. This is due to the amount of visibile water in the image. Sometimes the water level drops and more land is exposed.

Yes, there is an interplay between ice and snow. Snow might accumulate on top of a frozen river, and it might melt on slightly warmer days. This is why for a decreasing trend of snow, the percentage of ice might increase. Note also that the amount of snow in Winter is high because of the snow detected around the river.