An unusually smooth ice surface has attracted hundreds of outdoor enthusiasts to the sea ice off Helsinki in recent days.
The smoothness of the sea ice is a rare occurrence, according to Jouni Vainio of the Finnish Meteorological Institute, and hasn't happened off the Helsinki coast for at least five or six years.
Finnish winter started a bit earlier than usual, Vainio noted, and the sea ice had time to thicken during the cold snaps of January.
"The weather became milder in February and the snow on the ice melted and the ice surface became watery. When the temperatures dropped again, the water that had formed on the surface smoothed out the holes in the ice and the surface froze very smoothly," Vainio explained.
However, Finnish authorities have warned that people should not venture out onto the ice without the proper safety equipment. Although the sea ice is currently quite thick, there are always streams or pockets where the ice might be considerably weaker than in the surrounding area.
The recent spring sunshine makes it even more difficult to assess the thickness of the ice.
The Finnish Swimming and Lifesaving Federation said on Tuesday that four people drowned in separate incidents in Finland in the first two months of this year.
The federation noted that all four — three men and one woman — died after falling through weak ice.
An average of 18 people drown in Finland every year as a result of falling through weak ice, with early spring tending to be a particularly dangerous time.
Aino Turtiainen-Visala of the Finnish Nordic Skating association, a body that specialises in ice safaris, told Yle that there are two golden rules when it comes to ice safety: never go out on the ice alone and always carry safety equipment.
"The bare minimum is a set of stitching awls around your neck, a decent pair of poles to test the ice, and a floating backpack with a throw line and a full change of clothes," Turtiainen-Visala advised.
Jouni Vainio of the Finnish Meteorological Institute meanwhile stated that the ice around the capital region's inner archipelago may be suitable for outdoor use for another couple of weeks or so, depending on the weather.
"The amount of sun and heat will gradually increase. At the point when temperatures are above zero all day, it's time to consider whether it's worth going at all," he said.
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