People in Finland should think twice before venturing out on the ice as this year's lake cover is weaker than in previous years, according to environmental analysts.
Speaking on Yle's morning show, Finnish Environment Institute (Finnish acronym Syke) hydrologist Merja Pulkkanen said that warmer temperatures and rainfall have created wet patches and cracks on lakes across the country, such as one witnessed in Tampere's Näsijärvi.
Two people reportedly fell into the 2-3 metre-wide crack on Näsijärvi lake on Monday.
Recent measurements showed that the ice thickness of lakes in the south of the country varied between 15 and 40 centimetres. Pulkkanen noted that ice thickness should be at least five centimetres to be considered safe for one person to step on. The icy surface should also be clear, not slushy, according to the hydrologist.
"Snow cover can give a false sense of security when walking on ice. Under the snow cover, it should be possible to ensure that there is also enough clear ice," she said.
During spring, the load-bearing capacity of ice cover can change significantly throughout the day, according to the positioning and intensity of the sun.
Pulkkanen said that the best way to examine thickness is by drilling or making a hole in the ice with a steel spear or rod. The hydrologist added that people can ensure safer venturing by bringing ice picks, poles and ”a friend,” especially if moving around in unfamilliar areas.
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