With passenger ferry services between the two capitals having come to a halt, culminating with Finland closing its borders to ferry passengers from April 11, the resulting lack of air pollution has made the sky clearer, as it has in many locations globally, and the Helsinki skyline can be seen from that high vantage point, Postimees says.

However, weather can also be a factor too, according to the Environmental Agency (Keskonnaamet) – air pollution disperses more quickly when there are strong winds, the agency's forecast models' chief specialist Jekaterina Služenikina says, making it hard to say to what extent the clearer skies are solely down to the lack of ferry traffic across the Gulf of Finland.

The European Space Agency's Copernicus Earth observation program does however show that the concentration of fine and superfine particles PM2.5 and PM10 fell considerably between March and the second half of April.

Finland's borders will be open to Estonian commuters who have a residence and employment contract there from May 14.

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