The Times’s Matthew Haag reports:

Pedestrians in New York City are usually aware of the dangers by their feet: cars, bicyclists, sidewalk grates.

Increasingly, a threat may be coming from above: ice falling from a building’s facade.

The danger is not new: The police warned of “falling ice slabs” from Manhattan towers in 1939. But the threat is greater today because of a surge in angular towers built from materials like glass and steel that actually promote more ice growth. The acceleration of climate change may also contribute to icing issues.

Last week, ice dislodged from a tower in Midtown and struck a 55-year-old man in the face. On Sunday, the police closed three blocks of Central Park South as ice fell from towers and crashed to the ground.

[Add falling ice from glass towers to a New Yorker’s list of worries.]

A climate for falling ice

While ice and snow may melt upon contact with a warm sidewalk or street, they adhere to the cold nooks and crannies of a building. It’s also easier for ice to form on energy-efficient buildings because they retain heat that otherwise could melt ice.