Your guess
How heavy would a skier have to be for their pressure to noticeably melt the ice?
Why the pressure explanation fails
James Thomson predicted in the mid-19th century that pressure lowers ice's melting point; his brother Lord Kelvin confirmed it. John Joly applied it to gliding in 1886. Yet figure skating is best at −5.5 °C, ice hockey at −9 °C. By the pressure theory, skating below −4 °C would be impossible.
Friction heat?
Bowden and Hughes proposed friction heat instead: the gliding blade itself melts a thin layer of water. A 2014 study considers this the most important effect under typical conditions. But ice is already slippery when you stand still on it – before anything can rub.
Ice is wet all by itself
As early as 1842, Michael Faraday suspected a very thin premelted layer on the surface of ice. The molecules there have fewer neighbors to bond with and are more mobile. A 1998 measurement found around 32 nanometers at −1 °C and 11 nanometers at −10 °C; simulations find only a few molecular layers.
The latest proposal
In 2025 a team at Saarland University simulated sliding ice so cold that nothing can melt. Water molecules are dipoles: they briefly stick to each other and tear apart again. In the process the crystal lattice breaks down into a disordered layer. There is no consensus yet.
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