Top alpine skiers have raised alarm over accelerating glacier loss during the Winter Olympics in Cortina.
Lindsey Vonn and Mikaela Shiffrin said the glaciers they trained on as children have largely disappeared.
They described the changes as immediate and impossible to ignore.
Italy, the host nation, has lost more than 200 square kilometres of glacier area since the late 1950s.
Scientists report that the decline has sped up sharply in the past two decades.
Glaciers once visible from Cortina have shrunk into small ice patches high in the Dolomites.
Athletes rely on glaciers for early-season training and consistent snow.
Many now face exposed rock, crevasses and flowing meltwater instead of skiable terrain.
Federica Brignone said the retreat she sees near her home worries her more for the planet than for sport.
The largest glacier in the region, the Marmolada, has halved in 25 years.
Researchers say it could mostly vanish by 2034 if global warming reaches about 2.7°C.
Limiting warming to 1.5°C could extend its life and save around 100 Alpine glaciers.
Glacier loss threatens water supplies, increases mountain hazards and raises sea levels.
It also endangers the future of winter sports and the number of viable Olympic host venues.
Athletes from several countries called for faster cuts in fossil fuel emissions.
They said the choices made this decade will determine how much ice survives in the Alps and worldwide.
