OSLO, Norway — Skiing for Lise Lotte Storløkken, like many Norwegians, is a combination of personal passion and patriotic identity.
Storløkken, 70, was on her daily walk in the area of Skullerud, 15 minutes outside Oslo, on Feb. 14 in unusually warm weather — 5 degrees Celsius (41 degrees Fahrenheit). It was another day in an unseasonably warm winter that has left much of the country without snow.
The ski slope where she spent her childhood winters is green.
"We usually say that we are born with skis on our feet," Storløkken said. "Well, not any more. I have skied this area my whole life, but for the past three years I haven't even had skis on my feet."
Global warming has threatened winter sports, skiing in particular, around the world. But nowhere is that felt as strongly as in Norway. The country, with about 5.4 million residents, routinely dominates Olympic skiing competitions. The sport is an inextricable part of Norwegian history, and the word ski can be traced back to the Old Norse word skið, which roughly translates to "stick of wood."
But there's growing concern that the changing climate is threatening the region's wintry conditions, depriving the next generation of Norwegians of the chance to carry on the country's skiing traditions.
"I think of all the children," Storløkken said, nodding toward a group of children learning to ski on an artificial trail banked by machines that produce fake snow. "Will they really enjoy skiing in the future? Is this little strip of artificial snow enough?"
A particularly mild winter has left Norwegians at a loss. On the balmy Friday morning, children on trips with schools and preschools flooded the area around Skullerud, looking for places to ski. But apart from artificial trails, there weren't many others.
Researchers are working to develop climate-friendly ways to produce and store snow in an effort to preserve winter in times of global warming. But the concern is that these efforts will not be enough.
"I do fear that my future children never will experience what I have had in my own childhood: the joy of white snowy winters," said Mathilde Hoff, 25, a teacher who had taken her class skiing that morning.
This most recent January in Norway was the hottest in recorded history, according to the Norwegian Meteorological Institute, adding to many other reports that show how the Earth is warming at an accelerated pace in recent decades.
Reidun Skaland, a climate scientist at the Norwegian Meteorological Institute, said Oslo has seen similar conditions. Her research found that winter temperatures in Oslo have hit a record high, with average temperatures in December, January and February about 1.6 degrees Celsius (almost 3 degrees F) higher than normal.
And it's not just warmer winters that Norwegians have to contend with. It's also disappearing snow.
From around 1900 to about 1980, Norway experienced about 140 days of winter each year, with a snow depth of at least 25 centimeters (just under 10 inches). Now, they have about 100 days, Skaland said. And there is more sad news to come.
"We predict that in 30 years, the Oslo region will have about 60 days of winter with this snow depth," Skaland said.
As a consequence of the lack of natural snow, a new industry is arising in the Norwegian outdoors: artificial snow and indoor ski arenas.
"Artificial snow production has been on our agenda for decades already," said Camilla Sylling Clausen of the Norwegian Alpine Association, an interest group for Norwegian ski resorts.
Recently, Norway's first indoor ski arena opened, with the sole purpose of giving snow-hungry residents a feel of winter and a new place to ski.
The arena, called SNØ, has been tentatively embraced by skiers. And though Norwegians have been reluctant to ski indoors, the arena is now often packed with people.
The country's government knows that skiing is an important element in Norwegian living, and for the past few years, it has funded research to help the ski industry develop artificial snow.
Fredrik Kottmann, 47, a nurse and a keen skier from Oslo, has not yet tried skiing indoors. He, as so many Norwegians, longs for the outdoors in natural snow.
"This weather makes me depressed" Kottmann said as he tried to maneuver the icy ski trail next to the grass in Nordmarka, close to the national ski arena in Holmenkollen.
The snow in the arena is artificial. The area surrounding it, where Kottmann usually skis, was open and bare, the grass yellowish in the sun.
He unclicked his skis and shook his head.
"I might as well get my bike up from the basement," he said. "This is no use."