Carcross Desert, Yukon, Canada
You probably wouldn’t expect to find a desert in the middle of Canada. And you would be right not to wait.
The world’s deserts are often huge, always impressive and sometimes covered in snow. But there is one of them that claims a more modest title: the Carcross Desertthe smallest desert in the world.
Com just 2.6 km²is about 1/4 the size of Monsanto Park, in Lisbon. Crossing it completely takes about 10 minutes.
Mass strangest feature of the Carcross Desert is not exactly its size. It’s… well, it’s pretty much everything else, says .
Carcross is located in the middle of Canada, surrounded by vast lakes and often covered in snow — probably the last place we would expect to find a sandy desert. And with some reason, because the Carcross Desert It’s not technically a desert .
“There are almost so many definitions of deserts and classification systems for as many deserts as there are in the world”, says the United States Geological Survey (USGS). But the system most accepted by the scientific community depends essentially on the precipitation.
“Extremely arid lands have at least 12 consecutive months without rain, drylands are less than 250 millimeters of annual precipitation and semi-arid lands have an average annual precipitation between 250 and 500 millimeters,” the USGS. “Arid and extremely arid lands are desertsand semi-arid prairies are generally designated as steppes.”
To be a true desert, then, Carcross would need to have a maximum of 25 centimeters of precipitation per year. But the nearest monitoring station records some impressive 27 centimeters. It is very little (by comparison, in Porto it rains 128.5 cm/year), but enough so that it cannot be considered an “arid land”.
The fact that the area remains so dry is due to simple geography. “The Carcross Desert is located in a rain shadow“explains Jonathan Erdmansenior meteorologist at weather.com. “Moist winds from the northeast Pacific are intercepted by the mountains to the west and south, stealing most of the rain and snow from these moisture-laden storms.”
“Furthermore, the wettest time of year along the Gulf of Alaska coast is also the time when extremely cold and dry arctic air masses accumulate in the Yukon Territory from Siberia and Alaska, further depriving the area of potential precipitation,” details Erdman.
Thus, the area would be more appropriately designated as dune field than as a desert, although “you can certainly call it a wet desert”, explained in 2018 the geologist Mrs. Lipovskyfrom the Yukon Geological Survey, to .
After all, it’s certainly not prairie: “With so much windblown sand and sediment, there’s no chance for the vegetation to regenerate,” Lipovsky added. “It’s a truly dynamic system.”
The history of Unique Carcross geography begins more than 10,000 years ago. At that time, North America was almost entirely covered in ice. Interestingly, the currently frigid Alaska was free of ice, but that’s another story.
“At the time, the Carcross would have had a kilometer of ice on it” Lipovsky explained. “You just can’t imagine it.”
But as the ice retreated, the glacial lakes that had existed in southern Yukon they have shrunk. In its place was sand and mud.; small beach islands stranded between lakes and smaller valleys.
That was the foundation of Carcross, but what sealed your fate as the “desert” that it is today were the newly exposed mountains and valleys in the area. The winds, stronger and more erratic as they blew through the valleys, sucked in sand from the southeast and brought it to the Yukon, resulting in the sandy landscapes so famous today.
“There is a misconception that Carcross results from a dry lake, but that is not the case,” Lipovsky said. According to the geologist, it was the combination of wind, water and the Ice Age that created the set of circumstances that gave rise to what is today the smallest desert in the world — which, by 2 centimeters, is not.
