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The Winter Olympics will begin in Utah this Friday. Why is Utah well suited, geographically, to host the Winter Olympics?

It's easier to pick sites for the Summer Olympics than for the Winter Olympics. For the summer games, you don't have to be concerned about snow or ice or whether mountains are close by. Selecting a site for the Winter Olympics can be pretty tricky. Four years ago during the Winter Olympic games in Nagano, Japan, there was too much snow, and several alpine events had to be postponed. In contrast, at Calgary in 1988, some Nordic events were in jeopardy of being cancelled because there was too little snow.

Since the Winter Olympics began in 1924, 17 different cities have hosted the games (Lake Placid and St. Moritz each hosted the Winter Olympics twice). Only once before has the Winter Olympics been held in the Rocky Mountains (Calgary). The most northerly location was Lilihammer in 1992 (61 degrees north), and Nagano was the most southerly location (37 degrees north). This year's games in the Salt Lake City area (about 40 1/2 degrees north) will be the third most southerly site (Squall Valley, California was second).

For the Winter Olympics, not only is snow mandatory, but mountains are sort of important too. Also, you have to hold the games close to where a lot of people live, and at a site that's fairly accessible. Not all that many places satisfy these requirements. If you go too far north, it's likely to be too cold, too dark or too sparsely populated. Go too far south, and snow conditions become iffy, unless the altitude is sufficiently high, and altitude creates its own set of problems.

In Nagano, the weather was a nightmare for the Olympic officials and competitors alike. Getting to the venues for the spectators wasn't exactly a walk in the park either. Things look pretty good now in the mountains near Salt Lake, in terms of the amount of snow on the slopes. This isn't due to luck, though. Salt Lake City wouldn't have even been considered as an Olympic venue if the snow criteria was a question. The average snowfall for the high mountains near Park City (the town closest to the sites for most of the skiing events) is about 350 inches (889 cm), whereas Salt Lake City averages about 55 inches (140 cm) a year. The Park City Ski Resort currently has a snow base of approximately 60 inches (150 cm) - there's a bit more snow on the upper slopes. This is more snow than for any of the Colorado ski resorts and considerably more snow than for Lake Placid and ski areas in the eastern US.

The sub-tropical jet and its neighbor to the north, the polar jet, have been rather vigorous over the western states this winter, and therefore a number of storms have dumped snow and rain across the Pacific coast ranges and the Rocky Mountains. The Sierra Nevada Mountains of California and Nevada and the Cascade Ranges of Oregon and Washington catch the brunt of these Pacific storms. For example, at Mammoth Mountain in California, the upper slopes are buried beneath about 108 inches (275 cm) of snow.

Because much of the Pacific precipitation is intercepted by the Sierra's, the prevailing westerly air currents are relatively dry upon reaching Utah. Most non-mountainous areas in the state receive less than about 10 inches (25 cm) of precipitation a year. Even though the Sierra and Cascade Ranges steal a good deal of the Pacific moisture, when these eastward moving storms encounter the mountains of northern Utah, the moist air is lifted and cooled orographically. The snow that results is often of a dry, powdery consistency, which is great for skiing. Whereas skis tend to skid on wet snow, they glide through powder snow. In essence, skiers are skiing on newly-fallen snow crystals that haven't as yet had time to metamorphose (change their shape and size). With these conditions, in general, skiers have more control and speed as they're schussing down the mountain. In contrast, wet snow adds viscous resistance and surface tension, which acts to decrease both speed and control.

Due primarily to orographic effects, the Wasatch mountains may receive upwards of 40 inches (102 cm) of liquid precipitation a year, which is about as much as Seattle or Washington DC can expect. In coastal areas, 10 inches (25 cm) of snow may produce 1 inch (2.5 cm) of melted snow, however, on the high peaks of Utah, 20 inches (50 cm) of snow or more may be needed in order to produce an inch of snow melt.

The principal mountain ranges in Utah are the north-south trending Wasatch Range and the east-west trending Uinta Range. Most of Utah's big ski resorts are found in the Wasatch mountains. The peak elevations are generally near 10,000 feet (3,226 m). The Wasatch ranges pick up a lot of snow, because they're no large ranges between them and the Sierra Nevada's to siphon off more precipitation. Even after the Sierra and Wasatch mountains have taken big gulps from the Pacific storms, there's usually plenty of snow left over for Colorado.

To the west of the mountains, at an elevation of about 4,200 feet (1,355 m), lies the Great Salt Lake. No other water body in the world, residing above 4,000 feet (1,290 m), is bigger than Salt Lake (it's approximately 75 miles [120 km] long and 50 miles [80 km] wide and 15 feet [5 m] deep). Since the lake has no outlet, it has a very high salt content - about 27% or about 8 times as salty as sea water. As a result, it never completely freezes. Thus, in winter, the open water has a moderating influence on nearby population centers, such as Salt Lake City. Additionally, water evaporated from the Great Salt Lake during the winter months can augment nearby mountain snowpacks with "lake effect" snows.

Mountains to the north and east of Utah act as barriers to cold winter blasts from Canada, so, even at higher elevations, temperatures aren't really that frigid. Because Utah is more than 700 miles (1120 km)from the nearest large body of water, the Pacific Ocean, sunny skies prevail for most of the year. For instance, in Salt Lake City, about 70% of the time the skies are sunny from April-October. In winter, though, the percent of sunshine dips to about 50%. This is about the same as Washington DC during the winter, but Washington receives less than 20 inches of snow a year.

So, Utah is blessed with abundant sunshine, moderate temperatures, and plenty of powder snow in the mountains. Moreover, Park City and most of the well-known ski resorts are within a 1 hour drive from Salt Lake City, one of the biggest and fastest growing cities in the western US. Thus, housing and transportation for Olympic competitors and spectators, while always a formidable problem, is not an impossible one. All-in-all, the mountain resorts near Salt Lake City are well suited for big-time winter sports. Good luck to all the competitors.