What are the conditions necessary for the formation of sand dunes? Hi, Dunes are formed by interaction with the wind. Wind speeds of 10 to 20 mph,. are necessary for sand to start saltating under the direct pressure of the wind.
Winters are very harsh in Tundra climate. Winter months temperatures are usually between -18 and -50 degrees. Summer temperatures range from 35-50 degrees. High latitudes are the main cause of of the low temperatures. These areas mainly receive indirect sunlight.
Conditions are not right for a true tundra to form. Average annual temperatures are -70Â°F (-56Â°C). Tundra comes from the Finnish word tunturia, which means a barren land. The ground is permanently frozen 10 inches to 3 feet (25 to 100 cm) down so that trees can't grow there.he tundra is basically like a desert when it comes to precipitation. Only about 6 - 10 inches of precipitation (mostly snow) fall each year. Below the soil is the tundra's permafrost, a permanently frozen layer of earth.