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.
There are three types of tundra: arctic tundra, alpine tundra, and Antarctic tundra. In tundra, the vegetation is composed of dwarf shrubs, sedges and grasses, mosses, and lichens.Scattered trees grow in some tundra regions.he tundra is covered in marshes, lakes, bogs and streams during the warm months. Generally daytime temperatures during the summer rise to about 12 Â°C (54 Â°F) but can often drop to 3 Â°C (37 Â°F) or even below freezing. Arctic tundras are sometimes the subject of habitat conservation programs.