Grand canyon
The Earth’s greatest gorge” the Grand Canyon is located in northwestern Arizona. Its vastness is 217 mile long, and its widest it spans over 17 miles across. It is not surprising that it has been designated one of the Seven Wonders of the World. The walls of the canyon are made of limestone, sandstone, lava and other rocks. As the day passes the rocks reflect different colors. Many tourists come to the canyon just to watch the rocks change color. Cottonwood and willow trees grow at the bottom of the canyon. Many varieties of cactus grow here as well. The canyon is also home to many animals, such as bobcats, coyotes, kangaroo rats and deer. Today about 4 million visitors come to the Grand Canyon each year. Seeing the Grand Canyon is always a breathtaking and unforgettable experience.
Tornadoes
A tornado is a very powerful column of winds which spirals around a center of low atmospheric pressure. It is one of the most destructive storms on earth. A tornado is also called a waterspout. A tornado is a long cloud which comes down from the sky. It is shaped like a funnel and consists of wind which whirls around and around extremely fast. In fact, the wind can reach a speed of more than 900 km per hour. Most tornadoes from a long a front(boundary) between cool, dry air and warm, humid air. Weather scientists are unable to know exactly when tornados will occur. Fortunately, the tornado is not usually very big and it does not last long.