Sandstorms have been a major disaster for many Asian countries for centuries. Scientists have tried many ways to solve this problem and in China, a mass campaign has been started to help solve it.

Sandstorms are strong, dry winds that carry sand. They are often so thick that you cannot see the sun, and the wind is sometimes strong enough to move sand dunes. The four main places in the world where there are sandstorms are Central Asia, North America, Central Africa and Australia. Ren Jianbo from Inner Mongolia described a terrible sandstorm he experienced as a child in the desert. “To have been caught in a sandstorm was a terrible experience,” he said. “There was nothing to be done. It was the most frightening and the most dangerous situation I’ve ever been in. You just had to hope you’d survive. I thought I was going to disappear under the sand.”

Northwest China is part of the sandstorm centre in Central Asia. Sandstorms begin in desert areas. Sandstorms in China appear to have increased in recent years as a result of “desertification” (沙漠化). This is a process (过程) that happens when land becomes desert because of climate changes and because people cut down trees and dig up grass.

Sandstorms sometimes affect Beijing. Citizens wake up to an orange sky and strong winds that cover the city in a thick, brown-yellow dust. The storms sometimes continue all day and traffic moves very slowly because the thick dust makes it difficult to see. So when it comes, people are advised by experts not to go out. If they have to, they’d better wear masks.

The desert is only 250 kilometers away from the west of Beijing. To prevent it coming nearer, the government is planting trees. Already the government has planted more than 30 billion trees and plans to continue planting for the next five years.

An earthquake is a sudden shaking of the ground. It happens because there is movement in the earth’s crust.

Earthquakes usually come without warning. What should you do if this happens to you? Stay calm as the earth begins to shake and move. An earthquake is dangerous, but there are things you can do to protect yourself.

If you are inside when the earthquake starts, stay calm and get under a table or a bed. You need to have something strong around you to protect you from falling objects.

Do not stand near walls or windows and stay out of the kitchen. The kitchen is dangerous because there are so many glass objects. Also, never get into a lift during an earthquake.

If you are outside, stay calm and get to an open area as fast as you can. Stay away from buildings and trees. If you are in a car, drive to a place without trees or tall buildings. If you are close to the sea, try to get as far away from the water as possible. Earthquakes can cause huge waves (海浪) that can really hurt the people nearby.

When the earthquake is over, there is still plenty of danger. If you see a fire, quickly move outdoors to an open area. If you have a phone, use it only once to call your family or a friend. Too many calls will bring down the phone system. Your chances of survival (幸存) in an earthquake go up if you stay calm. Staying calm is difficult, but it can save your life.

A tornado (龙卷风) is a kind of strong storm with air which moves in a circle quickly. They can move over 200 miles per hour and cause a lot of damage (损坏). As they move across the land, they can easily pick up cars, trucks, and even houses, and then throw them very far. It is important to find a safe place if a tornado gets close.

A safe place could be a basement (地下室). If you are in a home without a basement, try to find a first-floor bathroom or a small room without windows in the middle of your house. You should curl up (蜷缩) into a ball and cover your head and neck with your hands.

But there are some people who actually want to get close to tornadoes. They are scientists who want to learn more about tornadoes. One of the best ways to do this is to get as close as possible to the tornado. They use special tools to measure (测量) what is happening in and around a tornado.

One special tool is called a tornado probe (探测仪). Inside the tornado probe, there are sensors (传感器) to measure wind speed, temperature, pressure, and direction. Some probes even have cameras, so the scientists can see and understand what it’s like to be in a tornado.

To be able to get these measurements, the scientists have to get a tornado probe near or into a tornado. Scientists will try to guess where a tornado will go next. Then they drive to that location and put down the probe. If they do not guess correctly, they pick up their probe and try another place. If they are right, the tornado will go near or even right over the probe. Then they take all of the measurements from the probe and use them to predict where future tornadoes may form (形成) and travel. And they can give people some warning to keep away from a dangerous tornado.