Drought is a long period of dry weather when there is no rainfall at all for weeks, months or even years. Rivers and streams stop flowing. Water in pools, ponds, or reservoirs dries out. Plants die.
Drought becomes a natural disaster. Some droughts occur for a very long period of time, and cause great hardship to people, plants and animals. Every year, droughts take place in many parts of the world, mostly in deserts. People plan for drought be storing water in wells, water tanks, etc. and by growing crops that can stay alive in hot and dry weather.How does drought effect the people?When drought occurs, lakes, rivers, and wells dry up.
In the hot and dry surrounding plants die, and some may even catch fire. Animals have to wander around to find food to eat and water to drink, and they eventually die if drought lasts for a long period. The strong wind blows the topsoil that is very fertile away and this makes it harder to grow crops in the future.
With no crops for food, people have to go get food from somewhere else, otherwise they would starve and die. Moreover, in poorer countries like Africa, drought brings disease, famine, and deaths.Famine often comes about when there is a long period of drought. It happens when a large number of people do not have enough to eat, since the hot sun kills the crops and dries up the water supplies. Animals that are kept for meat and milk die from starvation. The little amount of water that is available is usually very full of germs, and dirty. Moreover, when people are poor, they fight each other or attack the government. This often results in political instability or even war.
Types of droughtThere are many types of drought.* Permanent drought occurs in dry desert regions. There is hardly any rainfall, therefore deserts have drought all the time. However, desert people are good are surviving in these areas because they are used to the dry conditions and harsh environment.* Seasonal drought is a feature of places which are very dry for most of the year, with a short rainy season. Droughts here are predictable.
For example, the countries around the Mediterranean Sea have rains in winter and drought in summer.* Contingent drought occurs when the rainy season is very short. There is little rain, and sometimes it does not rain at all.* Unpredictable drought is found in areas where sudden rainfalls or rainbursts can be quite heavy but can’t be predicted.* Invisible drought is the effect of scanty rainfall which harms crops and wildlife but does not completely destroy them.Causes and Physical processes of droughtNo one really knows why droughts happen. They could be affected by the shape of the land, by ocean currents, or by how moist the soil is.
For example, The Kalahari and Sahara deserts in Africa are so far away from in land that no rains can reach them. Some people believe that drought is caused by a change in weather patterns and climate, including global warming and El Nino. El Nino is the shifting of warm water and a wet climate from the western to the eastern side of the Pacific Ocean.
This leads to major changes in the weather around the world.Are people to blame?If people take too much water from the well, rivers, and lakes, by building channels or dams to take water for crops, they could dry out riverbeds, lakes and wetlands. The drought would be more serious because of lack of water supplies. People also make the effects of drought worse by farming badly and letting too many animals feed on the grassland. This causes the deserts to spread or desertification.
In big cities people also use a lot of water. It is important to save water and use it wisely and carefully.Events: These are some of the most tragic disasters of the past.* One of the earliest recorded drought famines occurred in Rome in 436 BC.
Thousands of people drowned themselves rather than suffer the slow death of starvation and disease.* Between the years 610 -1619, there were 610 drought years in parts of China, where millions of China died.* In Europe during the Middle Ages a sudden warm weather phase occurred between 879 and 1162, causing failed crops, population migration and hundreds of thousands of deaths.* India suffered three famines in late 18th century and eight in the late 19th century.
Millions of people died.* The Sahel region of Africa suffered a bad drought in the 1980s. This led to a terrible famine. Ethiopia was the worst hit. Usually, during a drought, food can be brought in from areas where rains have watered the crops. But in 1980, no rain fell at all in Ethiopia, and over half of the country’s cattle died.
Ethiopia was too poor to buy food from other countries. During the famine, a long and violent civil war prevented food from reaching the people in greatest need. About two million people died of starvation.Drought PreventionDroughts cannot yet be prevented. Scientists have tried to make clouds produce rains, but it was not really successful.
However, scientists are getting better at forecasting and early warning when droughts are likely to occur. They sometimes use satellites to measure the temperatures of the surface of the oceans and to plot the progress of rain clouds. Hazard mapping can help in the forecast when drought is likely to happen in risk areas.Tree plantingTo reduce the effects of drought, it is necessary to plant a lot of trees in many places. Moisture evaporates from plants far more slowly than as it does from pools of water. Plants grown close to each other thus protect soil from water loss.
Trees can act as windbreaks, and their roots stop the soil blowing away in strong wind. In some countries dry, sandy soil is sprayed with a mixture of oil and rubber to stop it blowing about. Then seedlings of acacia and eucalyptus trees, which grow fast in dry soils, are planted. Their roots hold the soil together.Crops grow strong in the shade and shelter of the trees, and the trees themselves eventually provide valuable wood.Plant breeding and manureScientists are trying to help reduce the effects of drought by breeding different kinds of plants that can survive with little water. Already, drought-resistant crops such as millet and sorghum are being grown in several dry areas.
Putting animals manure and compost on dry soils helps them to hold water longer. These also bind the soil together and prevent it drying up and blowing away.