| Drought is an extended period of exceptionally | | | | writer John Steinbeck in his award-winning novel |
| low precipitation. A drought can feature additional | | | | The Grapes of Wrath, many farm families had to |
| weather characteristics, including high | | | | abandon their land. |
| temperatures and high winds. Although low | | | | Drought and famine have severely affected areas |
| precipitation (rain, snow, or sleet) marks both | | | | throughout Africa. Beginning in the late 1960s, in |
| droughts and deserts, the two are different. A | | | | the Sahel region south of the Sahara Desert in |
| desert is a region that experiences low | | | | northern Africa, a prolonged drought contributed |
| precipitation as an everyday occurrence. A | | | | to the deaths of an estimated 100,000 people. |
| drought, on the other hand, is a temporary | | | | The region was struck again by drought in the |
| condition in which precipitation is abnormally low | | | | mid-1980s and early 1990s. War and drought in |
| for a particular region. Droughts may occur at any | | | | Ethiopia in the early 1980s brought about the |
| time in any part of the world and last anywhere | | | | starvation of an estimate one million people and |
| from days to weeks to decades. | | | | the forced migration of hundreds of thousands of |
| The U.S. National Weather Service recognizes | | | | others. Drought combined with social unrest |
| three categories of drought. A dry spell occurs | | | | continued to afflict many countries at the |
| when there is less than .08 centimeter (.03 inch) | | | | beginning of the twenty-first century. The African |
| of rainfall during a minimum of 15 consecutive | | | | nations of Djibouti, Eritrea, Ethiopia, Kenya, |
| days. A partial drought occurs when the average | | | | Somalia, and Sudan were all hit hard by a massive |
| daily rainfall does not exceed .02 centimeter (.008 | | | | drought that began in the late 1990s. Conflicts like |
| inch) during a 29-day period. An absolute drought | | | | the border war between Eritrea and Ethiopia |
| occurs when there is no measurable rainfall over a | | | | slowed the delivery of famine aid. Devastating civil |
| period of at least 15 days. The intensity of a | | | | wars also worsened the effect of drought in the |
| drought may be measured by the ability of living | | | | countries of Afghanistan and Tajikistan. The |
| things in the affected area to tolerate the dry | | | | unrelenting droughts were the worst those |
| conditions. Some plants quickly fall prey to | | | | countries had seen in decades. |
| droughts while others, such as cacti and mesquite | | | | The El Niño weather phenomenon typically |
| trees, survive dry conditions by either storing | | | | brings about droughts in various parts of the |
| water in their tissues or by going dormant (a | | | | world as it disrupts normal weather patterns. |
| state in which growth activity stops). Although a | | | | Perhaps one of the worst such droughts occurred |
| drought may end abruptly with the return of | | | | in Southeast Asia as a result of the 1997–98 |
| adequate rainfall, the effects of a drought on the | | | | El Niño period. The monsoon rains that normally |
| landscape and its inhabitants may last for years. | | | | drench the area each September were delayed. |
| Droughts have taken place around the world | | | | Consequently, the jungle fires set by farmers to |
| throughout history. Some scientists theorize that | | | | clear land were not damped by the usual rain, but |
| droughts brought about the migrations of early | | | | instead raged out of control, propelled by hot |
| humans. From 1876 to 1879, severe droughts in | | | | winds. The smoke from the fires hung over |
| China caused the deaths of millions of people | | | | Southeast Asia like a thick, dirty blanket. It quickly |
| from lack of food. In 1921, a drought along the | | | | became the worst pollution crisis in world history. |
| Volga River basin in Russia led to the deaths of | | | | At least 1,000 people died from breathing the |
| almost five million people, more than the total | | | | toxic air; several hundred thousand more were |
| number of deaths in World War I (1914–18). | | | | sickened. |
| The best-known American drought occurred on | | | | Soil that lacks humus (nutrient-rich material |
| the Great Plains region during the mid-1930s. | | | | resulting from decaying plants) and the binding |
| Labeled the Dust Bowl, the affected area | | | | property of plant roots cannot absorb or retain |
| covered almost 50 million acres in parts of | | | | moisture properly. Dry, crusty soil is easily moved |
| Colorado, New Mexico, Kansas, Texas, and | | | | by winds. The overgrazing of farm animals, the |
| Oklahoma. During this period, dust storms | | | | over cultivation of farmland, and the clear-cutting |
| destroyed crops and buried agricultural fields with | | | | of forests all contribute to such soil conditions, |
| drifting sand and dust. As depicted by American | | | | adding to the severity of droughts. |