According to About.com, there are many causes for drought, but the most important one "relates to the amount of water vapor in the atmosphere, as this is what creates precipitation." Moist, low pressure systems tend to bring more rain, snow, sleet and hail, while dry hi...
Droughts can occur at any time during the year. A drought is usually determined by the lack of precipitation that falls during a period of time, but it can take a long time for its effects to be noticed.
Because they are caused by a reduction in the normal amount of rainfall a region receives, droughts can occur anywhere on the planet. For example, some parts of the Amazon River basin were struck by drought in 2005. However, some places are more susceptible to droughts ...
All droughts are ultimately caused by a lack of precipitation. This reduced precipitation does not have to be local; areas that receive water from rivers, for example, can be affected by a lack of precipitation thousands of miles away.
Droughts are caused by changes in land and sea surface temperatures, atmospheric circulation patterns and soil moisture content. A change in any one of these factors sets up a cyclical chain of events that can result in extreme climate conditions such as drought.
During a drought, the affected area has less water, which can cause plants to struggle and die. Droughts can also cause erosion and threaten animal populations.
Put simply, droughts are caused by a prolonged depletion of precipitation in a certain ecosystem or climate over a long period of time. Unlike normal dry spells, droughts are so severe that they can thoroughly dry out vast expanses of land, like deserts. Droughts can be...