Some of the most interesting facts about drought are the different types, the causes, and the overall impact on social, environmental, and economical.
It is considered a natural disaster due to the fact that it is hazardous to human beings because it results in water shortage, damages to crops, and an increased death rate of livestock and wild animals.
Hydrological - impact is seen in river systems and reservoirs that are necessary for supporting hydroelectric power and hydrologic storage systems.
Meteorological - is the monitoring of atmospheric conditions for precipitation levels that lead to dry spells, the length a dry period and the overall amount of dryness.
Agricultural - rainfall shortages reduce soil moisture resulting in crop stress, which effects food production and farming.
Socioeconomic - when demand exceeds supply. Water shortages create a strain on products that are dependent on the water supply for production such as hydroelectric power, fisheries, food grains, etc.
According to Elizabeth Kitchen droughts can be caused by a number of things. The most important drought cause is related to how much water vapor is in the atmosphere because water vapor in the atmosphere is what causes precipitation.
When there are moist, low pressure systems, precipitation, such as rain, hail, sleet, and snow can occur. If the presence of dry, high pressure is above average, there will be less moisture available to create precipitation. This then results in a water deficit in areas they move over.
This can also occur when air masses are shifted by winds, resulting in dry, warm, continental air moving over an area instead of moist, cooler, oceanic air masses. El Nino, which affects the temperature of the ocean's water, also impacts levels of precipitation because during the years in which the temperature cycle is present, the air masses can be shifted above the ocean, often leading to places that are typically wet, dry and making places that are typically dry, wet.
Hunger and famine - These conditions often provide too little water to support food crops, through either natural precipitation or irrigation using reserve water supplies. The same problem affects grass and grain used to feed livestock and poultry. When it undermines or destroys food sources, people go hungry. When it is severe and continues over a long period, famine may occur.
Thirst - All living things must have water to survive. People can live for weeks without food, but only a few days without water.
Disease - It often creates a lack of clean water for drinking, public sanitation and personal hygiene, which can lead to a wide range of life-threatening diseases.
Wildfires - The low moisture and precipitation that often characterize droughts can quickly create hazardous conditions in forests and across range lands, setting the stage for wildfires that may cause injuries or deaths as well as extensive damage to property and already shrinking food supplies.
Social conflict and war - When a precious commodity like water is in short supply due to these conditions, and the lack of water creates a corresponding lack of food, people will compete—and eventually fight and kill—to secure enough water to survive.
Migration or relocation - Faced with the other impacts of these extreme conditions many people will flee the area in search of a new home with a better supply of water, enough food, and without the disease and conflict that were present in the place they are leaving. As seen during the 1930s Great Dust Bowl.
The Dust Bowl - in the 1930s, drought covered virtually the entire Plains for almost a decade (Warrick, 1980). The drought’s direct effect is most often remembered as agricultural.
Many crops were damaged by deficient rainfall, high temperatures, and high winds, as well as insect infestations and dust storms that accompanied these conditions. The resulting agricultural depression contributed to the Great Depression’s bank closures, business losses, increased unemployment, and other physical and emotional hardships.
Although records focus on other problems, the lack of precipitation would also have affected wildlife and plant life, and would have created water shortages for domestic needs.
For a map on the current US Drought Map click the link below. This map is updated weekly.
National Weather Service - http://www.drought.noaa.gov/
What is drought? - http://www.drought.unl.edu/whatis/dustbowl.htm
Elizabeth C. Kitchen • Writing for Education Updated Jul 8, 2011 • Bright Hub