Define drought.
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Define drought.
Drought is a temporary but lengthy period of below average precipitation.
What is the difference between a drought and an arid region?
An arid region has a climate that is normally dry, while a drought is an extreme weather event with abnormally low precipitation.
What are the three main causes of drought?
The three main causes of drought are:
Meteorological (lack of rainfall)
Hydrological (lack of water sources replenishing)
Human causes like dam building
How can high-pressure systems cause drought?
High-pressure systems block low-pressure, rain-bearing weather systems, reducing or preventing rainfall.
What human activity reduces water flow downstream?
Dam building restricts the flow of water in a river, lowering water levels downstream.
How can agricultural practices contribute to drought?
Crops that need heavy irrigation, like cotton, remove large amounts of soil and groundwater. Deforestation also reduces moisture.
What is the link between global circulation patterns and drought?
The link between global circulation patterns and drought is that any changes in circulation cells like the Hadley cell can reduce precipitation in an area, increasing drought vulnerability.
How can El Niño and La Niña influence drought patterns?
El Niño changes storm patterns, causing droughts in some regions, while La Niña disrupts storms, leading to droughts in North and South America.
Which regions are most at risk from drought?
Areas most at risk from drought are those that are already arid regions, like Australia, the Middle East, Africa, North America and South America are prone to severe droughts.
True or false?
Global warming may increase drought frequency and severity.
True.
Global warming is expected to make droughts more frequent and severe in the future.
What makes droughts hard to measure?
Droughts start and end slowly over months or years, making them hard to definitively track compared to sudden hazards.
How long did the UK's 1970s drought last?
The UK's drought of the 1970s lasted for 16 months, from 1975 to 1976
How can drought lead to water contamination?
As water supplies deplete, the remaining water can become contaminated, causing diseases like cholera and typhoid.
What livelihood is impacted by crop and livestock losses in a drought?
Agriculture is the livelihood impacted by crop failures and livestock losses. This reduces land value.
How can drought increase conflict between groups?
Conflict or war can occur between people and countries when there is pressure on limited water supplies during a drought.
What percentage of the USA experiences drought annually?
In any given year, 14% of the USA is in a drought.
What was notable about the 2014–2016 drought in Ethiopia?
The 2014-2016 drought in Ethiopia was its worst in 40 years.
What was a social impact of the California drought?
People were asked to conserve water and faced hosepipe bans during the California drought.
What was an environmental impact of the Ethiopian drought?
Overgrazing and overcultivation during the Ethiopian drought led to desertification and land degradation.
What did the California government do in response to the drought?
The state government ran campaigns educating people to save water and brought in laws reducing water use by 25%.