Drought - A Disaster Unfolding Over Time

Drought is a lack of precipitation that results in a water shortage. In the US, drought is the second most costly form of natural disaster and can have far-reaching health and safety consequences including reduced air quality, reduced quantity and quality of water, and an increased risk of...


Aaron Baker

Sep 27, 2021 • Updated Mar 14, 2022 • 5 min read

AreaHub will be adding drought data in the future.

Overview#

Drought is a deficiency of precipitation over an extended period of time, usually one or more seasons, resulting in a water shortage. Because droughts are the absence of precipitation rather than the presence of a specific event like a hurricane or earthquake, they can be difficult to predict and monitor. Droughts are sometimes described as “creeping phenomena” because they slowly impact many components of both the natural and socioeconomic worlds and operate on many different timescales. For example, droughts can reduce water availability necessary for productive farming, impact port and waterway transportation and supply chains, increase the probability of large-scale wildfires, reduce water quantity and quality that can lead to increased human illness and disease, reduce hydroelectric capacity, and cause major ecosystem disruptions that can lead to reduction or extinction of local species.

In the US, drought is currently the second most costly form of natural disaster behind hurricanes. NOAA maintains a database of disasters that equal or exceed $1 billion in damages (adjusted for inflation). Between 1980-2021 there have been 29 droughts in the US that have exceeded $1 billion in damages with an average cost of $9.6 billion per drought. Most of these 29 droughts were accompanied by extreme heat, which was responsible for over 4,000 deaths in the US.

The US Drought Monitor is a collaborative effort among several organizations including the USDA and NOAA that produces a map each week identifying regions of the US that are in drought. A five category system from Abnormally Dry (D0) to Exceptional Drought (D4) is used to classify conditions and is determined using several dozen objective indicators (including precipitation, soil moisture, and streamflow), local condition reports from over 450 expert observers around the country, and drought impacts that are used to subjectively support and validate the classification. Below is the current US Drought Monitor map followed by a table of the drought categories with descriptions and possible impacts.

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Although droughts occur naturally, human activity including water use and greenhouse gas emissions, is contributing to the frequency and intensity of droughts. Researchers from the Netherlands estimated that the human consumption of water between 1960-2010 increased the frequency of drought in North America by 25%. Increases in regional populations and intensive agriculture can deplete water resources (through increased pumping from groundwater, rivers, and reservoirs) that can take years to replenish and may permanently impact future water availability.

Climate change impacts drought in two important ways. Rising temperatures generally make wet regions wetter and dry regions drier. In wet regions, warm air absorbs more water leading to larger rain events. But in arid regions, higher temperatures cause water to evaporate more quickly. In addition, climate change has begun to alter large-scale atmospheric circulation patterns which can shift storm tracks from their typical paths. This change can magnify weather extremes, which is one reason why climate models predict the already drought-stricken US Southwest will continue to get drier.

Your Home and Drought#

Health and Safety#

Drought can have numerous and far reaching health and safety consequences. Severe drought can negatively affect air quality.Increases in the amount of suspended particulate matter from dust storms and wildfires that are more frequent during drought can irritate the bronchial passages and lungs and increase the risk of respiratory illnesses and infections. Other possible health implications include reduced quantity and quality of drinking water, increased risk of death or injury from heat exhaustion or heat stroke, and an increased risk of certain diseases. Dry and dusty soil conditions can increase the risk of Valley Fever--a lung infection caused by a fungus in the soil, and West Nile Virus can move into or increase in an area as a result of an increase in stagnant water that is used for breeding by mosquitos. Stress, anxiety, and depression may also increase as a result of economic and job losses related to businesses that rely on water including agriculture and landscaping.

Property Values#

Drought does not appear to have a widespread or consistent impact on property values. Under specific circumstances and in some regions, drought has caused a reduction in property values. For example, researchers at Clemson University found that waterfront properties in the Lake Hartwell region of South Carolina experienced a small decrease in value when the lake water levels receded as a result of drought. Similarly, in California and Colorado, properties in close proximity to wildfires--that occurred partially as a result of droughts--also experienced decreases in value.

What You Can Do#

NOAA and the National Weather Service have recommendations for indoor and outdoor water conservation before and during a drought. Before a drought, check plumbing for leaks, fix leaking faucets, choose appliances that are more water efficient, if you have a well check the pump periodically--if the pump turns on and off when water is not being used then you probably have a leak. During a drought, water can be conserved indoors by flushing toilets only when necessary, taking short showers instead of baths, catching shower water in a bucket and reusing it to water plants, using water efficient appliances and only using clothes and dishwashers when they are fully loaded.

Outdoors, water can be conserved before a drought by positioning and checking sprinklers so they do not apply water to paved areas, planting drought resistant lawn seeds and shrubs, using mulch around trees and shrubs to retain moisture in the soil, and adjusting lawn mower blades to at least three inches which encourage grass roots to grow deeper and hold soil moisture. During a drought, in addition to following all local and state water restrictions, avoid watering lawns or water only when needed and do so when temperatures are cooler, wash cars at a commercial car wash that recycles water, and do not use water to clean walkways or driveways. People in dry areas may not be able to avoid droughts, but they can do their part to conserve water and thereby contribute to their region's ability to manage limited water resources.

AreaHub’s Knowledge Center is updated regularly and provides information drawing upon scientific studies and sources.

Sources#