Droughts have always been a part of human history. But as average global temperatures continue to rise, droughts are likely to come on more often and be more severe than in the past. That, in turn, may affect our lives in far-reaching ways.
What Is a Drought?
It generally means an extended period (such as a whole season) without rainfall that leads to a water shortage or other serious problems.
Different groups define drought slightly differently. For example, the National Weather Service says it’s when a lack of moisture causes problems for humans, animals, and vegetation over a large area.
What Causes Droughts?
It’s normal for certain parts of the country or the world to be drier and to get less rain than in other regions. Drought happens when there’s unusually little or no precipitation for weeks or years.
Factors that can play a role in droughts include:
- Warmer weather that more quickly dries out ground moisture
- Changes in the jet stream (a fast, narrow current of air in the atmosphere)
- The average temperature of the ocean, which affects precipitation
- Changes in the local landscape
What Are the Types of Drought?
Scientists sort drought into five main types. Each has its own classifications and monitoring benchmarks.
Meteorological. This is when dry weather persists over an area. It could also include less rainfall and changes in the airflow to and from an area on the planet. You can monitor this by looking at weather patterns and forecasts.
Hydrological. Water shortages result from reduced stream flow and low levels in lakes and groundwater. This might limit the supply of clean, fresh water. You can easily see this type of drought by keeping track of rainfall or precipitation levels daily.
Agricultural. This is when drought affects the ability to grow crops. This type of drought is not limited to a lack of water but could also mean poor energy and sustainability in lands used to grow food.
Socioeconomic. Lack of water affects the supply of food and other goods. This kind of drought will greatly affect how you can afford to buy things you need, even beyond groceries.
Ecological. This can stunt vegetation growth, drive animals to extinction, or permanently change the landscape.
When more than one of these types happen at the same time, there is a good chance the drought will be stronger and worse.
Where Do Droughts Happen?
It’s more common in areas around the world that usually get little or no rain. In the U.S., those regions include the West Coast, the Midwest, and the Deep South. The deserts in Africa are another historically parched area. Anywhere near the equator on various continents can also lead to drought due to the dryness of land and air.
Droughts can strike anywhere in the world where dryness or periodical flooding is common. Global warming and climate change raise the intensity of these weather conditions.
How Are Droughts Classified?
Every Thursday, a federal-private consortium called the U.S. Drought Monitor publishes a color-coded map showing the dryness levels around the country. The measurements rely on several factors, including soil moisture and precipitation.
The five categories of drought are:
Abnormally dry (D0): Short-term dryness that affects crops and pastures and water supply.
Moderate drought (D1): Some damage to crops and pasture. Streams and reservoirs at low levels. You may be asked to voluntarily cut back on water use.
Severe drought (D2): Damage to crops and loss of pasture. Water shortages and restrictions.
Extreme drought (D3): Major crop and pasture losses. Widespread water shortages.
Exceptional drought (D4): Emergency shortage of water and widespread crop and pasture losses.
Link Between Drought and Global Warming
You may think that global warming is to blame for droughts. And researchers have found a strong connection between the two.
But it may be more accurate to say that climate change raises the chances that droughts will happen more often, be more intense, and last longer.
While climate change doesn’t necessarily create these water shortages, it can make them much worse and more common.
How Does Drought Affect Your Health?
Even if you live far from areas of drought, you might not escape the consequences. Health effects of drought can be far-ranging. Among them:
What Can We Do to Prevent Drought?
All of us can do our part. One important thing is to conserve water. But there are many other ways, including:
Use water-saving tools: This could be showerheads that have low-pressure gauges.
Switch to renewable resources: This could include getting your electricity from solar panels or wind power, or driving an electric or hybrid vehicle.
Cut back on fossil fuels: Use public transportation, walk instead of drive, or bike wherever you can.
Plant smart. Landscape your home with native plants. Reconsider your grass lawn, which soaks up a lot of water.
Reduce, reuse, recycle: You’ve probably heard this one before, but it is good to keep it in the back of your mind. Composting is one example. Buying products with less packaging is another.