What Causes a Drought? How-to Monitor & Compare Over Time

Many areas around the world are facing the effects of a prolonged drought. This is a serious problem that can lead to widespread famine, the displacement of people, and the loss of livestock. So, what causes a drought? A drought is a period of unusually dry weather that can have serious consequences for the environment, agriculture, and the economy.

Droughts can be caused by a variety of factors, including changes in atmospheric patterns, reduced precipitation, and increased demand for water. Understanding the causes of droughts is important for developing strategies to mitigate their impacts and better prepare for future droughts.

Keep reading because, in this article, we will explore the various factors that can contribute to droughts, as well as the impacts of these dry spells on communities and the environment.

What Causes a Drought? 6 Major Factors

A drought is a period of prolonged dryness that can have severe impacts on both the environment and the economy. There are several factors that can contribute to drought, including natural climate patterns, human activities, and a lack of water management.

1. Lack of Rainfall: One of the most common is a prolonged period of below-average precipitation, such as rain or snow. When the amount of precipitation that falls in an area is not sufficient to replace the water that is lost through evaporation and transpiration, the soil becomes dry and plants begin to wilt and die.
2. El Niño-Southern Oscillation (ENSO): One of the main causes of drought is the El Niño-Southern Oscillation (ENSO), which is a natural climate pattern that occurs in the Pacific Ocean. During an El Niño event, warm water in the Pacific Ocean shifts eastward, causing changes in the jet stream and resulting in dry conditions in some areas and wet conditions in others.
3. La Niña: Droughts can also be caused by the opposite climate pattern, known as La Niña, which is characterized by cool water in the Pacific Ocean and can lead to dry conditions in certain regions.
4. Human Activity: Another factor that can contribute to drought is human activity. The increasing demand for water for agricultural, industrial, and domestic use can lead to overuse and depletion of water resources, especially in areas with limited water supply.
5. Climate Change: In addition, climate change can exacerbate the effects of drought by increasing temperatures and reducing the amount of precipitation in certain areas.
6. Lack of Water Management: Finally, a lack of water management can also contribute to drought. Poor water management practices, such as inefficient irrigation techniques or inadequate water storage infrastructure, can lead to the overexploitation of water resources and exacerbate the effects of drought.

How are People Affected by Drought?

A drought can have wide-ranging impacts on people, their livelihoods, and the environment.

• The lack of water can lead to crop failure and loss of livestock, which can cause food shortages and malnutrition. It can also lead to job losses as farmers are forced to leave their land.
• Drought can also lead to increases in waterborne diseases as people are forced to drink contaminated water.
• In addition, it can cause mental health problems such as anxiety, depression, and post-traumatic stress disorder.

The best way to protect yourself from the impacts of drought is to be prepared. Make sure you have enough food and water stored in case of a drought. And be sure to stay informed about the latest drought conditions, so you can take steps to protect yourself and your family.

How Does Drought Contribute to Famine?

Drought is a long period of dry weather during which there is not enough precipitation to support the growth of plants. When drought conditions persist for months or years, they can lead to widespread food shortages and famine.

• When an area experiences drought, the crops that are grown there may fail or produce significantly smaller yields than usual.
• This can lead to a shortage of food, which can then result in famine if the situation is not addressed.
• In addition to crop failures, drought can also affect the availability of food in other ways.
• For example, it can lead to the death of livestock, which can be a major source of food in many parts of the world.
• Drought can also lead to the contamination of water sources, which can make it difficult for people to obtain clean water to drink.
• When combined, these factors can create a serious humanitarian crisis, especially in areas where people are already struggling to meet their basic needs.

Who are the Most Affected by Drought?

Drought disproportionately affects the world’s poorest people.

• Lack of water can lead to malnutrition and dehydration, which are both major contributors to death. In fact, drought is one of the main drivers of humanitarian crises.
• Drought also affects livelihoods. Farmers may lose their crops and livestock, which can lead to loss of income and food insecurity. This can cause serious financial hardship and force people to migrate in search of better conditions.
• While drought has many negative impacts, indigenous peoples are among the most affected. They often rely on natural resources for their livelihoods and have cultural ties to the land that make them particularly vulnerable to its effects.
• Climate change is making droughts more frequent and intense, which magnifies these impacts.

How Does Drought Lead to Flooding?

Drought can lead to flooding in a number of ways.

1. Hard, dry soil: Drought conditions can cause the soil to become dry and hard, making it more difficult for water to soak into the ground. When heavy rainfall does occur, it can run off the hard soil surface, causing flash floods.
2. Reduced dam and reservoir capacity: Drought can reduce the capacity of dams and reservoirs, making them less able to hold water. This can lead to flooding downstream if heavy rainfall occurs while water levels are low.
3. Increased risk of wildfires: Drought conditions can increase the risk of wildfires, which can contribute to more flooding. As the vegetation burns, the soil becomes less absorbent and more prone to erosion, and during heavy rains, this can cause more runoff and landslides.
4. Lack of Rainfall: One way is when the lack of rainfall leads to lower water levels in rivers and reservoirs. This can cause problems when there is a sudden downpour of rain, as the water has nowhere to go and so builds up, leading to flooding.
5. Soil Erosion: Another way that drought can lead to flooding is through soil erosion. When there is no water to hold onto the soil, it becomes dry and loose. This means that when it does rain, the water can easily wash away the top layer of soil, taking with it anything that was rooted in it. This can create huge amounts of debris, which can then block drains and cause flash flooding.

Does a Drought End When it Rains?

Not necessarily. While rain can certainly help alleviate drought conditions, drought does not necessarily end when it rains. The amount and distribution of rainfall, as well as the duration of the drought and the amount of water that has been lost, are all factors that can determine whether a drought will end after it rains.

• In general, droughts tend to end when an area experiences a prolonged period of above-average precipitation, which replenishes the water that has been lost during the drought.
• However, this can vary depending on the specific circumstances of the drought.
• For example, if an area has experienced a severe drought that has lasted for several years, it may take more than one rainy season to fully recover from the drought.
• It’s worth noting that droughts can also end due to other factors, such as changes in temperature or humidity.
• In some cases, droughts can be broken by a sudden, extreme weather event, such as a tropical storm or hurricane, which can bring a large amount of rainfall to an area in a short period of time.
• However, these events can also cause other problems, such as flooding, landslides, and damage to infrastructure.

How Do We Monitor Droughts?

Droughts are monitored through a variety of methods, including satellite imagery, ground observations, and climate models. Drought conditions can also be inferred from changes in vegetation, stream flow, and other hydrological indicators.

1. Satellite imagery is a useful tool for monitoring drought because it provides a synoptic view of large areas of the earth’s surface.
2. Ground observations are important for providing more detailed information about local conditions.
3. Climate models can be used to simulate the effects of different meteorological conditions on drought development and help forecast future drought conditions.
4. Vegetation cover is an important indicator of drought because it responds quickly to changes in moisture availability.
5. Streamflow is another key hydrological indicator that can be used to monitor drought conditions.
6. Soil moisture content is another important factor that is often monitored to assess drought severity.

How Do We Compare Droughts Over Time?

There are several ways to compare droughts over time:

1. Rainfall records: One way to compare droughts over time is to look at historical rainfall records. By comparing the amount of rainfall that occurred during a drought to the average or normal amount of rainfall for that time of year, you can get a sense of how severe the drought was.
2. Drought indices: There are several drought indices that can be used to compare droughts over time. These indices take into account various factors, such as precipitation, temperature, and soil moisture, to provide a single number that represents the severity of the drought. Some common examples include the Palmer Drought Severity Index (PDSI), the Standardized Precipitation Index (SPI), and the Keetch-Byram Drought Index (KBDI).
3. Remote sensing: Remote sensing techniques such as satellite imagery can be used to compare drought conditions over time by observing vegetation’s greenness and moisture content.
4. Hydrological data: Comparing hydrological data such as stream flow, reservoir levels, and groundwater levels over time to assess the water availability and how it changes during drought.
5. Socio-economic factors: In some cases, researchers also include socio-economic factors in their comparison of droughts over time. For example, they might look at how droughts affected crop yields, water supply, or energy consumption in a particular area.

It’s important to note that different methods may be more appropriate for different regions and for different purposes. Furthermore, when comparing droughts over time, it is important to consider the potential effects of climate change and other factors that may have changed over time, such as population density, land use, and water management practices.

Video: What Causes a Drought

Conclusion

A drought is a long period of dry weather when there is not enough rain. Droughts can happen anywhere, but they are most common in areas where rainfall is low. There are many different factors that can contribute to drought.

• One of the most important factors is the amount of precipitation that an area receives. If an area experiences below-average rainfall for an extended period of time, it can lead to a drought.
• Other factors that can contribute to drought include high temperatures, strong winds, and lack of humidity.

Droughts can have a significant impact on both people and the environment. They can cause water shortages, and crop failures, and increase the risk of wildfires. Droughts can also lead to social and economic problems such as job losses and increased prices for food and water.

FAQs