Drought is a serious environmental threat across the United States. Climate change exacerbates droughts by making them more frequent, longer, and more severe. The USGS works with state and federal partners to study, monitor, and help mitigate drought impacts across the U.S. now and into the future.
Drought
Check out the USGS Drought Website to see up-to-date news, science, and publications on drought and water supply.
USGS Water Science School
The USGS Water Science School teaches people of all ages about water! Check out some of their pages related to drought, groundwater, and water management to understand the effects of climate-induced droughts on human communities.
How does Climate Change Impact Droughts?
Defining drought may seem easy. If an area receives less rain or snow than expected over the course of a year, it can be classified as being in drought. The severity of drought increases over time depending on how long an area remains arid. However, there’s more to the story than solely if there isn’t enough rain or snow.
Droughts don’t just affect water stored in wetlands, lakes, and rivers, but also water below ground stored in aquifers and in the soil. When this groundwater gets used up, the dry ground can act like a sponge, sucking surface water straight in. The surface water-groundwater relationship gets even more complicated with snowpack. If snow melts too early in the year, water can move through the environment too quickly, causing the ground to dry up and become “thirsty” too soon. So even if there is “enough” water, the timing of the water may dictate whether an area is in a drought.
Climate change has further altered the natural pattern of droughts, making them more frequent, longer, and more severe. Since 2000, the western United States is experiencing some of the driest conditions on record. The southwestern U.S., in particular, is going through an unprecedented period of extreme drought. This will have lasting impacts on the environment and those who rely on it.
USGS Science Helps Communities Understand, Prepare, and Mitigate Droughts
The USGS employs its wide range of scientific expertise to study how droughts affect human and natural communities and how to effectively predict, prepare for, manage, and recover from water shortages. USGS research spans geographic and temporal scales, exploring everything from short, local “flash” droughts to long-term, large-scale “mega” droughts.
Our science helps to:
- Understand how climate change contributes to modern droughts
- Explore the effects of droughts on plants, animals, ecosystems, and communities
- Help develop water management strategies under drought conditions
- Develop tools to assess the severity of droughts and to predict future droughts
- Understand the connection between droughts and wildfires
- Use the fossil record to compare past droughts to current ones
USGS Data, Science, and Prediction
The USGS actively coordinates our drought research efforts among our many diverse scientists. Experts like water scientists, wildlife biologists, and geologists all work together to study droughts and their impacts. This effort strengthens our existing observation networks by investing in real-time data collection on rainfall, stream flows, and environmental impacts. With these improved data sets, USGS scientists are working to better understand when and how droughts occur. We are also developing models to help predict which communities and landscapes may be vulnerable to future droughts, as well as when, how long, and how severe those droughts might be. We provide this information to help cities and natural resource managers develop plans to prepare for future droughts and lessen the impacts of droughts on natural and human communities.
Additional Resources
Science
CASC Drought Research Highlights
The Colorado River Basin Pilot Project
Atmospheric Warming, Loss of Snow Cover, and Declining Colorado River Flow
Past Perspectives of Water in the West
Drivers and Impacts of North Pacific Climate Variability
Explore USGS research projects on drought and water availability under climate change.
USGS Integrated Drought Science Plan
CASC Drought Research Highlights
The Colorado River Basin Pilot Project
Atmospheric Warming, Loss of Snow Cover, and Declining Colorado River Flow
Past Perspectives of Water in the West
Drivers and Impacts of North Pacific Climate Variability
Wetlands in the Quaternary
SPARROW modeling: Estimating nutrient, sediment, and dissolved solids transport
State of the Science Synthesis on Transformational Drought: Understanding Drought’s Potential to Transform Ecosystems Across the Country
Natural Drought and Flood Histories from Lacustrine Archives
Identifying Characteristics of Actionable Science for Drought Planning and Adaptation
Balancing Water Usage and Ecosystem Outcomes Under Drought and Climate Change: Enhancing an Optimization Model for the Red River
Eco-drought Actionable Science Working Group
What causes drought?
A drought is a period of drier-than-normal conditions that results in water-related problems. The amount of precipitation at a particular location varies from year to year, but over a period of years the average amount is fairly constant. In the deserts of the Southwest, the average precipitation is less than 3 inches per year. In contrast, the average precipitation in the Northwest is more than...
When does a drought begin and end?
The beginning of a drought is difficult to determine. Several weeks, months, or even years might pass before people know that a drought is occurring. The end of a drought can occur as gradually as it began. The first evidence of drought is usually seen in records of rainfall. Within a short period of time, the amount of moisture in soils can begin to decrease. The effects of a drought on flow in...
Where in the Nation are droughts or very low flows occurring now? How can I see these sites on a map and get to the data?
To view the USGS streamflow information on drought, see the drought map on our WaterWatch site, which shows below-normal, 7-day average streamflow compared to historical streamflow for the United States. Links to additional maps and drought data are listed on the USGS Drought website and the National Integrated Drought Information System (NIDIS).
Why doesn't a drought end when it rains?
Rainfall in any form will provide some drought relief. A good analogy might be how medicine and illness relate to each other. A single dose of medicine can alleviate symptoms of illness, but it usually takes a sustained program of medication to cure an illness. Likewise, a single rainstorm will not break the drought, but it might provide temporary relief. A light to moderate shower will probably...
- Overview
How does Climate Change Impact Droughts?
Defining drought may seem easy. If an area receives less rain or snow than expected over the course of a year, it can be classified as being in drought. The severity of drought increases over time depending on how long an area remains arid. However, there’s more to the story than solely if there isn’t enough rain or snow.
Droughts don’t just affect water stored in wetlands, lakes, and rivers, but also water below ground stored in aquifers and in the soil. When this groundwater gets used up, the dry ground can act like a sponge, sucking surface water straight in. The surface water-groundwater relationship gets even more complicated with snowpack. If snow melts too early in the year, water can move through the environment too quickly, causing the ground to dry up and become “thirsty” too soon. So even if there is “enough” water, the timing of the water may dictate whether an area is in a drought.
Climate change has further altered the natural pattern of droughts, making them more frequent, longer, and more severe. Since 2000, the western United States is experiencing some of the driest conditions on record. The southwestern U.S., in particular, is going through an unprecedented period of extreme drought. This will have lasting impacts on the environment and those who rely on it.
Sources/Usage: Public Domain.Drought and Climate Change infographic. USGS Science Helps Communities Understand, Prepare, and Mitigate Droughts
The USGS employs its wide range of scientific expertise to study how droughts affect human and natural communities and how to effectively predict, prepare for, manage, and recover from water shortages. USGS research spans geographic and temporal scales, exploring everything from short, local “flash” droughts to long-term, large-scale “mega” droughts.
Our science helps to:
- Understand how climate change contributes to modern droughts
- Explore the effects of droughts on plants, animals, ecosystems, and communities
- Help develop water management strategies under drought conditions
- Develop tools to assess the severity of droughts and to predict future droughts
- Understand the connection between droughts and wildfires
- Use the fossil record to compare past droughts to current ones
Sources/Usage: Public Domain.Droughts bring bigger issues than just being too dry or too hot. The impact of droughts on the landscape can range from minor to disastrous. Curious about when a shortage of rainfall leads to an actual drought? Check out “Droughts: Things to Know.”
Sources/Usage: Public Domain.Historically, drought has been viewed in terms of its agricultural, hydrological, and socioeconomic impacts. How drought affects ecosystems is often not discussed. A new concept of ecological drought was developed to capture this emphasis on how drought impacts ecosystems.
Sources/Usage: Public Domain.USGS uses the “OneHealth” approach, which integrates wildlife, domestic animal, human, and environmental health to conduct research on the role of drought has humans and the surrounding ecosystem. USGS Data, Science, and Prediction
The USGS actively coordinates our drought research efforts among our many diverse scientists. Experts like water scientists, wildlife biologists, and geologists all work together to study droughts and their impacts. This effort strengthens our existing observation networks by investing in real-time data collection on rainfall, stream flows, and environmental impacts. With these improved data sets, USGS scientists are working to better understand when and how droughts occur. We are also developing models to help predict which communities and landscapes may be vulnerable to future droughts, as well as when, how long, and how severe those droughts might be. We provide this information to help cities and natural resource managers develop plans to prepare for future droughts and lessen the impacts of droughts on natural and human communities.
Additional Resources
Science
CASC Drought Research Highlights
Droughts of the future will be hotter, longer-lasting, and larger than droughts of the past. CASC researchers are working to understand how these droughts will impact important natural resources across the country. Learn more about this work below.The Colorado River Basin Pilot Project
USGS expertise together with our vast regional data sets and modeling capabilities, provide an excellent opportunity to demonstrate the value and impact of a strategic and integrated science approach to delivering actionable intelligence to support decision making related to drought risk in the Colorado River Basin. The Pilot in the Colorado River Basin is underway to demonstrate more complex...Atmospheric Warming, Loss of Snow Cover, and Declining Colorado River Flow
Declining snow cover is playing a key role in decreasing the flow of the Colorado River, “the lifeblood of the Southwest,” by enabling increased evaporation. As the warming continues, increasingly severe water shortages are expected.Past Perspectives of Water in the West
In the intermountain west, seasonal precipitation extremes, combined with population growth, are creating new challenges for the management of water resources, ecosystems, and geologic hazards. This research contributes a comprehensive long-term context for a deeper understanding of past hydrologic variability, including the magnitude and frequency of drought and flood extremes and ecosystem...Drivers and Impacts of North Pacific Climate Variability
Climate model forecasts indicate an increase in extreme hydrologic events, including floods and droughts, for California and the western U.S. in the future. To better understand what the consequences of this future change in climate may be, USGS scientists are studying the frequency, magnitude, and impacts of past hydroclimate variability and extremes in the region. This project produces well... - Publications
- Science
Explore USGS research projects on drought and water availability under climate change.
USGS Integrated Drought Science Plan
The USGS National Integrated Drought Science Plan seeks to improve understanding of drought processes and impacts on human and natural systems through coordinated and multidisciplinary data collection, synthesis, analysis, and predictions generated from Mission Areas and a variety of partnerships. The long-term goal is to provide decision support tools and technologies to stakeholders for...ByFilter Total Items: 13CASC Drought Research Highlights
Droughts of the future will be hotter, longer-lasting, and larger than droughts of the past. CASC researchers are working to understand how these droughts will impact important natural resources across the country. Learn more about this work below.The Colorado River Basin Pilot Project
USGS expertise together with our vast regional data sets and modeling capabilities, provide an excellent opportunity to demonstrate the value and impact of a strategic and integrated science approach to delivering actionable intelligence to support decision making related to drought risk in the Colorado River Basin. The Pilot in the Colorado River Basin is underway to demonstrate more complex...Atmospheric Warming, Loss of Snow Cover, and Declining Colorado River Flow
Declining snow cover is playing a key role in decreasing the flow of the Colorado River, “the lifeblood of the Southwest,” by enabling increased evaporation. As the warming continues, increasingly severe water shortages are expected.Past Perspectives of Water in the West
In the intermountain west, seasonal precipitation extremes, combined with population growth, are creating new challenges for the management of water resources, ecosystems, and geologic hazards. This research contributes a comprehensive long-term context for a deeper understanding of past hydrologic variability, including the magnitude and frequency of drought and flood extremes and ecosystem...Drivers and Impacts of North Pacific Climate Variability
Climate model forecasts indicate an increase in extreme hydrologic events, including floods and droughts, for California and the western U.S. in the future. To better understand what the consequences of this future change in climate may be, USGS scientists are studying the frequency, magnitude, and impacts of past hydroclimate variability and extremes in the region. This project produces well...Wetlands in the Quaternary
Wetlands accumulate organic-rich sediment or peat stratigraphically, making them great archives of past environmental change. Wetlands also act as hydrologic buffers on the landscape and are important to global biogeochemical cycling. This project uses wetland archives from a range of environments to better understand how vegetation, hydrology, and hydroclimate has changed on decadal to multi...SPARROW modeling: Estimating nutrient, sediment, and dissolved solids transport
SPARROW (SPAtially Referenced Regression On Watershed attributes) models estimate the amount of a contaminant transported from inland watersheds to larger water bodies by linking monitoring data with information on watershed characteristics and contaminant sources. Interactive, online SPARROW mapping tools allow for easy access to explore relations between human activities, natural processes, and...State of the Science Synthesis on Transformational Drought: Understanding Drought’s Potential to Transform Ecosystems Across the Country
Drought events have cost the U.S. nearly $245 billion since 1980, with costs ranging from $2 to $44 billion in any given year. However, these socio-economic losses are not the only impacts of drought. Ecosystems, fish, wildlife, and plants also suffer, and these types of drought impacts are becoming more commonplace. Further, ecosystems that recover from drought are now doing so under different clNatural Drought and Flood Histories from Lacustrine Archives
Previous work performed as part of the USGS Holocene Synthesis project illuminated complex centennial-scale patterns of drought and wetter-than-average conditions across the North American continent interior during the past two millennia, where paleorecord data coverage is sparse. In order to explain the patterns of naturally-occurring drought, floods, and storms for the past, identified by the...Identifying Characteristics of Actionable Science for Drought Planning and Adaptation
Changing climate conditions can make water management planning and drought preparedness decisions more complicated than ever before. Resource managers can no longer rely solely on historical data and trends to base their actions, and are in need of science that is relevant to their specific needs and can directly inform important planning decisions. Questions remain, however, regarding the most efBalancing Water Usage and Ecosystem Outcomes Under Drought and Climate Change: Enhancing an Optimization Model for the Red River
Hydrologic drought and declining water availability are among the foremost stressors of stream ecosystems in the Red River basin. Resource managers face the challenge of apportioning scarce water resources among competing uses, but they lack a systematic framework for comparing the costs and benefits of proposed water management decisions and conservation actions. In 2016, Co-PIs Neeson and MorenEco-drought Actionable Science Working Group
The USGS National Climate Change and Wildlife Science Center (NCCWSC) is currently engaged in an Ecological Drought initiative, focused on understanding the impacts of drought on natural ecosystems across the country. This project was designed to support the Ecological Drought initiative by creating a USGS EcoDrought Actionable Science Working Group. The goal of this working group was to identify - Data and More
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What causes drought?
A drought is a period of drier-than-normal conditions that results in water-related problems. The amount of precipitation at a particular location varies from year to year, but over a period of years the average amount is fairly constant. In the deserts of the Southwest, the average precipitation is less than 3 inches per year. In contrast, the average precipitation in the Northwest is more than...
When does a drought begin and end?
The beginning of a drought is difficult to determine. Several weeks, months, or even years might pass before people know that a drought is occurring. The end of a drought can occur as gradually as it began. The first evidence of drought is usually seen in records of rainfall. Within a short period of time, the amount of moisture in soils can begin to decrease. The effects of a drought on flow in...
Where in the Nation are droughts or very low flows occurring now? How can I see these sites on a map and get to the data?
To view the USGS streamflow information on drought, see the drought map on our WaterWatch site, which shows below-normal, 7-day average streamflow compared to historical streamflow for the United States. Links to additional maps and drought data are listed on the USGS Drought website and the National Integrated Drought Information System (NIDIS).
Why doesn't a drought end when it rains?
Rainfall in any form will provide some drought relief. A good analogy might be how medicine and illness relate to each other. A single dose of medicine can alleviate symptoms of illness, but it usually takes a sustained program of medication to cure an illness. Likewise, a single rainstorm will not break the drought, but it might provide temporary relief. A light to moderate shower will probably...