Drought is a prolonged and widespread deficit in available water supplies that creates multiple stressors across ecosystems and communities. The U.S. Geological Survey Water Mission Area conducts drought research and modeling to improve drought prediction capabilities. The research focus is on understanding the hydrological, ecological, and economic ramifications of drought. The modeling focus builds on the research to provide predictive capacity for resilience planning at local, regional, and national levels. Prediction of the onset, severity, and duration of hydrologic drought conditions is critical for the USGS to identify and evaluate multi-sector responses to alterations in water availability.
The U.S. Geological Survey drought prediction science capacity includes monitoring, research, and modeling. Long-term water monitoring has allowed for identification of drought periods in the context of climatic variability and change, and for statistical trend analysis of continuous data to support earlier and more accurate detection of low-flow and drought conditions. Recent drought science research has focused on modeling and analysis of drivers of hydrologic drought.
In addition, the U.S. Geological Survey is exploring the usage of new data-driven methods (artificial intelligence and machine learning) to predict and deliver early warning of hydrological drought conditions at higher spatial and temporal resolution than currently available. These data-driven drought prediction models will provide useful information to stakeholders on drought onset, duration, and severity metrics (and their uncertainty) for surface water and groundwater.
Ongoing scientific inquiries and activities to support drought characterization and prediction include:
- Supporting the assimilation, screening, analysis, publication, archiving, and delivery of drought data from USGS and other sources;
- Developing stakeholder-relevant hydrologic drought metrics;
- Describing uncertainties associated with drought causes and effects;
- Incorporating the drivers of flash drought into predictive modeling;
- Establishing links between the effects of drought on wildfire, floods, and water quality; and,
- Developing regional- and national-scale prototype maps that will display streamflow drought conditions as well as predictions for weeks to months in advance.
Highlighted Publications
- Simeone, C., Foks, S., Towler, E., Hodson, T., and Over, T. (2024) Evaluating hydrologic model performance for characterizing streamflow drought in the conterminous United States. Water, 16, 2996. DOI: 10.3390/w16202996
- Simeone, C., Hammond, J., Archfield, S.A., Broman, D., Condon, L.E., Eldardiry, H., Olson, C.G., and Steyaert, J.C. (2024) Declining Reservoir Reliability and Increasing Reservoir Vulnerability: Long-Term Observations Reveal Longer and More Severe Periods of Low Reservoir Storage for Major United States Reservoirs. Geophysical Research Letters, 51, e2024GL109476. DOI: 10.1029/2024GL109476
Data releases related to U.S. Geological Survey drought prediction science.
Model inputs for machine learning models forecasting streamflow drought across the conterminous United States (ver. 2.0, September 2025) Model inputs for machine learning models forecasting streamflow drought across the conterminous United States (ver. 2.0, September 2025)
This dataset contains 3,229 feather files with time series of all model inputs for machine learning models predicting streamflow drought across the conterminous United States (CONUS). Files contain weekly time series of streamflow percentiles, meteorology, snow water equivalent, forecast meteorology, estimated water use, soil moisture, as well as lagged versions of these datasets. Values...
Metrics to Characterizing Periods of Anomalously Low Water Storage for Selected Reservoirs in the Conterminous U.S. from 1981 to 2020 Metrics to Characterizing Periods of Anomalously Low Water Storage for Selected Reservoirs in the Conterminous U.S. from 1981 to 2020
This metadata record describes a series of tabular datasets containing metrics used to characterize periods of anomalously low storage for select large reservoirs across the Conterminous United States for the climate years (April 1 – March 31) from 1981 to 2020. These data support the associated Simeone and others (2024) publication. The reservoirs in this dataset are those included in...
Low-Flow Period Seasonality, Trends, and Climate Linkages Across the United States Data Release Low-Flow Period Seasonality, Trends, and Climate Linkages Across the United States Data Release
This metadata record describes data that characterize low-flow period duration and seasonality, as well as trends and climate linkages at streamgages across the conterminous United States. These data are associated with a publication which looks to answer three questions about low-flow periods in the conterminous United States: (1) how long are these periods and when do they typically...
Data-Driven Drought Prediction Project Model Outputs for Select Spatial Units within the Conterminous United States Data-Driven Drought Prediction Project Model Outputs for Select Spatial Units within the Conterminous United States
This metadata record describes model outputs and supporting model code for the Data-Driven Drought Prediction project of the Water Resources Mission Area Drought Program. The data listed here include outputs of multiple machine learning model types for predicting hydrological drought at select locations within the conterminous United States. The child items referenced below correspond to...
Data-Driven Drought Prediction Project Model Inputs for Upper and Lower Colorado Portions of the National Hydrologic Geo-Spatial Fabric version 1.1 and Select U.S. Geological Survey Streamgage Basins (ver. 2.0, July 2025) Data-Driven Drought Prediction Project Model Inputs for Upper and Lower Colorado Portions of the National Hydrologic Geo-Spatial Fabric version 1.1 and Select U.S. Geological Survey Streamgage Basins (ver. 2.0, July 2025)
This metadata record describes a series of data sets of natural, climatic, and anthropogenic landscape features processed as model inputs for the Data-Driven Drought Prediction Project of the Water Resources Mission Area Drought Program. These data are linked to two different spatial units: the National Hydrologic Geospatial Fabric version 1.1 (nhgfv1.1) including their associated...
Streamflow Drought Metrics for Select United States Geological Survey Streamgages for Three Different Time Periods from 1921 - 2020 Streamflow Drought Metrics for Select United States Geological Survey Streamgages for Three Different Time Periods from 1921 - 2020
This metadata record describes a series of datasets containing metrics used to characterize drought for four sets of United States Geological Survey (USGS) streamgages in the conterminous United States (CONUS) for three different time periods between 1921 and 2020 outlined below. The streamgages used are a subset based on the criteria used in Geospatial Attributes of Gages for Evaluating...
U.S. Streamflow Drought During the Last Century: annual drought and low flow metrics, annual climate, and trends for the periods 1921-, 1951- and 1981-2020 (ver. 1.1, August 2025) U.S. Streamflow Drought During the Last Century: annual drought and low flow metrics, annual climate, and trends for the periods 1921-, 1951- and 1981-2020 (ver. 1.1, August 2025)
This dataset contains annual flow metrics quantifying drought and low streamflows for USGS GAGES-2 gages in the contiguous U.S. satisfying data completeness checks for the periods 1921-2020, 1951-2020, and 1981-2020. The dataset also contains annual climate variables from the USGS Monthly Water Balance Model (MWBM). The dataset provides trend analysis outputs for annual drought and low...
USGS monthly water balance model inputs and outputs for the conterminous United States, 1895-2020, based on ClimGrid data USGS monthly water balance model inputs and outputs for the conterminous United States, 1895-2020, based on ClimGrid data
This NetCDF represents the monthly inputs and outputs from a United States Geological Survey water-balance model (McCabe and Wolock, 2011) for the conterminous United States for the period 1895-01-01 to 2020-12-31. The source data used to run the water balance model is based on the National Oceanic and Atmospheric Administration's(NOAA, 2020) ClimGrid data for precipitation and...
Clusters of monthly streamflow values with similar temporal patterns at 555 HCDN sites for the period 1981 to 2019 Clusters of monthly streamflow values with similar temporal patterns at 555 HCDN sites for the period 1981 to 2019
This data release identifies 555 Hydro-Climatic Data Network (HCDN) streamgages in the conterminous United States during the period 1981-2019 which were grouped according to similarity in their temporal patterns of monthly streamflow.
Publications related to U.S. Geological Survey drought prediction science.
Hydrological whiplash: Highlighting the need for better understanding and quantification of sub-seasonal hydrological extreme transitions Hydrological whiplash: Highlighting the need for better understanding and quantification of sub-seasonal hydrological extreme transitions
In this commentary, we aim to (1) describe ways that hydrological intensification and hydrological whiplash (sub-seasonal transitions between hydrological extremes) may impact water management decision-making, (2) introduce the complexities of identifying and quantifying hydrological extreme transitions, (3) discuss the processes controlling hydrological transitions and trends in...
Authors
John C. Hammond, Bailey Anderson, Caelan Simeone, Manuela Brunner, Eduardo Munoz-Castro, Stacey Archfield, Eugene Magee, Rachael Armitage
Evaluating hydrologic model performance for characterizing streamflow drought in the conterminous United States Evaluating hydrologic model performance for characterizing streamflow drought in the conterminous United States
Hydrologic models are the primary tools that are used to simulate streamflow drought and assess impacts. However, there is little consensus about how to evaluate the performance of these models, especially as hydrologic modeling moves toward larger spatial domains. This paper presents a comprehensive multi-objective approach to systematically evaluating the critical features in...
Authors
Caelan Simeone, Sydney Foks, Erin Towler, Timothy Hodson, Thomas Over
Agricultural tile drains increase the susceptibility of streams to longer and more intense streamflow droughts Agricultural tile drains increase the susceptibility of streams to longer and more intense streamflow droughts
Streamflow droughts are receiving increased attention worldwide due to their impact on the environment and economy. One region of concern is the Midwestern United States, whose agricultural productivity depends on subsurface pipes known as tile drains to improve trafficability and soil conditions for crop growth. Tile drains accomplish this by rapidly transporting surplus soil moisture...
Authors
Seth Adelsperger, Darren Ficklin, Scott Robeson, Margaret Zimmer, John C. Hammond, Damon Hall, J.P. Gannon
Streamflow timing and magnitude during snow drought depend on snow drought type and regional hydroclimate Streamflow timing and magnitude during snow drought depend on snow drought type and regional hydroclimate
Communities around the world rely on snowmelt to meet water demands, and periods of lower than normal snow accumulation, snow droughts, can decrease water supplies. Leveraging 172 minimally disturbed and seasonally snow-covered watersheds, we developed an approach to examine the effects of cool & dry, warm & dry, and warm & wet snow droughts on streamflow timing and magnitude by...
Authors
John C. Hammond, Annie Putman, Theodore B. Barnhart, Graham A. Sexstone, Gregory McCabe, David Wolock, Aaron Heldmyer, Stephanie Kampf
Declining reservoir reliability and increasing reservoir vulnerability: Long-term observations reveal longer and more severe periods of low reservoir storage for major United States reservoirs Declining reservoir reliability and increasing reservoir vulnerability: Long-term observations reveal longer and more severe periods of low reservoir storage for major United States reservoirs
Hydrological drought is a pervasive and reoccurring challenge in managing water resources. Reservoirs are critical for lessening the impacts of drought on water available for many uses. We use a novel and generalized approach to identify periods of unusually low reservoir storage—via comparisons to operational rule curves and historical patterns—to investigate how droughts affect storage...
Authors
Caelan Simeone, John C. Hammond, Stacey Archfield, Dan Broman, Laura Condon, Hisham Eldardiry, Carolyn Olson, Jen Steyaert
Low-flow period seasonality, trends, and climate linkages across the United States Low-flow period seasonality, trends, and climate linkages across the United States
Low-flow period properties, including timing, magnitude, and duration, influence many key processes for water resource managers and ecosystems. We computed annual low-flow period duration and timing metrics from 1951 to 2020 for 1032 conterminous United States (CONUS) streamgages and analyzed spatial patterns, trends through time, and relationships to climate. Results show northwestern...
Authors
Caelan Simeone, Gregory McCabe, Jory Hecht, John C. Hammond, Glenn Hodgkins, Carolyn Olson, Michael Wieczorek, David Wolock
A hydrologic perspective of major U.S. droughts A hydrologic perspective of major U.S. droughts
Drought is a recurring natural hazard that has substantial human and environmental impacts. Given continued global warming and associated climate change, there is concern that droughts could become more severe and longer lasting. To better monitor and understand drought development and persistence, it is helpful to understand the development and climatic drivers of past droughts. In this...
Authors
Gregory McCabe, David Wolock, Melissa Lombard, Robert Dudley, John Hammond, Jory Hecht, Glenn Hodgkins, Carolyn Olson, Roy Sando, Caelan Simeone, Michael Wieczorek
Going beyond low flows: Streamflow drought deficit and duration illuminate distinct spatiotemporal drought patterns and trends in the U.S. during the last century Going beyond low flows: Streamflow drought deficit and duration illuminate distinct spatiotemporal drought patterns and trends in the U.S. during the last century
Streamflow drought is a recurring challenge, and understanding spatiotemporal patterns of past droughts is needed to manage future water resources. We examined regional patterns in streamflow drought metrics and compared these metrics to low flow timing and magnitude using long-term daily records for 555 minimally disturbed watersheds. For each streamgage, we calculated streamflow...
Authors
John C. Hammond, Caelan Simeone, Jory Hecht, Glenn Hodgkins, Melissa Lombard, Gregory McCabe, David Wolock, Michael Wieczorek, Carolyn G Olson, Todd Caldwell, Robert W. Dudley, Adam Price
Tree rings reveal unmatched 2nd century drought in the Colorado River Basin Tree rings reveal unmatched 2nd century drought in the Colorado River Basin
The ongoing 22 year drought in the Upper Colorado River Basin (UCRB) has been extremely severe, even in the context of the longest available tree-ring reconstruction of annual flow at Lees Ferry, Arizona, dating back to 762 CE. While many southwestern drought assessments have been limited to the past 1200 years, longer paleorecords of moisture variability do exist for the UCRB. Here...
Authors
Subhrendu Gangopadhyay, Connie Woodhouse, Gregory McCabe, Cody Routson, David Meko
Extensive droughts in the conterminous United States during multiple centuries Extensive droughts in the conterminous United States during multiple centuries
Extensive and severe droughts have substantial effects on water supplies, agriculture, and aquatic ecosystems. To better understand these droughts, we used tree-ring-based reconstructions of the Palmer drought severity index (PDSI) for the period 1475–2017 to examine droughts that covered at least 33% of the conterminous United States (CONUS). We identified 37 spatially extensive drought...
Authors
Gregory McCabe, David Wolock
Drought is a prolonged and widespread deficit in available water supplies that creates multiple stressors across ecosystems and communities. The U.S. Geological Survey Water Mission Area conducts drought research and modeling to improve drought prediction capabilities. The research focus is on understanding the hydrological, ecological, and economic ramifications of drought. The modeling focus builds on the research to provide predictive capacity for resilience planning at local, regional, and national levels. Prediction of the onset, severity, and duration of hydrologic drought conditions is critical for the USGS to identify and evaluate multi-sector responses to alterations in water availability.
The U.S. Geological Survey drought prediction science capacity includes monitoring, research, and modeling. Long-term water monitoring has allowed for identification of drought periods in the context of climatic variability and change, and for statistical trend analysis of continuous data to support earlier and more accurate detection of low-flow and drought conditions. Recent drought science research has focused on modeling and analysis of drivers of hydrologic drought.
In addition, the U.S. Geological Survey is exploring the usage of new data-driven methods (artificial intelligence and machine learning) to predict and deliver early warning of hydrological drought conditions at higher spatial and temporal resolution than currently available. These data-driven drought prediction models will provide useful information to stakeholders on drought onset, duration, and severity metrics (and their uncertainty) for surface water and groundwater.
Ongoing scientific inquiries and activities to support drought characterization and prediction include:
- Supporting the assimilation, screening, analysis, publication, archiving, and delivery of drought data from USGS and other sources;
- Developing stakeholder-relevant hydrologic drought metrics;
- Describing uncertainties associated with drought causes and effects;
- Incorporating the drivers of flash drought into predictive modeling;
- Establishing links between the effects of drought on wildfire, floods, and water quality; and,
- Developing regional- and national-scale prototype maps that will display streamflow drought conditions as well as predictions for weeks to months in advance.
Highlighted Publications
- Simeone, C., Foks, S., Towler, E., Hodson, T., and Over, T. (2024) Evaluating hydrologic model performance for characterizing streamflow drought in the conterminous United States. Water, 16, 2996. DOI: 10.3390/w16202996
- Simeone, C., Hammond, J., Archfield, S.A., Broman, D., Condon, L.E., Eldardiry, H., Olson, C.G., and Steyaert, J.C. (2024) Declining Reservoir Reliability and Increasing Reservoir Vulnerability: Long-Term Observations Reveal Longer and More Severe Periods of Low Reservoir Storage for Major United States Reservoirs. Geophysical Research Letters, 51, e2024GL109476. DOI: 10.1029/2024GL109476
Data releases related to U.S. Geological Survey drought prediction science.
Model inputs for machine learning models forecasting streamflow drought across the conterminous United States (ver. 2.0, September 2025) Model inputs for machine learning models forecasting streamflow drought across the conterminous United States (ver. 2.0, September 2025)
This dataset contains 3,229 feather files with time series of all model inputs for machine learning models predicting streamflow drought across the conterminous United States (CONUS). Files contain weekly time series of streamflow percentiles, meteorology, snow water equivalent, forecast meteorology, estimated water use, soil moisture, as well as lagged versions of these datasets. Values...
Metrics to Characterizing Periods of Anomalously Low Water Storage for Selected Reservoirs in the Conterminous U.S. from 1981 to 2020 Metrics to Characterizing Periods of Anomalously Low Water Storage for Selected Reservoirs in the Conterminous U.S. from 1981 to 2020
This metadata record describes a series of tabular datasets containing metrics used to characterize periods of anomalously low storage for select large reservoirs across the Conterminous United States for the climate years (April 1 – March 31) from 1981 to 2020. These data support the associated Simeone and others (2024) publication. The reservoirs in this dataset are those included in...
Low-Flow Period Seasonality, Trends, and Climate Linkages Across the United States Data Release Low-Flow Period Seasonality, Trends, and Climate Linkages Across the United States Data Release
This metadata record describes data that characterize low-flow period duration and seasonality, as well as trends and climate linkages at streamgages across the conterminous United States. These data are associated with a publication which looks to answer three questions about low-flow periods in the conterminous United States: (1) how long are these periods and when do they typically...
Data-Driven Drought Prediction Project Model Outputs for Select Spatial Units within the Conterminous United States Data-Driven Drought Prediction Project Model Outputs for Select Spatial Units within the Conterminous United States
This metadata record describes model outputs and supporting model code for the Data-Driven Drought Prediction project of the Water Resources Mission Area Drought Program. The data listed here include outputs of multiple machine learning model types for predicting hydrological drought at select locations within the conterminous United States. The child items referenced below correspond to...
Data-Driven Drought Prediction Project Model Inputs for Upper and Lower Colorado Portions of the National Hydrologic Geo-Spatial Fabric version 1.1 and Select U.S. Geological Survey Streamgage Basins (ver. 2.0, July 2025) Data-Driven Drought Prediction Project Model Inputs for Upper and Lower Colorado Portions of the National Hydrologic Geo-Spatial Fabric version 1.1 and Select U.S. Geological Survey Streamgage Basins (ver. 2.0, July 2025)
This metadata record describes a series of data sets of natural, climatic, and anthropogenic landscape features processed as model inputs for the Data-Driven Drought Prediction Project of the Water Resources Mission Area Drought Program. These data are linked to two different spatial units: the National Hydrologic Geospatial Fabric version 1.1 (nhgfv1.1) including their associated...
Streamflow Drought Metrics for Select United States Geological Survey Streamgages for Three Different Time Periods from 1921 - 2020 Streamflow Drought Metrics for Select United States Geological Survey Streamgages for Three Different Time Periods from 1921 - 2020
This metadata record describes a series of datasets containing metrics used to characterize drought for four sets of United States Geological Survey (USGS) streamgages in the conterminous United States (CONUS) for three different time periods between 1921 and 2020 outlined below. The streamgages used are a subset based on the criteria used in Geospatial Attributes of Gages for Evaluating...
U.S. Streamflow Drought During the Last Century: annual drought and low flow metrics, annual climate, and trends for the periods 1921-, 1951- and 1981-2020 (ver. 1.1, August 2025) U.S. Streamflow Drought During the Last Century: annual drought and low flow metrics, annual climate, and trends for the periods 1921-, 1951- and 1981-2020 (ver. 1.1, August 2025)
This dataset contains annual flow metrics quantifying drought and low streamflows for USGS GAGES-2 gages in the contiguous U.S. satisfying data completeness checks for the periods 1921-2020, 1951-2020, and 1981-2020. The dataset also contains annual climate variables from the USGS Monthly Water Balance Model (MWBM). The dataset provides trend analysis outputs for annual drought and low...
USGS monthly water balance model inputs and outputs for the conterminous United States, 1895-2020, based on ClimGrid data USGS monthly water balance model inputs and outputs for the conterminous United States, 1895-2020, based on ClimGrid data
This NetCDF represents the monthly inputs and outputs from a United States Geological Survey water-balance model (McCabe and Wolock, 2011) for the conterminous United States for the period 1895-01-01 to 2020-12-31. The source data used to run the water balance model is based on the National Oceanic and Atmospheric Administration's(NOAA, 2020) ClimGrid data for precipitation and...
Clusters of monthly streamflow values with similar temporal patterns at 555 HCDN sites for the period 1981 to 2019 Clusters of monthly streamflow values with similar temporal patterns at 555 HCDN sites for the period 1981 to 2019
This data release identifies 555 Hydro-Climatic Data Network (HCDN) streamgages in the conterminous United States during the period 1981-2019 which were grouped according to similarity in their temporal patterns of monthly streamflow.
Publications related to U.S. Geological Survey drought prediction science.
Hydrological whiplash: Highlighting the need for better understanding and quantification of sub-seasonal hydrological extreme transitions Hydrological whiplash: Highlighting the need for better understanding and quantification of sub-seasonal hydrological extreme transitions
In this commentary, we aim to (1) describe ways that hydrological intensification and hydrological whiplash (sub-seasonal transitions between hydrological extremes) may impact water management decision-making, (2) introduce the complexities of identifying and quantifying hydrological extreme transitions, (3) discuss the processes controlling hydrological transitions and trends in...
Authors
John C. Hammond, Bailey Anderson, Caelan Simeone, Manuela Brunner, Eduardo Munoz-Castro, Stacey Archfield, Eugene Magee, Rachael Armitage
Evaluating hydrologic model performance for characterizing streamflow drought in the conterminous United States Evaluating hydrologic model performance for characterizing streamflow drought in the conterminous United States
Hydrologic models are the primary tools that are used to simulate streamflow drought and assess impacts. However, there is little consensus about how to evaluate the performance of these models, especially as hydrologic modeling moves toward larger spatial domains. This paper presents a comprehensive multi-objective approach to systematically evaluating the critical features in...
Authors
Caelan Simeone, Sydney Foks, Erin Towler, Timothy Hodson, Thomas Over
Agricultural tile drains increase the susceptibility of streams to longer and more intense streamflow droughts Agricultural tile drains increase the susceptibility of streams to longer and more intense streamflow droughts
Streamflow droughts are receiving increased attention worldwide due to their impact on the environment and economy. One region of concern is the Midwestern United States, whose agricultural productivity depends on subsurface pipes known as tile drains to improve trafficability and soil conditions for crop growth. Tile drains accomplish this by rapidly transporting surplus soil moisture...
Authors
Seth Adelsperger, Darren Ficklin, Scott Robeson, Margaret Zimmer, John C. Hammond, Damon Hall, J.P. Gannon
Streamflow timing and magnitude during snow drought depend on snow drought type and regional hydroclimate Streamflow timing and magnitude during snow drought depend on snow drought type and regional hydroclimate
Communities around the world rely on snowmelt to meet water demands, and periods of lower than normal snow accumulation, snow droughts, can decrease water supplies. Leveraging 172 minimally disturbed and seasonally snow-covered watersheds, we developed an approach to examine the effects of cool & dry, warm & dry, and warm & wet snow droughts on streamflow timing and magnitude by...
Authors
John C. Hammond, Annie Putman, Theodore B. Barnhart, Graham A. Sexstone, Gregory McCabe, David Wolock, Aaron Heldmyer, Stephanie Kampf
Declining reservoir reliability and increasing reservoir vulnerability: Long-term observations reveal longer and more severe periods of low reservoir storage for major United States reservoirs Declining reservoir reliability and increasing reservoir vulnerability: Long-term observations reveal longer and more severe periods of low reservoir storage for major United States reservoirs
Hydrological drought is a pervasive and reoccurring challenge in managing water resources. Reservoirs are critical for lessening the impacts of drought on water available for many uses. We use a novel and generalized approach to identify periods of unusually low reservoir storage—via comparisons to operational rule curves and historical patterns—to investigate how droughts affect storage...
Authors
Caelan Simeone, John C. Hammond, Stacey Archfield, Dan Broman, Laura Condon, Hisham Eldardiry, Carolyn Olson, Jen Steyaert
Low-flow period seasonality, trends, and climate linkages across the United States Low-flow period seasonality, trends, and climate linkages across the United States
Low-flow period properties, including timing, magnitude, and duration, influence many key processes for water resource managers and ecosystems. We computed annual low-flow period duration and timing metrics from 1951 to 2020 for 1032 conterminous United States (CONUS) streamgages and analyzed spatial patterns, trends through time, and relationships to climate. Results show northwestern...
Authors
Caelan Simeone, Gregory McCabe, Jory Hecht, John C. Hammond, Glenn Hodgkins, Carolyn Olson, Michael Wieczorek, David Wolock
A hydrologic perspective of major U.S. droughts A hydrologic perspective of major U.S. droughts
Drought is a recurring natural hazard that has substantial human and environmental impacts. Given continued global warming and associated climate change, there is concern that droughts could become more severe and longer lasting. To better monitor and understand drought development and persistence, it is helpful to understand the development and climatic drivers of past droughts. In this...
Authors
Gregory McCabe, David Wolock, Melissa Lombard, Robert Dudley, John Hammond, Jory Hecht, Glenn Hodgkins, Carolyn Olson, Roy Sando, Caelan Simeone, Michael Wieczorek
Going beyond low flows: Streamflow drought deficit and duration illuminate distinct spatiotemporal drought patterns and trends in the U.S. during the last century Going beyond low flows: Streamflow drought deficit and duration illuminate distinct spatiotemporal drought patterns and trends in the U.S. during the last century
Streamflow drought is a recurring challenge, and understanding spatiotemporal patterns of past droughts is needed to manage future water resources. We examined regional patterns in streamflow drought metrics and compared these metrics to low flow timing and magnitude using long-term daily records for 555 minimally disturbed watersheds. For each streamgage, we calculated streamflow...
Authors
John C. Hammond, Caelan Simeone, Jory Hecht, Glenn Hodgkins, Melissa Lombard, Gregory McCabe, David Wolock, Michael Wieczorek, Carolyn G Olson, Todd Caldwell, Robert W. Dudley, Adam Price
Tree rings reveal unmatched 2nd century drought in the Colorado River Basin Tree rings reveal unmatched 2nd century drought in the Colorado River Basin
The ongoing 22 year drought in the Upper Colorado River Basin (UCRB) has been extremely severe, even in the context of the longest available tree-ring reconstruction of annual flow at Lees Ferry, Arizona, dating back to 762 CE. While many southwestern drought assessments have been limited to the past 1200 years, longer paleorecords of moisture variability do exist for the UCRB. Here...
Authors
Subhrendu Gangopadhyay, Connie Woodhouse, Gregory McCabe, Cody Routson, David Meko
Extensive droughts in the conterminous United States during multiple centuries Extensive droughts in the conterminous United States during multiple centuries
Extensive and severe droughts have substantial effects on water supplies, agriculture, and aquatic ecosystems. To better understand these droughts, we used tree-ring-based reconstructions of the Palmer drought severity index (PDSI) for the period 1475–2017 to examine droughts that covered at least 33% of the conterminous United States (CONUS). We identified 37 spatially extensive drought...
Authors
Gregory McCabe, David Wolock