Increased drought severity tracks warming in the United States’ largest river basin

Across the Upper Missouri River Basin, the recent drought of 2000 to 2010, known as the “turn-of-the-century drought,” was likely more severe than any in the instrumental record including the Dust Bowl drought. However, until now, adequate proxy records needed to better understand this event with regard to long-term variability have been lacking. Here we examine 1,200 y of streamflow from a network of 17 new tree-ring–based reconstructions for gages across the upper Missouri basin and an independent reconstruction of warm-season regional temperature in order to place the recent drought in a long-term climate context. We find that temperature has increasingly influenced the severity of drought events by decreasing runoff efficiency in the basin since the late 20th century (1980s) onward. The occurrence of extreme heat, higher evapotranspiration, and associated low-flow conditions across the basin has increased substantially over the 20th and 21st centuries, and recent warming aligns with increasing drought severities that rival or exceed any estimated over the last 12 centuries. Future warming is anticipated to cause increasingly severe droughts by enhancing water deficits that could prove challenging for water management.

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Prototyping a Methodology for Long-Term (1680–2100) Historical-to-Future Landscape Modeling for the Conterminous United States

Land ◽

10.3390/land10050536 ◽

2021 ◽

Vol 10 (5) ◽

pp. 536

Author(s):

Jordan Dornbierer ◽

Steve Wika ◽

Charles Robison ◽

Gregory Rouze ◽

Terry Sohl

Keyword(s):

United States ◽

Land Cover ◽

River Basin ◽

Landscape Change ◽

Spatial Scales ◽

The United States ◽

Modeling Framework ◽

Delaware River ◽

Future Landscape

Land system change has been identified as one of four major Earth system processes where change has passed a destabilizing threshold. A historical record of landscape change is required to understand the impacts change has had on human and natural systems, while scenarios of future landscape change are required to facilitate planning and mitigation efforts. A methodology for modeling long-term historical and future landscape change was applied in the Delaware River Basin of the United States. A parcel-based modeling framework was used to reconstruct historical landscapes back to 1680, parameterized with a variety of spatial and nonspatial historical datasets. Similarly, scenarios of future landscape change were modeled for multiple scenarios out to 2100. Results demonstrate the ability to represent historical land cover proportions and general patterns at broad spatial scales and model multiple potential future landscape trajectories. The resulting land cover collection provides consistent data from 1680 through 2100, at a 30-m spatial resolution, 10-year intervals, and high thematic resolution. The data are consistent with the spatial and thematic characteristics of widely used national-scale land cover datasets, facilitating use within existing land management and research workflows. The methodology demonstrated in the Delaware River Basin is extensible and scalable, with potential applications at national scales for the United States.

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Assessment of Drought Severity and Vulnerability in the Lam Phaniang River Basin, Thailand

Water ◽

10.3390/w13192743 ◽

2021 ◽

Vol 13 (19) ◽

pp. 2743

Author(s):

Kittiwet Kuntiyawichai ◽

Sarayut Wongsasri

Keyword(s):

River Basin ◽

Time Scales ◽

Water Demand ◽

Water Shortage ◽

Risk Level ◽

Drought Severity ◽

Drought Risk ◽

Drought Vulnerability ◽

Rcp 8.5

The Lam Phaniang River Basin is one of the areas in Northeast Thailand that experiences persistent drought almost every year. Therefore, this study was focused on the assessment of drought severity and vulnerability in the Lam Phaniang River Basin. The evaluation of drought severity was based on the Drought Hazard Index (DHI), which was derived from the Standardized Precipitation-Evapotranspiration Index (SPEI) calculated for 3-month (short-term), 12-month (intermediate-term), and 24-month (long-term) periods. Drought vulnerability was assessed by the Drought Vulnerability Index (DVI), which relied on water shortage, water demand, and runoff calculated from the WEAP model, and the Gross Provincial Product (GPP) data. A drought risk map was generated by multiplying the DHI and DVI indices, and the drought risk level was then defined afterwards. The CNRM-CM5, EC-EARTH, and NorESM1-M global climate simulations, and the TerrSet software were used to evaluate the potential impacts of future climate under RCPs 4.5 and 8.5, and land use during 2021–2100, respectively. The main findings compared to baseline (2000–2017) revealed that the average results of future rainfall, and maximum and minimum temperatures were expected to increase by 1.41 mm, and 0.015 °C/year and 0.019 °C/year, respectively, under RCP 4.5 and by 2.72 mm, and 0.034 °C/year and 0.044 °C/year, respectively, under RCP 8.5. During 2061–2080 under RCP 8.5, the future annual water demand and water shortage were projected to decrease by a maximum of 31.81% and 51.61%, respectively. Obviously, in the Lam Phaniang River Basin, the upper and lower parts were mainly dominated by low and moderate drought risk levels at all time scales under RCPs 4.5 and 8.5. Focusing on the central part, from 2021–2040, a very high risk of intermediate- and long-term droughts under RCPs 4.5 and 8.5 dominated, and occurred under RCP 8.5 from 2041–2060. From 2061 to 2080, at all time scales, the highest risk was identified under RCP 4.5, while low and moderate levels were found under RCP 8.5. From 2081–2100, the central region was found to be at low and moderate risk at all time scales under RCPs 4.5 and 8.5. Eventually, the obtained findings will enable stakeholders to formulate better proactive drought monitoring, so that preparedness, adaptation, and resilience to droughts can be strengthened.

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Genomic analyses of Northern snakehead (Channa argus) populations in North America

PeerJ ◽

10.7717/peerj.4581 ◽

2018 ◽

Vol 6 ◽

pp. e4581 ◽

Cited By ~ 3

Author(s):

Carlee A. Resh ◽

Matthew P. Galaska ◽

Andrew R. Mahon

Keyword(s):

United States ◽

Invasive Species ◽

River Basin ◽

Hudson River ◽

The United States ◽

Aquatic Invasive Species ◽

Potomac River ◽

Potomac River Basin ◽

Channa Argus

Background The introduction of northern snakehead (Channa argus; Anabantiformes: Channidae) and their subsequent expansion is one of many problematic biological invasions in the United States. This harmful aquatic invasive species has become established in various parts of the eastern United States, including the Potomac River basin, and has recently become established in the Mississippi River basin in Arkansas. Effective management of C. argus and prevention of its further spread depends upon knowledge of current population structure in the United States. Methods Novel methods for invasive species using whole genomic scans provide unprecedented levels of data, which are able to investigate fine scale differences between and within populations of organisms. In this study, we utilize 2b-RAD genomic sequencing to recover 1,007 single-nucleotide polymorphism (SNP) loci from genomic DNA extracted from 165 C. argus individuals: 147 individuals sampled along the East Coast of the United States and 18 individuals sampled throughout Arkansas. Results Analysis of those SNP loci help to resolve existing population structure and recover five genetically distinct populations of C. argus in the United States. Additionally, information from the SNP loci enable us to begin to calculate the long-term effective population size ranges of this harmful aquatic invasive species. We estimate long-term Ne to be 1,840,000–18,400,000 for the Upper Hudson River basin, 4,537,500–45,375,000 for the Lower Hudson River basin, 3,422,500–34,225,000 for the Potomac River basin, 2,715,000–7,150,000 for Philadelphia, and 2,580,000–25,800,000 for Arkansas populations. Discussion and Conclusions This work provides evidence for the presence of more genetic populations than previously estimated and estimates population size, showing the invasive potential of C. argus in the United States. The valuable information gained from this study will allow effective management of the existing populations to avoid expansion and possibly enable future eradication efforts.

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A national cohort study (2000–2018) of long-term air pollution exposure and incident dementia in older adults in the United States

Nature Communications ◽

10.1038/s41467-021-27049-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Liuhua Shi ◽

Kyle Steenland ◽

Haomin Li ◽

Pengfei Liu ◽

Yuhan Zhang ◽

...

Keyword(s):

Air Pollution ◽

Fine Particulate Matter ◽

Warm Season ◽

The United States ◽

Population Based ◽

Hazard Ratios ◽

Incident Dementia ◽

Increase Risk ◽

National Cohort

AbstractAir pollution may increase risk of Alzheimer’s disease and related dementias (ADRD) in the U.S., but the extent of this relationship is unclear. Here, we constructed two national U.S. population-based cohorts of those aged ≥65 from the Medicare Chronic Conditions Warehouse (2000–2018), combined with high-resolution air pollution datasets, to investigate the association of long-term exposure to ambient fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3) with dementia and AD incidence, respectively. We identified ~2.0 million incident dementia cases (N = 12,233,371; dementia cohort) and ~0.8 million incident AD cases (N = 12,456,447; AD cohort). Per interquartile range (IQR) increase in the 5-year average PM2.5 (3.2 µg/m3), NO2 (11.6 ppb), and warm-season O3 (5.3 ppb) over the past 5 years prior to diagnosis, the hazard ratios (HRs) were 1.060 (95% confidence interval [CI]: 1.054, 1.066), 1.019 (95% CI: 1.012, 1.026), and 0.990 (95% CI: 0.987, 0.993) for incident dementias, and 1.078 (95% CI: 1.070, 1.086), 1.031 (95% CI: 1.023, 1.039), and 0.982 (95%CI: 0.977, 0.986) for incident AD, respectively, for the three pollutants. For both outcomes, concentration-response relationships for PM2.5 and NO2 were approximately linear. Our study suggests that exposures to PM2.5 and NO2 are associated with incidence of dementia and AD.

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Paleohydrological context for recent floods and droughts in the Fraser River Basin, British Columbia, Canada

Environmental Research Letters ◽

10.1088/1748-9326/ac3daf ◽

2021 ◽

Author(s):

Becky L. Brice ◽

Bethany Lynn Coulthard ◽

Inga K. Homfeld ◽

Laura Dye ◽

Kevin J. Anchukaitis

Keyword(s):

British Columbia ◽

River Basin ◽

Fraser River ◽

Proxy Records ◽

Target Management ◽

Floods And Droughts ◽

High Flood ◽

Cultural Ecological ◽

Observational Record

Abstract The recent intensification of floods and droughts in the Fraser River Basin of British Columbia has had profound cultural, ecological, and economic impacts that are expected to be exacerbated further by anthropogenic climate change. In part due to short instrumental runoff records, the long-term stationarity of hydroclimatic extremes in this major North American watershed remains poorly understood, highlighting the need to use high-resolution paleoenvironmental proxies to inform on past streamflow. Here we use a network of tree-ring proxy records to develop 11 subbasin-scale, complementary flood- and drought-season reconstructions, the first of their kind. The reconstructions explicitly target management-relevant flood and drought seasons within each basin, and are examined in tandem to provide an expanded assessment of extreme events across the Fraser River Basin with immediate implications for water management. We find that past high flood-season flows have been of greater magnitude and occurred in more consecutive years than during the observational record alone. Early 20th century low flows in the drought season were especially severe in both duration and magnitude in some subbasins relative to recent dry periods. Our Fraser subbasin-scale reconstructions provide long-term benchmarks for the natural flood and drought variability prior to anthropogenic forcing. These reconstructions demonstrate that the instrumental streamflow records upon which current management is based likely underestimate the full natural magnitude, duration, and frequency of extreme seasonal flows in the Fraser River Basin, as well as the potential severity of future anthropogenically forced events.

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Drought and flood characterization and connection to climate variability in Pearl River Basin, Southern China using long-term GRACE and reanalysis data

Journal of Climate ◽

10.1175/jcli-d-20-0332.1 ◽

2020 ◽

pp. 1-63

Author(s):

Zhiyong Huang ◽

Jiu Jimmy Jiao ◽

Xin Luo ◽

Yun Pan ◽

Taoyong Jin

Keyword(s):

River Basin ◽

Southern Oscillation ◽

Southern China ◽

Water Storage ◽

Reanalysis Data ◽

Pearl River ◽

Drought Severity ◽

Pearl River Basin ◽

Drought And Flood

Abstract:This study investigates drought and flood in the Pearl River Basin using long-term terrestrial water storage anomaly (TWSA) data from the mascon solutions based on the Gravity Recovery And Climate Experiment (GRACE) satellite measurements (2002-2019) and the reanalysis data (1980-2019). To characterize drought, water storage deficit (WSD) and WSD index are used. The GRACE mascon solutions capture two major drought periods (2003-2006, 2009-2012) with similar onsets and endings over the last two decades, but show considerable differences in quantifying total drought severity. The reanalysis data significantly overestimates drought duration and severity during 1980-2000 owing to underestimated TWSA forced by incorrect precipitation data. Flood is monitored using a flood potential index (FPI) calculated using TWSA and precipitation. The GRACE mascon solutions identify four major flood events (FPI > 0.7) in Aug. 2002, Jun. 2008, and Jul. in 2006 and 2019. The flood potential is influenced by the precipitation in both the current and antecedent months. The spatial variability of the most recent flood in 2008 is analyzed, showing a similar spatial pattern between FPI and precipitation at monthly and sub-basin scales. The precipitation/TWSA in the PRB is mainly influenced by El Niño–Southern Oscillation (ENSO). TWSA exhibits a lag of 1-3 months responding to ENSO during 1980-2019. This study emphasizes the significance of removing water storage changes in large reservoirs before long-term drought, flood characterization and teleconnection analysis. This study highlights the intensifying drought conditions in the PRB over the last four decades under the circumstances of more frequent human activities (reservoir construction and regulation) and the complex changing climate system.

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Evaluation of low-flow metrics as environmental instream flow standards during long-term average and 2016 drought conditions: Tombigbee River Basin, Alabama and Mississippi, USA

Water Policy ◽

10.2166/wp.2018.023 ◽

2018 ◽

Vol 20 (6) ◽

pp. 1240-1255 ◽

Cited By ~ 2

Author(s):

Sarah Praskievicz ◽

Cehong Luo ◽

Bennett Bearden ◽

Andrew Ernest

Keyword(s):

River Basin ◽

Environmental Flow ◽

Low Flow ◽

Instream Flow ◽

Management Actions ◽

Instream Flows ◽

Societal Needs ◽

Drought Conditions ◽

Historical Flow

Abstract Environmental instream flows are a common tool for maintaining river flows that are required to sustain both ecosystem and societal needs. Many of the most widely adopted environmental flow standards are based on historical flow, mainly because of the relative simplicity of these methods. Few previous studies, however, have examined the ability of historical flow standards to protect low flows. Here, the low-flow protective ability of five different historical flow methods, using 35 gaging stations in the Tombigbee River Basin of Alabama and Mississippi, was analyzed. The minimum environmental flow thresholds were calculated using the five indices, and the number of times in a recent 32-year period flows fell below each threshold was determined. The Tennant-based threshold was reached most frequently, followed by the modified Tennant. Although other low-flow metrics, such as 7Q10, were triggered infrequently (9% of the time) over the whole period, triggering rates increased to 46% for 7Q10 during the drought of 2016, suggesting that even minimal low-flow standards may provide some benefit during drought. Analyzing historical flow methods to see how often they would result in management actions if implemented is a useful way of developing guidance on the adoption of minimum environmental instream flow standards.

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Multi-year objective analyses of warm season ground-level ozone and PM<sub>2.5</sub> over North America using real-time observations and Canadian operational air quality models

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-1769-2014 ◽

2014 ◽

Vol 14 (4) ◽

pp. 1769-1800 ◽

Cited By ~ 59

Author(s):

A. Robichaud ◽

R. Ménard

Keyword(s):

Air Quality ◽

North America ◽

Warm Season ◽

Ground Level ◽

The United States ◽

Error Statistics ◽

Spatiotemporal Resolution ◽

Ground Level Ozone ◽

Air Quality Forecast

Abstract. Multi-year objective analyses (OA) on a high spatiotemporal resolution for the warm season period (1 May to 31 October) for ground-level ozone and for fine particulate matter (diameter less than 2.5 microns (PM2.5)) are presented. The OA used in this study combines model outputs from the Canadian air quality forecast suite with US and Canadian observations from various air quality surface monitoring networks. The analyses are based on an optimal interpolation (OI) with capabilities for adaptive error statistics for ozone and PM2.5 and an explicit bias correction scheme for the PM2.5 analyses. The estimation of error statistics has been computed using a modified version of the Hollingsworth–Lönnberg (H–L) method. The error statistics are "tuned" using a χ2 (chi-square) diagnostic, a semi-empirical procedure that provides significantly better verification than without tuning. Successful cross-validation experiments were performed with an OA setup using 90% of data observations to build the objective analyses and with the remainder left out as an independent set of data for verification purposes. Furthermore, comparisons with other external sources of information (global models and PM2.5 satellite surface-derived or ground-based measurements) show reasonable agreement. The multi-year analyses obtained provide relatively high precision with an absolute yearly averaged systematic error of less than 0.6 ppbv (parts per billion by volume) and 0.7 μg m−3 (micrograms per cubic meter) for ozone and PM2.5, respectively, and a random error generally less than 9 ppbv for ozone and under 12 μg m−3 for PM2.5. This paper focuses on two applications: (1) presenting long-term averages of OA and analysis increments as a form of summer climatology; and (2) analyzing long-term (decadal) trends and inter-annual fluctuations using OA outputs. The results show that high percentiles of ozone and PM2.5 were both following a general decreasing trend in North America, with the eastern part of the United States showing the most widespread decrease, likely due to more effective pollution controls. Some locations, however, exhibited an increasing trend in the mean ozone and PM2.5, such as the northwestern part of North America (northwest US and Alberta). Conversely, the low percentiles are generally rising for ozone, which may be linked to the intercontinental transport of increased emissions from emerging countries. After removing the decadal trend, the inter-annual fluctuations of the high percentiles are largely explained by the temperature fluctuations for ozone and to a lesser extent by precipitation fluctuations for PM2.5. More interesting is the economic short-term change (as expressed by the variation of the US gross domestic product growth rate), which explains 37% of the total variance of inter-annual fluctuations of PM2.5 and 15% in the case of ozone.

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Using Long-term Capture Data to Predict Trogoderma variabile Ballion and Plodia interpunctella (Hübner) Population Patterns

Insects ◽

10.3390/insects10040093 ◽

2019 ◽

Vol 10 (4) ◽

pp. 93 ◽

Cited By ~ 3

Author(s):

Alison Gerken ◽

James Campbell

Keyword(s):

Pest Management ◽

Warm Season ◽

Plodia Interpunctella ◽

The United States ◽

Management Program ◽

Seasonal Patterns ◽

Flour Mill ◽

Trogoderma Variabile ◽

Management Tactics

Insects can infest facilities that house and process post-harvest grains and grain-based products. Integrated pest management tactics rely on tracking insect populations and using this information to select and target management tactics. Our ability to predict when and where to best focus treatment relies on an understanding of long-term trends, but often any available monitoring data are limited in its duration. Here we present data collected over a 10-year period at a flour mill in the central part of the United States. Using traps placed both inside and outside a flour mill and baited with pheromone-lures for Plodia interpunctella (Hübner), Indianmeal moth, and Trogoderma variabile Ballion, warehouse beetle, we examine environmental and spatial variability in insect captures. We find that both species, inside and outside the mill, are highly influenced by seasonal patterns, with peaks of insect captures during the warm season (April through September). There is also consistency across time and space in trap capture for P. interpunctella with traps in an open location consistently capturing high numbers of insects. In contrast, T. variabile lacked consistency in trap capture but were most often not found in the same trap locations as P. interpunctella. Fumigations conducted within the facility appeared to have little impact on insect captures inside, with dynamics appearing to be driven more by broader seasonal patterns in activity. These data and analyses suggest that there is a larger population of these insects that are readily moving in and out of the structures, while fumigation treatments are only impacting a small portion of the overall population and tactics targeting immigration may be an important addition to the pest management program.

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Drought Assessment by a Short-/Long-Term Composited Drought Index in the Upper Huaihe River Basin, China

Advances in Meteorology ◽

10.1155/2016/7986568 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Meixiu Yu ◽

Xiaolong Liu ◽

Li Wei ◽

Qiongfang Li ◽

Jianyun Zhang ◽

...

Keyword(s):

River Basin ◽

Drought Index ◽

Drought Monitoring ◽

Drought Indices ◽

Drought Severity ◽

Huaihe River Basin ◽

Huaihe River ◽

Short Term ◽

Drought Assessment

Accurate and reliable drought monitoring is of primary importance for drought mitigation and reduction of social-ecological vulnerability. The aim of the paper was to propose a multiscale composited drought index (CDI) which could be widely used for drought monitoring and early warning in China. In the study, the upper Huaihe River basin above the Xixian gauge station, which has been hit by severe droughts frequently in recent decades, was selected as the case study site. The newly built short-term/long-term CDI comprehensively considered three natural forms of drought (meteorological, hydrological, and agricultural) by selection of different variables that are related to each drought type. The short-term/long-term CDI was developed using the Principle Component Analysis of related drought components. The thresholds of the short-term/long-term CDI were determined according to frequency statistics of different drought indices. Finally, the feasibility of the two CDI was investigated against the self-calibrating Palmer drought severity index, the standardized precipitation evapotranspiration index, and the historical drought records. The results revealed that the short-term/long-term CDI could capture the onset, severity, and persistence of drought events very well with the former being better at identifying the dynamic evolution of drought condition and the latter better at judging the changing trend of drought over a long time period.

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