Considering Streamflow Trend Analyses Uncertainty in Urbanizing Watersheds: A Baseflow Case Study in the Central United States

Abstract Assuming pro rata reductions in baseflow resulting from urban development may not be valid in all urbanizing watersheds. Anthropogenic offsets or compensatory contributions to baseflow (e.g., net exfiltration from sewer lines, wastewater effluents, and lawn irrigation) may mask or confound fundamental changes in hydrologic pathways. These offsets illustrate the complexities of urban flow processes and the need for improved understanding to mitigate urban development impacts. The authors used two dissimilar automated baseflow separation algorithms and Monte Carlo techniques to evaluate urban baseflow and estimation uncertainty using data from a representative urban watershed in the central United States. Three uncertainties affecting trend determinations were assessed, including algorithm structure, precipitation–runoff relationships, and baseflow algorithm parameterization. Results indicate that, despite ongoing population growth and development, annual streamflow metrics in the authors' representative watershed have not significantly increased or decreased (p > 0.05) from 1967 to 2010. However, several streamflow metrics featured shallow insignificant (p > 0.05) slopes in the direction hypothesized for an urbanizing (less pervious) watershed, including a downward slope for baseflow index (BFI) and increases in runoff volume coefficient. Median annual baseflow estimations differed by 29% between techniques (85.3 versus 118.9 mm yr−1). In the absence of direct tracer measurements, uncertainties associated with precipitation–runoff relationships, algorithm structure, and parameterization should be included in analyses evaluating alterations from baseline hydrologic conditions in urban watersheds. To advance application of separation algorithms for urban watersheds and support regulatory reductions in runoff volume, future work should include calibration of model parameters to available hydrogeologic and tracer data.

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Spatial attenuation of intensities for central U.S. earthquakes

Bulletin of the Seismological Society of America ◽

10.1785/bssa0660030743 ◽

1976 ◽

Vol 66 (3) ◽

pp. 743-751

Author(s):

Indra N. Gupta ◽

Otto W. Nuttli

Keyword(s):

United States ◽

Ground Motion ◽

Epicentral Distance ◽

Near Field ◽

Mississippi Valley ◽

Average Value ◽

Anelastic Attenuation ◽

Central United States ◽

Using Data ◽

Spatial Attenuation

abstract Attenuation of ground motion in the central United States has to be determined principally using the Modified Mercalli (MM) intensity observations because of the absence of instrumental strong ground-motion data. Nuttli's previous studies of Mississippi Valley earthquakes indicate that higher-mode surface waves produce the largest ground motion except possibly in the near-field region. Particle velocity rather than acceleration correlates directly with intensity and the coefficient of anelastic attenuation has an average value of 0.10 per degree. Using data from isoseismals of the November 9, 1968, southern Illinois and the December 16, 1811, New Madrid, Missouri earthquakes and assuming a linear relationship between log(A/T) and MM intensity, attenuation is expressed by the equation, valid for I(R) ≧IV (MM), I ( R ) = I 0 + 3.7 − 0.0011 R − 2.7 log ⁡ R ; for R ≧ 20 k m where R is the epicentral distance in kilometers. This relationship shows fairly good agreement with isoseismals of many large earthquakes in the central United States and may therefore be useful in providing realistic estimates of spatial attenuation and hence of design earthquakes for a given site. It can also be sometimes useful in estimating the epicentral intensity of an earthquake whose maximum intensity is not reliably known.

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Racial and Ethnic Disparities in Years of Potential Life Lost Attributable to COVID-19 in the United States: An Analysis of 45 States and the District of Columbia

10.1101/2021.01.28.21249411 ◽

2021 ◽

Author(s):

Jay J. Xu ◽

Jarvis T. Chen ◽

Thomas R. Belin ◽

Ronald S. Brookmeyer ◽

Marc A. Suchard ◽

...

Keyword(s):

United States ◽

District Of Columbia ◽

Ethnic Disparities ◽

The United States ◽

Attributable Mortality ◽

Estimation Uncertainty ◽

Race Ethnicity ◽

Using Data ◽

Rate Ratios ◽

Racial Ethnic

AbstractThe coronavirus disease 2019 (COVID-19) epidemic in the United States has disproportionately impacted communities of color across the country. Focusing on COVID-19-attributable mortality, we expand upon a national comparative analysis of years of potential life lost (YPLL) attributable to COVID-19 by race/ethnicity (Bassett et al., 2020), estimating percentages of total YPLL for non-Hispanic Whites, non-Hispanic Blacks, Hispanics, non-Hispanic Asians, and non-Hispanic American Indian or Alaska Natives, contrasting them with their respective percent population shares, as well as age-adjusted YPLL rate ratios – anchoring comparisons to non-Hispanic Whites – in each of 45 states and the District of Columbia using data from the National Center for Health Statistics as of December 30, 2020. Using a novel Monte Carlo simulation procedure to quantify estimation uncertainty, our results reveal substantial racial/ethnic disparities in COVID-19-attributable YPLL across states, with a prevailing pattern of non-Hispanic Blacks and Hispanics experiencing disproportionately high and non-Hispanic Whites experiencing disproportionately low COVID-19-attributable YPLL. Furthermore, observed disparities are generally more pronounced when measuring mortality in terms of YPLL compared to death counts, reflecting the greater intensity of the disparities at younger ages. We also find substantial state-to-state variability in the magnitudes of the estimated racial/ethnic disparities, suggesting that they are driven in large part by social determinants of health whose degree of association with race/ethnicity varies by state.

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A numerical study of peak ground motion scaling

Bulletin of the Seismological Society of America ◽

10.1785/bssa0710061963 ◽

1981 ◽

Vol 71 (6) ◽

pp. 1963-1979

Author(s):

Robert B. Herrmann ◽

Michael J. Goertz

Keyword(s):

United States ◽

Data Base ◽

Ground Motion ◽

Numerical Study ◽

Model Parameters ◽

Data Set ◽

States Data ◽

Central United States ◽

Motion Scaling ◽

Ground Motion Scaling

Abstract Strong ground motion scaling relations for the Central United States cannot be obtained by applying regression analysis to the existing, sparse data base. Adaptation of the corresponding Western United States data base must be done carefully because the important problems of differences in regional anelastic attenuation, magnitude scales, and earthquake source physics still have to be resolved. Until this is done, empirical relations have to be adapted, but some test of their validity must be made. Since the Central United States data set is not a valid test, synthetic seismograms can be used to test some of the assumptions and results. The Central United States ground motion scaling problem differs from usual experience in that the nature of ground motion scaling at distances greater than 100 km from the source is of utmost importance. Numerical techniques are used to generate SH time histories in a four layer Central United States earth model. A study of model parameters indicates that simple deductions based on the scaling of pulses are applicable to the high-frequency surface wave trains at large distances and that spatial attenuation for these waves should be of the form R − 5 / 6 exp (−γR) . An attempt to apply the results of the numerical study to the existing Central United States data base is not too impressive because of the limited frequency range of the synthetics and lack of detailed knowledge about earth structure in the Mississippi embayment, from which the actual data were obtained.

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Political Centralization, Federalism, and Urban Development: Evidence from US and Canadian Capital Cities

Social Science History ◽

10.1017/ssh.2015.83 ◽

2016 ◽

Vol 40 (1) ◽

pp. 121-146 ◽

Cited By ~ 2

Author(s):

Sukkoo Kim ◽

Marc T. Law

Keyword(s):

United States ◽

Urban Development ◽

The United States ◽

Capital City ◽

Empirical Literature ◽

Capital Cities ◽

Institutional Differences ◽

Political Centralization ◽

Using Data ◽

The Impact

A growing empirical literature links political centralization with urban development. In this paper we present evidence showing how different patterns of political centralization in the United States and Canada affected urban agglomeration during the twentieth century, with a specific focus on the impact on the population of capital cities. Using data on Canadian and US cities and metropolitan areas, we find that the national capital effect on population grew over time in both countries but more so in the United States whereas the subnational (i.e., provincial or state) capital effect rose much more significantly in Canada than in the United States, controlling for other factors like geography and climate. We argue that these patterns in the national and subnational capital city effects reflect different trends in federalism in the two countries. In the United States, the Jeffersonian-Jacksonian tradition of states’ rights and localism was transformed into a more nationally centralized form of federalism during the Progressive Era, but states and localities continued to retain significant autonomy. In Canada, federalism came to favor provincial rights but not localism. We believe that that these diverging trends were driven by institutional differences that gave the various levels of governments in Canada and the United States different access to revenue sources.

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Bioclimatic analyses for the distributions ofOnthophagus nuchicornis,Onthophagus taurus, andDigitonthophagus gazella(Coleoptera: Scarabaeidae) in North America

The Canadian Entomologist ◽

10.4039/tce.2017.20 ◽

2017 ◽

Vol 149 (4) ◽

pp. 504-524 ◽

Cited By ~ 7

Author(s):

K.D. Floate ◽

D.W. Watson ◽

R.M. Weiss ◽

O. Olfert

Keyword(s):

United States ◽

North America ◽

United States Of America ◽

Dung Beetles ◽

Cattle Dung ◽

Human Intervention ◽

Onthophagus Taurus ◽

The World ◽

Central United States ◽

Using Data

AbstractOnthophagus nuchicornis(Linnaeus),Onthophagus taurus(Schreber), andDigitonthophagus gazella(Fabricius) (Coleoptera: Scarabaeidae: Scarabaeinae: Onthophagini) are species of dung beetles that have been used in relocation programmes to accelerate the degradation of cattle dung on pastures. Exotic in North America, all three species have expanded their distributions since their introduction onto the continent. Here we report development of CLIMEX®bioclimatic models using data collected before 2011 that predict the eventual North American distributions of these species. Data collected after 2010 is used to validate these models. Model outputs identify large regions of the central United States of America suitable for establishment ofO. nuchicornisandO. tauruswhere these species have not been reported. These results indicate that the latter two species may already be present in these regions and undetected, that they have yet to expand into these regions, and (or) that factors restricting migration or dispersal prevent these species from occupying these areas. Model outputs forD. gazellasuggest that the species has largely reached its predicted maximum distribution. These models can be used to aid the success of future relocation programmes elsewhere in the world and (or) to predict regions where these species are likely to spread without human intervention.

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Migration and the Internet

MIGRATION LETTERS ◽

10.33182/ml.v14i3.347 ◽

2017 ◽

Vol 14 (3) ◽

pp. 331-342 ◽

Cited By ~ 6

Author(s):

Thomas John Cooke ◽

Ian Shuttleworth

Keyword(s):

United States ◽

Information And Communication Technologies ◽

Unobserved Heterogeneity ◽

Panel Study ◽

The United States ◽

Negative Effect ◽

Information And Communication ◽

Using Data ◽

And Migration ◽

Dynamics Models

It is widely presumed that information and communication technologies, or ICTs, enable migration in several ways; primarily by reducing the costs of migration. However, a reconsideration of the relationship between ICTs and migration suggests that ICTs may just as well hinder migration; primarily by reducing the costs of not moving. Using data from the US Panel Study of Income Dynamics, models that control for sources of observed and unobserved heterogeneity indicate a strong negative effect of ICT use on inter-state migration within the United States. These results help to explain the long-term decline in internal migration within the United States.

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