scholarly journals Biogeographic multi-species occupancy models for large-scale survey data

2021 ◽  
Author(s):  
Jacob B Socolar ◽  
Simon C. Mills ◽  
Torbjorn Haugaasen ◽  
James J Gilroy ◽  
David P. Edwards
Keyword(s):  
Survey Data ◽  
Hierarchical Models ◽  
Large Scale ◽  
Spatial Scales ◽  
Computational Cost ◽  
The United States ◽  
Range Data ◽  
Occupancy Models ◽  
Multiple Species ◽  
Species Occupancy

Ecologists often seek to infer patterns of species occurrence or community structure from survey data. Hierarchical models, including multi-species occupancy models (MSOMs), can improve inference by pooling information across multiple species via random effects. Originally developed for local-scale survey data, MSOMs are increasingly applied to larger spatial scales that transcend major abiotic gradients and dispersal barriers. At biogeographic scales, the benefits of partial pooling in MSOMs trade off against the difficulty of incorporating sufficiently complex spatial effects to account for biogeographic variation in occupancy across multiple species simultaneously. We show how this challenge can be overcome by incorporating pre-existing range information into MSOMs, yielding a 'biogeographic multi-species occupancy model' (bMSOM). We illustrate the bMSOM using two published datasets: Parulid warblers in the United States Breeding Bird Survey, and entire avian communities in forests and pastures of Colombia's West Andes. Compared to traditional MSOMs, the bMSOM provides dramatically better predictive performance at lower computational cost. The bMSOM avoids severe spatial biases in predictions of the traditional MSOM and provides principled species-specific inference even for never-observed species. Incorporating pre-existing range data enables principled partial pooling of information across species in large-scale MSOMs. Our biogeographic framework for multi-species modeling should be broadly applicable in hierarchical models that predict species occurrences, whether or not false-absences are modeled in an occupancy framework.

scholarly journals Flood Risk Assessment and Quantification at the Community and Property Level in the State of Iowa

2021 ◽  
Author(s):  
Enes Yildirim ◽  
Ibrahim Demir
Keyword(s):  
Risk Assessment ◽  
High Resolution ◽  
Flood Risk ◽  
Large Scale ◽  
Spatial Scales ◽  
The United States ◽  
Flood Risk Assessment ◽  
Study Region ◽  
Study Results ◽  
Flood Maps

Flood risk assessment contributes to identifying at-risk communities and supports mitigation decisions to maximize benefits from the investments. Large-scale risk assessments generate invaluable inputs for prioritizing regions for the distribution of limited resources. High-resolution flood maps and accurate parcel information are critical for flood risk analysis to generate reliable outcomes for planning, preparedness, and decision-making applications. Large-scale damage assessment studies in the United States often utilize the National Structure Inventory (NSI) or HAZUS default dataset, which results in inaccurate risk estimates due to the low geospatial accuracy of these datasets. On the other hand, some studies utilize higher resolution datasets, however they are limited to focus on small scales, for example, a city or a Hydrological United Code (HUC)-12 watershed. In this study, we collected extensive detailed flood maps and parcel datasets for many communities in Iowa to carry out a large-scale flood risk assessment. High-resolution flood maps and the most recent parcel information are collected to ensure the accuracy of risk products. The results indicate that the Eastern Iowa communities are prone to a higher risk of direct flood losses. Our model estimates nearly $10 million in average annualized losses, particularly in large communities in the study region. The study highlights that existing risk products based on FEMA's flood risk output underestimate the flood loss, specifically in highly populated urban communities such as Bettendorf, Cedar Falls, Davenport, Dubuque, and Waterloo. Additionally, we propose a flood risk score methodology for two spatial scales (e.g., HUC-12 watershed, property) to prioritize regions and properties for mitigation purposes. Lastly, the watershed-scale study results are shared through a web-based platform to inform the decision-makers and the public.

scholarly journals Orogenic Propagating Precipitation Systems over the United States in a Global Climate Model with Embedded Explicit Convection

2011 ◽  
Vol 68 (8) ◽  
pp. 1821-1840 ◽  
Author(s):  
Michael S. Pritchard ◽  
Mitchell W. Moncrieff ◽  
Richard C. J. Somerville
Keyword(s):  
Large Scale ◽  
Global Climate ◽  
Spatial Scales ◽  
Global Climate Model ◽  
The United States ◽  
Global Climate Models ◽  
Convective Heating ◽  
Convective Systems ◽  
Synoptic Conditions ◽  
Cloud Resolving Model

Abstract In the lee of major mountain chains worldwide, diurnal physics of organized propagating convection project onto seasonal and climate time scales of the hydrologic cycle, but this phenomenon is not represented in conventional global climate models (GCMs). Analysis of an experimental version of the superparameterized (SP) Community Atmosphere Model (CAM) demonstrates that propagating orogenic nocturnal convection in the central U.S. warm season is, however, representable in GCMs that use the embedded explicit convection model approach [i.e., multiscale modeling frameworks (MMFs)]. SP-CAM admits propagating organized convective systems in the lee of the Rockies during synoptic conditions similar to those that generate mesoscale convective systems in nature. The simulated convective systems exhibit spatial scales, phase speeds, and propagation speeds comparable to radar observations, and the genesis mechanism in the model agrees qualitatively with established conceptual models. Convective heating and condensate structures are examined on both resolved scales in SP-CAM, and coherently propagating cloud “metastructures” are shown to transcend individual cloud-resolving model arrays. In reconciling how this new mode of diurnal convective variability is admitted in SP-CAM despite the severe idealizations in the cloud-resolving model configuration, an updated discussion is presented of what physics may transcend the re-engineered scale interface in MMFs. The authors suggest that the improved diurnal propagation physics in SP-CAM are mediated by large-scale first-baroclinic gravity wave interactions with a prognostic organization life cycle, emphasizing the physical importance of preserving “memory” at the inner resolved scale.

scholarly journals REEF3D:NSEWAVE, A THREE-DIMENSIONAL NON-HYDROSTATIC WAVE MODEL ON A FIXED GRID

2018 ◽  
pp. 8
Author(s):  
Hans Bihs ◽  
Kristina Heveling ◽  
Arun Kamath
Keyword(s):  
Large Scale ◽  
Stokes Equations ◽  
Spatial Scales ◽  
Phase Interface ◽  
Computational Cost ◽  
Three Dimensional ◽  
Free Water ◽  
Wave Model ◽  
Breaking Waves ◽  
Interface Capturing

For coastal engineering problems, wave modeling is required for various spatial scales. In recent years, the development of high-resolution Computational Fluid Dynamics (CFD) based numerical wave tanks (NWT) has gained a lot of attention. Here, the Navier-Stokes equations are solved together with a two-phase interface capturing algorithm for the calculation of the free surface location. The interface capturing treatment of the free water surface is performed on fixed grids, allowing for the simulation of complex wave phenomena such as breaking waves. The CFD-based NWT are preferably used for nearfield problems, such as wave-structure interaction. For larger spatial scales, the computational cost becomes rather expensive. In the current paper, the three-dimensional open-source hydrodynamics model REEF3D is extended from a CFD-based NWT to a non-hydrostatic wave model, suitable for economic large scale computation of waves.

Dissimilar biodiversity data sets yield congruent patterns and inference in lichens

Botany ◽  
2020 ◽  
Author(s):  
James C. Lendemer ◽  
Jessica Coyle
Keyword(s):  
Environmental Variables ◽  
Large Scale ◽  
Spatial Scales ◽  
Geographic Region ◽  
Individual Species ◽  
Data Sets ◽  
Biodiversity Data ◽  
Regional Species Pool ◽  
Secondary Analyses ◽  
Multiple Species

Large-scale efforts to aggregate and promote the re-use of biodiversity data are leading to novel insights into biogeography and macroecology. However, secondary analyses must account for the tradeoffs and limitations of the original studies. Studies of speciose and taxonomically complex groups often utilize morphospecies or functional subsets as proxies, potentially complicating data re-use. We evaluated whether lichen biodiversity patterns are robust to differences in sampling methodology, utilizing parallel analyses to compare species richness, regional species pool variation, species probabilities of occurrence, and correlation of those three with environmental variables in data sets that cover the same geographic region. Analyses revealed that, although individual species distributions sometimes differed in idiosyncratic ways, inference based on the aggregated response of multiple species was generally robust across the two datasets, despite differences in observer expertise and functional and taxonomic scope. This suggests that biodiversity data assembled from disparate sources could be used to evaluate biogeographical and macroecological hypotheses in understudied groups such as lichens, particularly at larger spatial scales.

Suborbital Measurements of Spectral Aerosol Optical Depth and Its Variability at Subsatellite Grid Scales in Support of CLAMS 2001

2005 ◽  
Vol 62 (4) ◽  
pp. 993-1007 ◽  
Author(s):  
J. Redemann ◽  
B. Schmid ◽  
J. A. Eilers ◽  
R. Kahn ◽  
R. C. Levy ◽  
...  
Keyword(s):  
Spatial Variability ◽  
Aerosol Optical Depth ◽  
Optical Depth ◽  
Large Scale ◽  
Spatial Scales ◽  
The United States ◽  
Horizontal Distance ◽  
Airborne Measurements ◽  
Low Level ◽  
Modis Aod

Abstract As part of the Chesapeake Lighthouse and Aircraft Measurements for Satellites (CLAMS) experiment, 10 July–2 August 2001, off the central East Coast of the United States, the 14-channel NASA Ames Airborne Tracking Sunphotometer (AATS-14) was operated aboard the University of Washington’s Convair 580 (CV-580) research aircraft during 10 flights (∼45 flight hours). One of the main research goals in CLAMS was the validation of satellite-based retrievals of aerosol properties. The goal of this study in particular was to perform true over-ocean validations (rather than over-ocean validation with ground-based, coastal sites) at finer spatial scales and extending to longer wavelengths than those considered in previous studies. Comparisons of aerosol optical depth (AOD) between the Aerosol Robotic Network (AERONET) Cimel instrument at the Chesapeake Lighthouse and airborne measurements by AATS-14 in its vicinity showed good agreement with the largest r-square correlation coefficients at wavelengths of 0.38 and 0.5 μm (>0.99). Coordinated low-level flight tracks of the CV-580 during Terra overpass times permitted validation of over-ocean Moderate Resolution Imaging Spectroradiometer (MODIS) level 2 (MOD04_L2) multiwavelength AOD data (10 km × 10 km, nadir) in 16 cases on three separate days. While the correlation between AATS-14- and MODIS-derived AOD was weak with an r square of 0.55, almost 75% of all MODIS AOD measurements fell within the prelaunch estimated uncertainty range Δτ = ±0.03 ± 0.05τ. This weak correlation may be due to the small AODs (generally less than 0.1 at 0.5 μm) encountered in these comparison cases. An analogous coordination exercise resulted in seven coincident over-ocean matchups between AATS-14 and Multiangle Imaging Spectroradiometer (MISR) measurements. The comparison between AATS-14 and the MISR standard algorithm regional mean AODs showed a stronger correlation with an r square of 0.94. However, MISR AODs were systematically larger than the corresponding AATS values, with an rms difference of ∼0.06. AATS data collected during nine extended low-level CV-580 flight tracks were used to assess the spatial variability in AOD at horizontal scales up to 100 km. At UV and midvisible wavelengths, the largest absolute gradients in AOD were 0.1–0.2 per 50-km horizontal distance. In the near-IR, analogous gradients rarely reached 0.05. On any given day, the relative gradients in AOD were remarkably similar for all wavelengths, with maximum values of 70% (50 km)−1 and more typical values of 25% (50 km)−1. The implications of these unique measurements of AOD spatial variability for common validation practices of satellite data products and for comparisons to large-scale aerosol models are discussed.

Surface flux equilibrium estimates of evapotranspiration at large spatial scales

2021 ◽  
Author(s):  
Shiliu Chen ◽  
Kaighin A. McColl ◽  
Alexis Berg ◽  
Yuefei Huang
Keyword(s):  
Water Balance ◽  
Land Surface ◽  
Large Scale ◽  
Spatial Scales ◽  
Bowen Ratio ◽  
Surface Flux ◽  
The United States ◽  
Surface Energy Budget ◽  
Recent Theory ◽  
Atmospheric Measurements

AbstractA recent theory proposes that inland continental regions are in a state of ‘surface flux equilibrium’ (SFE), in which tight coupling between the land and atmosphere allow estimation of the Bowen ratio at daily to monthly time scales solely from atmospheric measurements, without calibration, even when the land surface strongly constrains the surface energy budget. However, since the theory has only been evaluated at quasi-point spatial scales using eddy covariance measurements with limited global coverage, it is unclear if it is applicable to the larger spatial scales relevant to studies of global climate. In this study, SFE estimates of the Bowen ratio are combined with satellite observations of surface net radiation to obtain large-scale estimates of latent heat flux (λE). When evaluated against multiyear mean annual λE obtained from catchment water balance estimates from 221 catchments across the United States, the resulting error statistics are comparable to those in the catchment water balance estimates themselves. The theory is then used to diagnostically estimate λE using historical simulations from 26 CMIP6 models. The resulting SFE estimates are typically at least as accurate as the CMIP6 model’s simulated λE, when compared with catchment water balance estimates. Globally, there is broad spatial and temporal agreement between CMIP6 model SFE estimates and the CMIP6 model’s simulated λE, although SFE likely overestimates λE in some arid regions. We conclude that SFE applies reasonably at large spatial scales relevant to climate studies, and is broadly reproduced in climate models.

scholarly journals Seismic surveys reduce cetacean sightings across a large marine ecosystem

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
A. S. Kavanagh ◽  
M. Nykänen ◽  
W. Hunt ◽  
N. Richardson ◽  
M. J. Jessopp
Keyword(s):  
Large Scale ◽  
Spatial Scales ◽  
Marine Ecosystem ◽  
Noise Pollution ◽  
Marine Species ◽  
Seismic Survey ◽  
Specific Response ◽  
Seismic Surveys ◽  
Large Marine Ecosystem ◽  
Multiple Species

AbstractNoise pollution is increasing globally, and as oceans are excellent conductors of sound, this is a major concern for marine species reliant on sound for key life functions. Loud, impulsive sounds from seismic surveys have been associated with impacts on many marine taxa including mammals, crustaceans, cephalopods, and fish. However, impacts across large spatial scales or multiple species are rarely considered. We modelled over 8,000 hours of cetacean survey data across a large marine ecosystem covering > 880,000 km2 to investigate the effect of seismic surveys on baleen and toothed whales. We found a significant effect of seismic activity across multiple species and habitats, with an 88% (82–92%) decrease in sightings of baleen whales, and a 53% (41–63%) decrease in sightings of toothed whales during active seismic surveys when compared to control surveys. Significantly fewer sightings of toothed whales also occurred during active versus inactive airgun periods of seismic surveys, although some species-specific response to noise was observed. This study provides strong evidence of multi-species impacts from seismic survey noise on cetaceans. Given the global proliferation of seismic surveys and large propagation distances of airgun noise, our results highlight the large-scale impacts that marine species are currently facing.

Quality Control of Data in a Large-Scale Cancer Register Program

1966 ◽  
Vol 05 (02) ◽  
pp. 67-74 ◽  
Author(s):  
W. I. Lourie ◽  
W. Haenszeland
Keyword(s):  
United States ◽  
Quality Control ◽  
Cancer Patients ◽  
Large Scale ◽  
The United States ◽  
Newly Diagnosed ◽  
Related Data ◽  
Cancer Register ◽  
Independent Review ◽  
End Results

Quality control of data collected in the United States by the Cancer End Results Program utilizing punchcards prepared by participating registries in accordance with a Uniform Punchcard Code is discussed. Existing arrangements decentralize responsibility for editing and related data processing to the local registries with centralization of tabulating and statistical services in the End Results Section, National Cancer Institute. The most recent deck of punchcards represented over 600,000 cancer patients; approximately 50,000 newly diagnosed cases are added annually.Mechanical editing and inspection of punchcards and field audits are the principal tools for quality control. Mechanical editing of the punchcards includes testing for blank entries and detection of in-admissable or inconsistent codes. Highly improbable codes are subjected to special scrutiny. Field audits include the drawing of a 1-10 percent random sample of punchcards submitted by a registry; the charts are .then reabstracted and recoded by a NCI staff member and differences between the punchcard and the results of independent review are noted.

Utopias of One

2019 ◽  
Author(s):  
Joshua Kotin
Keyword(s):  
United States ◽  
Soviet Union ◽  
World War I ◽  
Large Scale ◽  
Jim Crow ◽  
Personal Autonomy ◽  
The United States ◽  
Soviet Period ◽  
Original Research ◽  
The Soviet Union

This book is a new account of utopian writing. It examines how eight writers—Henry David Thoreau, W. E. B. Du Bois, Osip and Nadezhda Mandel'shtam, Anna Akhmatova, Wallace Stevens, Ezra Pound, and J. H. Prynne—construct utopias of one within and against modernity's two large-scale attempts to harmonize individual and collective interests: liberalism and communism. The book begins in the United States between the buildup to the Civil War and the end of Jim Crow; continues in the Soviet Union between Stalinism and the late Soviet period; and concludes in England and the United States between World War I and the end of the Cold War. In this way it captures how writers from disparate geopolitical contexts resist state and normative power to construct perfect worlds—for themselves alone. The book contributes to debates about literature and politics, presenting innovative arguments about aesthetic difficulty, personal autonomy, and complicity and dissent. It models a new approach to transnational and comparative scholarship, combining original research in English and Russian to illuminate more than a century and a half of literary and political history.

The Obesity Epidemic in Chinese American Youth?: A Literature Review and Pilot Study

2008 ◽  
Vol 6 (1) ◽  
pp. 31-42 ◽  
Author(s):  
Robyn Matloff ◽  
Angela Lee ◽  
Roland Tang ◽  
Doug Brugge
Keyword(s):  
Asian Americans ◽  
Ethnic Diversity ◽  
Large Scale ◽  
Community Health Center ◽  
Chinese American ◽  
The United States ◽  
Overweight And Obesity ◽  
Waiting Room ◽  
Obesity Epidemic ◽  
American Children

Despite nearly 12 million Asian Americans living in the United States and continued immigration, this increasingly substantial subpopulation has consistently been left out of national obesity studies. When included in national studies, Chinese-American children have been grouped together with other Asian Americans, Pacific Islanders or simply as “other,” yielding significantly lower rates of overweight and obesity compared to non-Asians. There is a failure to recognize the ethnic diversity of Asian Americans as well as the effect of acculturation. Results from smaller studies of Chinese American youth suggest that they are adopting lifestyles less Chinese and more Americans and that their share of disease burden is growing. We screened 142 children from the waiting room of a community health center that serves primarily recent Chinese immigrants for height, weight and demographic profile. Body Mass Index was calculated and evaluated using CDC growth charts. Overall, 30.1 percent of children were above the 85th we found being male and being born in the U .S. to be statistically significant for BMI > 85th percentile (p=0.039, p=0.001, respectively). Our results suggest that being overweight in this Chinese American immigrant population is associated with being born in the U.S. A change in public policy and framework for research are required to accurately assess the extent of overweight and obesity in Chinese American children. In particular, large scale data should be stratified by age, sex, birthplace and measure of acculturation to identify those at risk and construct tailored interventions.

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