scholarly journals A Statistical Model for Estimating Midday NDVI from the Geostationary Operational Environmental Satellite (GOES) 16 and 17

2019 ◽  
Vol 11 (21) ◽  
pp. 2507 ◽  
Author(s):  
Kathryn I. Wheeler ◽  
Michael C. Dietze

The newest version of the Geostationary Operational Environmental Satellite series (GOES-16 and GOES-17) includes a near infrared band that allows for the calculation of normalized difference vegetation index (NDVI) at a 1 km at nadir spatial resolution every five minutes throughout the continental United States and every ten minutes for much of the western hemisphere. The usefulness of individual NDVI observations is limited due to the noise that remains even after cloud masks and data quality flags are applied, as much of this noise is negatively biased due to scattering within the atmosphere. Fortunately, high temporal resolution NDVI allows for the identification of consistent diurnal patterns. Here, we present a novel statistical model that utilizes this pattern, by fitting double exponential curves to the diurnal NDVI data, to provide a daily estimate of NDVI over forests that is less sensitive to noise by accounting for both random observation errors and atmospheric scattering biases. We fit this statistical model to 350 days of observations for fifteen deciduous broadleaf sites in the United States and compared the method to several simpler potential methods. Of the days 60% had more than ten observations and were able to be modeled via our methodology. Of the modeled days 72% produced daily NDVI estimates with <0.1 wide 95% confidence intervals. Of the modeled days 13% were able to provide a confident NDVI value even if there were less than five observations between 10:00–14:00. This methodology provides estimates for daily midday NDVI values with robust uncertainty estimates, even in the face of biased errors and missing midday observations.

2021 ◽  
pp. 003335492098521
Author(s):  
Alexia V. Harrist ◽  
Clinton J. McDaniel ◽  
Jonathan M. Wortham ◽  
Sandy P. Althomsons

Introduction Pediatric tuberculosis (TB) cases are sentinel events for Mycobacterium tuberculosis transmission in communities because children, by definition, must have been infected relatively recently. However, these events are not consistently identified by genotype-dependent surveillance alerting methods because many pediatric TB cases are not culture-positive, a prerequisite for genotyping. Methods We developed 3 potential indicators of ongoing TB transmission based on identifying counties in the United States with relatively high pediatric (aged <15 years) TB incidence: (1) a case proportion indicator: an above-average proportion of pediatric TB cases among all TB cases; (2) a case rate indicator: an above-average pediatric TB case rate; and (3) a statistical model indicator: a statistical model based on a significant increase in pediatric TB cases from the previous 8-quarter moving average. Results Of the 249 US counties reporting ≥2 pediatric TB cases during 2009-2017, 240 and 249 counties were identified by the case proportion and case rate indicators, respectively. The statistical model indicator identified 40 counties with a significant increase in the number of pediatric TB cases. We compared results from the 3 indicators with an independently generated list of 91 likely transmission events involving ≥2 pediatric cases (ie, known TB outbreaks or case clusters with reported epidemiologic links). All counties with likely transmission events involving multiple pediatric cases were identified by ≥1 indicator; 23 were identified by all 3 indicators. Practice Implications This retrospective analysis demonstrates the feasibility of using routine TB surveillance data to identify counties where ongoing TB transmission might be occurring, even in the absence of available genotyping data.


1965 ◽  
Vol 7 (3) ◽  
pp. 345-356 ◽  
Author(s):  
Wesley Phillips Newton

In Latin America, international rivalry over aviation followed World War I. In its early form, it consisted of a commercial scramble among several Western European nations and the United States to sell airplanes and aviation products and to establish airlines in Latin America. Somewhat later, expanding European aviation activities posed an implicit threat to the Panama Canal.Before World War I, certain aerophiles had sought to advance the airplane as the panacea for the transportation problem in Latin America. The aviation pioneer Alberto Santos-Dumont of Brazil and the Aero Club of America, an influential private United States association, were in the van. In 1916, efforts by these enthusiasts led to the formation of the Pan American Aviation Federation, which they envisioned as the means of promoting and publicizing aviation throughout the Western Hemisphere.


1965 ◽  
Vol 29 (3) ◽  
pp. 146
Author(s):  
Henry Zamensky ◽  
Stetson Conn ◽  
Rose C. Engelman ◽  
Byron Fairchild

2021 ◽  
Author(s):  
Danielle M Tufts ◽  
Maria A Diuk-Wasser

Abstract Invasive arthropod vectors and the range expansions of native vectors can lead to public and veterinary health concerns, as these vectors may introduce novel pathogens or spread endemic pathogens to new locations. Recent tick invasions and range expansion in the United States has been attributed to climate and land use change, an increase in global travel, and importations of exotic animals. A 10 year surveillance study was conducted on Block Island, Rhode Island from 2010–2020 including sampling ticks from small mammal and avian hosts. We report the discovery and establishment of the red sheep tick for the first time in the western hemisphere and in the United States. This invasive species was first collected in 2010 on Block Island, was collected continuously throughout the study, and was collected from an avian host. We document the first report of the invasive Asian longhorned tick in the state of Rhode Island, first observed at our sites in 2018. Finally, we present data on the range expansion and establishment of two native tick species, the lone star tick and the rabbit tick on Block Island. This study emphasized the importance of long-term surveillance to detect changes in tick host communities, including invasive and expanding native vectors of potential significance to humans and wildlife.


Weed Science ◽  
2004 ◽  
Vol 52 (2) ◽  
pp. 185-200 ◽  
Author(s):  
Theodore M. Webster ◽  
John Cardina

Florida beggarweed is native to the Western Hemisphere but is naturalized around the world. During the last century, the mechanization of agriculture has transitioned Florida beggarweed from an important forage component to a weed of significance in the coastal plain of the southeast United States. This herbaceous annual is naturalized and found in fields and disturbed areas throughout the southern United States. The characteristics that made Florida beggarweed a good forage crop also make it a formidable weed. This review describes the importance of Florida beggarweed as a weed in the southern United States and the taxonomy of this species and details the distribution throughout the world and within the United States. The ecology of Florida beggarweed and its interactions with crop plants, insects, nematodes, and plant pathogens also are summarized. Finally, management of Florida beggarweed in agricultural systems using cultural practices and herbicides is reviewed.


2014 ◽  
Vol 1 (2) ◽  
pp. 7-9
Author(s):  
Sergio Escobar-Lasso ◽  
Margarita Gil-Fernández

The long-tailed weasel Mustela frenata Lichtenstein, 1831 has the greatest geographical range among mustelids in the western hemisphere (Harding & Dragoo 2012). The range of M. frenata extends from the north of the United States, near the Canadian border, to northern South America (Sheffield & Thomas 1997), from sea level to 3800 masl (Sheffield & Thomas 1997, Reid & Helgen 2008).


Author(s):  
Erica N. Spotswood ◽  
Matthew Benjamin ◽  
Lauren Stoneburner ◽  
Megan M. Wheeler ◽  
Erin E. Beller ◽  
...  

AbstractUrban nature—such as greenness and parks—can alleviate distress and provide space for safe recreation during the COVID-19 pandemic. However, nature is often less available in low-income populations and communities of colour—the same communities hardest hit by COVID-19. In analyses of two datasets, we quantified inequity in greenness and park proximity across all urbanized areas in the United States and linked greenness and park access to COVID-19 case rates for ZIP codes in 17 states. Areas with majority persons of colour had both higher case rates and less greenness. Furthermore, when controlling for sociodemographic variables, an increase of 0.1 in the Normalized Difference Vegetation Index was associated with a 4.1% decrease in COVID-19 incidence rates (95% confidence interval: 0.9–6.8%). Across the United States, block groups with lower income and majority persons of colour are less green and have fewer parks. Our results demonstrate that the communities most impacted by COVID-19 also have the least nature nearby. Given that urban nature is associated with both human health and biodiversity, these results have far-reaching implications both during and beyond the pandemic.


Sign in / Sign up

Export Citation Format

Share Document