scholarly journals Presence of Longitudinal Roll Structures during Synoptic Forced Conditions in Complex Terrain

Atmosphere ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 737
Author(s):  
Cory M. Payne ◽  
Jeffrey E. Passner ◽  
Robert E. Dumais ◽  
Abdessattar Abdelkefi ◽  
Christopher M. Hocut

To investigate synoptic interactions with the San Andres Mountains in southern New Mexico, the Weather Research and Forecasting (WRF) model was used to simulate several days in the period 2018–2020. The study domain was centered on the U.S. Department of Agriculture (USDA) Agricultural Research Service’s Jornada Experimental Range (JER) and the emphasis was on synoptic conditions that favor strong to moderate winds aloft from the southwest, boundary layer shear, a lack of moisture (cloud coverage), and modest warming of the surface. The WRF simulations on these synoptic days revealed two distinct regimes: lee waves aloft and SW-to-NE oriented Longitudinal Roll Structures (LRS) that have typical length scales of the width of the mountain basin in the horizontal and the height of the boundary layer (BL) in the vertical. Analysis of the transitional periods indicate that the shift from the lee wave to LRS regime occurs when the surface heating and upwind flow characteristics reach a critical threshold. The existence of LRS is confirmed by satellite observations and the longitudinal streak patterns in the soil of the JER that indicate this is a climatologically present BL phenomenon.

2001 ◽  
Vol 126 (2) ◽  
pp. 205-209 ◽  
Author(s):  
Claudio Cantini ◽  
Amy F. Iezzoni ◽  
Warren F. Lamboy ◽  
Manuela Boritzki ◽  
Darush Struss

The U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS) tetraploid cherry (Prunus L. sp.) collection at Geneva, N.Y., contains ≈75 accessions of sour cherry (P. cerasus L.), ground cherry (P. fruticosa Pall.), and their hybrids. Accurate and unambiguous identification of these accessions is essential for germplasm preservation and use. Simple sequence repeats (SSRs) are currently the markers of choice for germplasm fingerprinting because they characteristically display high levels of polymorphism. Recently SSR primer pairs from sweet cherry (P. avium L.), sour cherry, and peach [(P. persica L. Batsch (Peach Group)] have been reported. Ten SSR primer pairs were tested on 59 tetraploid cherry accessions to determine if they could differentiate among the accessions. Scorable SSR fragments were produced with all primer-accession combinations. The cherry accessions exhibited high levels of polymorphism with 4 to 16 different putative alleles amplified per primer pair. Most of the putative alleles were rare with frequencies <0.05. Heterozygosity values ranged from 0.679 to 1.00, while gene diversity values ranged from 0.655 to 0.906. The primer pairs differentiated all but two of the 59 cherry accessions. Based upon the ability of the SSR data to differentiate the cherry accessions and the high level of gene diversity, we propose that all the tetraploid cherry accessions in the USDA/ARS collection be fingerprinted to provide a mechanism to verify the identity of the individual accessions. The fingerprinting data are available on the World Wide Web (http://www.ars-grin.gov/gen/cherry.html) so that other curators and scientists working with cherry can verify identities and novel types in their collections and contribute to a global database.


2012 ◽  
Vol 11 (2) ◽  
pp. 106-113 ◽  
Author(s):  
Dilip R. Panthee ◽  
Joanne A. Labate ◽  
Larry D. Robertson

Flavour is one of the most highly demanded consumer traits of tomato at present; poor flavour is one of the most commonly heard complaints associated with modern varieties of tomato. In order to combine flavour with other desirable fruit traits in improved cultivars, it is important to determine how much variability exists in the crucial compounds that contribute most to flavour. The objective of the present study was to determine the variability of flavour-contributing components including total soluble solids (TSS) and total titratable acids (TTA) among other subjective traits related to flavour in a core collection of tomato accessions. The core collection was comprised of 173 tomato accessions with a wide genetic background from the United States Department of Agriculture (USDA), Agricultural Research Services (ARS) Plant Genetic Resources Unit repository. The TTA varied from 0.20 to 0.64%, whereas the TSS ranged from 3.4 to 9.0%, indicating the availability of broad variation for these traits. Rinon (PI 118783), Turrialba, Purple Calabash and LA2102 were among the high TTA (>0.45%) containing accessions, whereas those with high TSS (>7.0%) were AVRDC#6, Sponzillo and LA2102. A positive correlation of overall flavour with TTA (r= 0.33; P< 0.05) and TSS (r= 0.37; P< 0.05) indicated that these two components play an important role in determining the overall flavour in tomato. Subjectively measured other traits including fruity odour and fruity flavour had positive correlations with overall flavour. Overall flavour is discussed in the context of other traits including fruit firmness. Information obtained from this study may be useful for tomato breeders aiming to improve tomato flavour.


2015 ◽  
Vol 72 (12) ◽  
pp. 4865-4884 ◽  
Author(s):  
Vanda Grubišić ◽  
Stefano Serafin ◽  
Lukas Strauss ◽  
Samuel J. Haimov ◽  
Jeffrey R. French ◽  
...  

Abstract Mountain waves and rotors in the lee of the Medicine Bow Mountains in southeastern Wyoming are investigated in a two-part paper. Part I by French et al. delivers a detailed observational account of two rotor events: one displays characteristics of a hydraulic jump and the other displays characteristics of a classic lee-wave rotor. In Part II, presented here, results of high-resolution numerical simulations are conveyed and physical processes involved in the formation and dynamical evolution of these two rotor events are examined. The simulation results reveal that the origin of the observed rotors lies in boundary layer separation, induced by wave perturbations whose amplitudes reach maxima at or near the mountain top. An undular hydraulic jump that gave rise to a rotor in one of these events was found to be triggered by midtropospheric wave breaking and an ensuing strong downslope windstorm. Lee waves spawning rotors developed under conditions favoring wave energy trapping at low levels in different phases of these two events. The upstream shift of the boundary layer separation zone, documented to occur over a relatively short period of time in both events, is shown to be the manifestation of a transition in flow regimes, from downslope windstorms to trapped lee waves, in response to a rapid change in the upstream environment, related to the passage of a short-wave synoptic disturbance aloft. The model results also suggest that the secondary obstacles surrounding the Medicine Bow Mountains play a role in the dynamics of wave and rotor events by promoting lee-wave resonance in the complex terrain of southeastern Wyoming.


Agriculture ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 223
Author(s):  
Xiaoyan Pan ◽  
Jialong Lv ◽  
Miles Dyck ◽  
Hailong He

Soil nutrient balance is related to the interaction mechanism between soil fertilizer, soil water, climate change, and plant capability. This paper provides a perspective from bibliometric analysis based on data from the Web of Science core collection with software tools, including Vosviewer, HistCite Pro, and Citespace, in order to reveal the evolution of research trends in soil nutrients. The results show that publication outputs have increased exponentially from 1992 to 2020. The synthetic parameter of the sum of normalized data (SND), calculated from the default indicators of the bibliometric software tools, was used to rank the overall contribution of journal/authors/institutions/countries. The results demonstrate that Agriculture Ecosystems & Environment, Soil Biology & Biochemistry and Science of the Total Environment are the leading journals in the soil nutrient field. The Chinese Academy of Sciences had the highest total citations and collaborated most closely with other organizations, followed by United States Department of Agriculture (USDA) Agricultural Research Service (ARS) and Agr& Agri Food Canada. In addition, USA, China, and UK are the top three research centers for this topic. Moreover, Ken E Giller, Qirong Shen, and Rattan Lal were the top three authors, while Andrew Sharpley ranked the first depending on citations per publication. In terms of co-occurrence of keyword analysis, the results indicate that nitrogen fertilizer, green manure, and soil population have gained close attention from scholars, while soil amendment of biochar have evolved as a hot topic in recent years. Perspectives on future studies are also given.


HortScience ◽  
2011 ◽  
Vol 46 (11) ◽  
pp. 1440-1443
Author(s):  
Kim E. Hummer

The U.S. Department of Agriculture (USDA), Agricultural Research Service, National Clonal Germplasm Repository in Corvallis was established as the U.S. National Plant Germplasm System's berry genebank in 1981. Since then, the USDA has sponsored numerous explorations throughout the United States and foreign countries to obtain berry plant genetic resources. Species of Fragaria L. (strawberries), Ribes L. (currants and gooseberries), Rubus L. (raspberries and blackberries), and Vaccinium L. (blueberries and cranberries) are native to both domestic and international localities. With limited gene pools for cultivated strawberries, raspberries, and blackberries, expeditions have provided a wealth of genetic resources to expand opportunities for breeders to develop new cultivars. Particularly given the diverse species inherent in the development of cultivated blueberries, these trips have discovered unusual new blueberry relatives and forms available for expanding the range of production, increasing plant yields, and improving fruit antioxidant content. Along the way, new fruit species and new uses for known species were observed. Gathering the bounty of the world's berries resulted in encounters with diverse fauna, from snakes, bears, and bison to butterflies, mosquitoes, ticks, and chiggers. Avenging Toxicodendron species have added their mark on intrepid explorers. Remote sites with nothing but clear night stars and the satellite markers on the global positioning system offer radiant beauty and an abiding hope for the conservation of plant genetic diversity for all people for all time.


2017 ◽  
Vol 56 (5) ◽  
pp. 1305-1324 ◽  
Author(s):  
Liye Li ◽  
Yi-Leng Chen

AbstractTwo trapped lee-wave events dominated by the transverse mode downstream of the island of Oahu in Hawaii—27 January 2010 and 24 January 2003—are simulated using the Weather Research Forecasting (WRF) Model with a horizontal grid size of 1 km in conjunction with the analyses of soundings, weather maps, and satellite images. The common factors for the occurrences of these transverse trapped mountain-wave events are 1) Froude number [Fr = U/(Nh)] > 1, where U is the upstream speed of the cross-barrier flow, N is stability, and h is the mountain height; 2) insufficient convective available potential energy for the air parcel to become positively buoyant after being lifted to the top of the stable trade wind inversion layer; and 3) increasing cross-barrier wind speed with respect to height through the stable inversion layer, satisfying Scorer’s criteria between the inversion layer and the layer aloft. Within the inversion layer, where the Scorer parameter has a maximum, the wave amplitudes are the greatest. The two trapped mountain waves in winter occurred under strong prefrontal stably stratified southwesterly flow. On the other islands in Hawaii, where the mountaintops are below the base of the inversion, transverse trapped lee waves can occur under similar large-scale settings if the mountain height is lower than U/N. The high-spatial-and-temporal-resolution WRF Model successfully simulates the onset, development, and dissipation of these two events. Sensitivity tests for the 27 January 2010 case are performed with reduced relative humidity (RH). With a lower RH and less-significant latent heating, trapped lee waves have smaller amplitudes and shorter wavelengths.


Between 2016 and 2018, the U.S. Department of Agriculture (USDA) Southern Plains Climate Hub led a project to assess the impacts of the recent historic 2016 and 2018wildfires on the Southern Plains. Titled the 2016-2018Southern Plains Wildfire Assessment, this project was coordinated with multiple agencies and organizations across the region including the Southern Climate Impacts Planning Program (SCIPP) a NOAA Regional Integrated Science and Assessment (RISA) team,University of Oklahoma’s Center for Spatial Analysis, and the USDA Agricultural Research Service (ARS) Grazinglands Research Laboratory, among others. Elements of this project included three local stakeholder events across the affected region as well as are search component investigating characteristics of vegetation recovery within these areas. The findings of both are coupled in this assessment report to encourage the risk reduction measures of future wildfire recovery and preparedness efforts across the Southern Plains.


2002 ◽  
Vol 65 (3) ◽  
pp. 567-570 ◽  
Author(s):  
JOHN B. LUCHANSKY ◽  
ANNA C. S. PORTO ◽  
F. MORGAN WALLACE ◽  
JEFFREY E. CALL

This study compared three methods for the recovery of Listeria monocytogenes from commercially prepared and vacuum-packaged frankfurters that were inoculated with a five-strain mixture of this pathogen at averages of 22 and 20,133 CFU per package over three trials. The presence and levels of the pathogen were determined by (i) the U.S. Department of Agriculture (USDA) Food Safety and Inspection Service (FSIS) product composite enrichment method, involving the selective enrichment of a 25-g composite of product and the subsequent plating of this product onto selective agar plates; (ii) the USDA Agricultural Research Service (ARS) product composite rinse method, involving the rinsing of a 25-g composite of product with 0.1% peptone water and the subsequent plating of a portion of the rinse fluid directly onto selective agar plates; and (iii) the USDA-ARS package rinse method, involving the use of 25 ml of 0.1% peptone water to rinse the entire contents of a package and the subsequent plating of a portion of the rinse fluid directly onto selective agar plates. For packages inoculated with 20,133 CFU, L. monocytogenes was recovered at a frequency (percentage of packages positive) of 100% by each of the three methods. The pathogen was recovered at efficiencies (percentages of recovery of L. monocytogenes) of 43 and 94% with the USDA-ARS product rinse method and the USDA-ARS package rinse method, respectively. For packages inoculated with 22 CFU, L. monocytogenes was recovered at frequencies of 17, 10, and 100% by the USDA-FSIS product composite enrichment method, the USDA-ARS product composite rinse method, and the USDA-ARS package rinse method, respectively. The pathogen was recovered at efficiencies of 20 and 95% with the USDA-ARS product composite rinse method and the USDA-ARS package rinse method, respectively. In a related study, the USDA-ARS package rinse method was the only method that detected the pathogen in 60 packages from each of five brands of frankfurters purchased from local grocery stores. These data establish that the USDA-ARS package rinse method is markedly more sensitive, as well as demonstrably more rapid and facile, than either the approved USDA-FSIS product composite enrichment method or the USDA-ARS product composite rinse method in determining the presence or absence of L. monocytogenes and establishing the levels of the pathogen that may be on the surface of ready-to-eat foods such as frankfurters.


2018 ◽  
Vol 57 (11) ◽  
pp. 2679-2696 ◽  
Author(s):  
Jennifer D. Hegarty ◽  
Jasper Lewis ◽  
Erica L. McGrath-Spangler ◽  
John Henderson ◽  
Amy Jo Scarino ◽  
...  

AbstractThe daytime planetary boundary layer (PBL) was examined for the Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality (DISCOVER-AQ) Baltimore (Maryland)–Washington, D.C., campaign of July 2011 using PBL height (PBLH) retrievals from aerosol backscatter measurements from ground-based micropulse lidar (MPL), the NASA Langley Research Center airborne High Spectral Resolution Lidar-1 (HSRL-1), and the Cloud–Aerosol Lidar with Orthogonal Polarization (CALIOP) on the Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite. High-resolution Weather Research and Forecasting (WRF) Model simulations with horizontal grid spacing of 1 km and different combinations of PBL schemes, urban parameterization, and sea surface temperature inputs were evaluated against PBLHs derived from lidars, ozonesondes, and radiosondes. MPL and WRF PBLHs depicted a growing PBL in the morning that reached a peak height by midafternoon. WRF PBLHs calculated from gridded output profiles generally showed more rapid growth and higher peak heights than did the MPLs, and all WRF–lidar differences were dependent on model configuration, PBLH calculation method, and synoptic conditions. At inland locations, WRF simulated an earlier descent of the PBL top in the afternoon relative to the MPL retrievals and radiosonde PBLHs. At Edgewood, Maryland, the influence of the Chesapeake Bay breeze on the PBLH was captured by both the ozonesonde and WRF data but generally not by the MPL PBLH retrievals because of generally weaker gradients in the aerosol backscatter profile and limited normalized relative backscatter data near the top height of the marine layer.


2020 ◽  
Vol 31 (3) ◽  
pp. 113-114
Author(s):  
Nelson Laville ◽  
Kenrick Witty ◽  
Ulises Garcia

The Beyond Compliance Global team held an interview by video link with Dr Eric Jang, United States Department of Agriculture, Agricultural Research Service (USDA/ARS), now retired. His lab was based in Hawaii, where he continues to reside. Eric was an early advocate and one of the originators of the concepts for Systems Approach.


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