scholarly journals Precipitation Deficit Flash Droughts over the United States

2016 ◽  
Vol 17 (4) ◽  
pp. 1169-1184 ◽  
Author(s):  
Kingtse C. Mo ◽  
Dennis P. Lettenmaier
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
Heat Wave ◽  
Great Plains ◽  
Land Surface ◽  
The United States ◽  
Southern Great Plains ◽  
Physical Mechanisms ◽  
The Pacific ◽  
Surface Models

Abstract Flash drought refers to relatively short periods of warm surface temperature and anomalously low and rapid decreasing soil moisture (SM). Based on the physical mechanisms associated with flash droughts, these events are classified into two categories: heat wave and precipitation P deficit flash droughts. In previous work, the authors have defined heat wave flash droughts as resulting from the confluence of severe warm air temperature Tair, which increases evapotranspiration (ET), and anomalously low and decreasing SM. Here, a second type of flash drought caused by precipitation deficits is explored. The authors term these events P-deficit flash droughts, which they associate with lack of P. Precipitation deficits cause ET to decrease and temperature to increase. The P-deficit flash droughts are analyzed based on observations of P, Tair, and SM and ET reconstructed using land surface models for the period 1916–2013. The authors find that P-deficit flash droughts are more common than heat wave flash droughts. They are about twice as likely to occur as heat wave flash droughts over the conterminous United States. They are most prevalent over the southern United States with maxima over the southern Great Plains and the Southwest, in contrast to heat wave flash droughts that are mostly likely to occur over the Midwest and the Pacific Northwest, where the vegetation cover is dense.

scholarly journals Race Characterization of Puccinia striiformis f. sp. tritici, the Cause of Wheat Stripe Rust, in Saskatchewan and Southern Alberta, Canada and Virulence Comparison with Races from the United States

Plant Disease ◽  
2016 ◽  
Vol 100 (8) ◽  
pp. 1744-1753 ◽  
Author(s):  
G. S. Brar ◽  
H. R. Kutcher
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
Stripe Rust ◽  
Great Plains ◽  
Puccinia Striiformis ◽  
The United States ◽  
Wheat Stripe Rust ◽  
The Pacific ◽  
Southern Alberta ◽  
Virulence Frequency

Wheat stripe rust, caused by Puccinia striiformis f. sp. tritici, has been common across Saskatchewan, Canada since 2000. Fifty-nine isolates of P. striiformis f. sp. tritici, the majority of which were collected between 2011 and 2013 from Saskatchewan and southern Alberta, were analyzed for virulence frequency and diversity and compared with isolates characterized in the Pacific Northwest and Great Plains regions of the United States. In all, 31 wheat differentials, including 20 near-isogenic lines and 1 triticale variety, differentiated 59 P. striiformis f. sp. tritici isolates into 33 races, of which one race, C-PST-1, represented 31% of the isolates. None of the races were virulent on Yr5, Yr15, or YrSP. Virulence frequency ranged from 65 to 98% on YrA, Yr2, Yr8, Yr9, Yr27, Yr29, Yr32, YrSu, ‘Heines VII’, and ‘Nord Deprez’. Race C-PST-6 was virulent on the greatest number of the differentials (n = 25) and C-PST-18 on the fewest (n = 14). Discriminant analysis of principal components and multivariate cluster analyses detected three and four major groups, respectively, which differed from each other in terms of virulence spectrum and year of collection. The diversity of the P. striiformis f. sp. tritici population in southern Alberta was greater than in Saskatchewan, which indicated that, although P. striiformis f. sp. tritici is primarily windborne over great distances and does not usually overwinter, there are detectable differences in virulence between these regions of western Canada. Comparative analyses of virulence frequency of Saskatchewan or southern Alberta isolates with isolates representing races from the Great Plains and the Pacific Northwest of the United States indicated greater similarity of Saskatchewan races to the Great Plains despite strong correlations with both parts of the United States. This suggests that the P. striiformis f. sp. tritici population in Saskatchewan is a mixture of inoculum from both parts of the United States.

scholarly journals Comparison of Virulence and Isozyme Phenotypes of Pgt-QCCJ and Great Plains Races of Puccinia graminis f. sp. tritici

1997 ◽  
Vol 87 (9) ◽  
pp. 910-914 ◽  
Author(s):  
A. P. Roelfs ◽  
B. McCallum ◽  
D. V. McVey ◽  
J. V. Groth
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
Great Plains ◽  
Stem Rust ◽  
The United States ◽  
Northern Great Plains ◽  
Puccinia Graminis ◽  
The Pacific ◽  
Sexual Recombination ◽  
Winter Wheat Cultivars

Stem rust race Pgt-QCCJ was first found in the Great Plains of the United States in 1989, collected primarily from barley. This race became a major part of the Puccinia graminis f. sp. tritici population, even though it is virulent to only a few hard red winter wheat cultivars in the central Great Plains and to barley in the northern Great Plains. It threatens barley production in the northern Great Plains of the United States and Canada due to virulence to Rpg-1. Six differences in virulence and two in isozyme banding patterns from the most similar stem rust races make it unlikely that QCCJ arose as a mutant. Thus, QCCJ likely arose through sexual or parasexual recombination. Sexual recombination in the Great Plains is unlikely, as it has not been detected in many years. Avirulence to ‘McNair 70l’ is only known from the Pacific Northwest of the United States and adjacent Canada. The rust population in this area is of sexual origin, and the pattern of virulence/avirulence and isozyme banding for QCCJ occurs there. Pgt-QCCJ likely originated in the Pacific Northwest during or before 1989 and was wind-transported into the Great Plains.

scholarly journals First record of Euxestonotus error (Hymenoptera: Platygastridae) in the Pacific Northwest, United States of America

2016 ◽  
Vol 148 (5) ◽  
pp. 616-618 ◽  
Author(s):  
E.R. Echegaray ◽  
R.N. Stougaard ◽  
B. Bohannon
Keyword(s):  
United States ◽  
New York ◽  
Pacific Northwest ◽  
United States Of America ◽  
First Record ◽  
The United States ◽  
Sitodiplosis Mosellana ◽  
Wheat Midge ◽  
The Pacific ◽  
Northwestern Montana

AbstractEuxestonotus error (Fitch) (Hymenoptera: Platygastridae) is considered part of the natural enemy complex of the wheat midge Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae). Although previously reported in the United States of America, there is no record for this species outside the state of New York since 1865. A survey conducted in the summer of 2015 revealed that E. error is present in northwestern Montana and is likely playing a role in the suppression of wheat midge populations.

“How Can We Catch Fire?”

2021 ◽  
pp. 119-143
Author(s):  
Melanie C. Ross
Keyword(s):  
United States ◽  
African American ◽  
Pacific Northwest ◽  
Holy Spirit ◽  
The United States ◽  
Kingdom Of God ◽  
The Pacific ◽  
The Holy Spirit ◽  
Influence At Work ◽  
Vineyard Movement

Chapter 5 explores the Vineyard movement, one of the fastest-growing church movements in the United States, which is committed to holding together the “already” and “not yet” of the Kingdom of God in worship. In addition to looking for a dramatic, miraculous inbreaking of the Holy Spirit, there is a less dramatic but equally formative influence at work in worship: the Quaker notion of “gospel order” and its accompanying understanding of ethics. These commitments are tested at “Koinonia Vineyard,” a congregation located in the Pacific Northwest, where one African American member wrestles with her vision of activism and her Caucasian pastor’s desire for the congregation to remain politically neutral during a time of national racial unrest.

Integrated Control of Rush Skeletonweed (Chondrilla juncea) in the Western U.S.

Weed Science ◽  
1986 ◽  
Vol 34 (S1) ◽  
pp. 2-6 ◽  
Author(s):  
Gary A. Lee
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
Integrated Control ◽  
Control Program ◽  
The United States ◽  
The Pacific ◽  
Rush Skeletonweed ◽  
Eurasian Species ◽  
Eastern Seaboard ◽  
Chondrilla Juncea

Rush skeletonweed (Chondrilla junceaL. CHOJU) infestations occur along the eastern seaboard and in several western states of the United States. This Eurasian species was inadvertently introduced prior to 1870, with established stands first reported in Maryland and West Virginia (16). These infestations (16) were assessed as lacking aggressive characteristics and posed little threat as a problem weed. Although rush skeletonweed was discovered in the Pacific Northwest as early as 1938, the species was not recognized as a potential weed problem until nearly three decades later (27). Subsequent surveys revealed that infestations occupied over 2.3 million ha in California, Idaho, Oregon, and Washington (6). Attempts to generate support for an organized control program in Idaho were met with little enthusiasm during the 1960's.

scholarly journals Primary Atmospheric Drivers of Pluvial Years in the United States Great Plains

2018 ◽  
Vol 19 (4) ◽  
pp. 643-658 ◽  
Author(s):  
Paul X. Flanagan ◽  
Jeffrey B. Basara ◽  
Jason C. Furtado ◽  
Xiangming Xiao
Keyword(s):  
United States ◽  
Great Plains ◽  
Heavy Precipitation ◽  
The United States ◽  
Precipitation Variability ◽  
Northern Great Plains ◽  
Southern Great Plains ◽  
The Public ◽  
Moisture Fluxes ◽  
Precipitation Events

Abstract Precipitation variability has increased in recent decades across the Great Plains (GP) of the United States. Drought and its associated drivers have been studied in the GP region; however, periods of excessive precipitation (pluvials) at seasonal to interannual scales have received less attention. This study narrows this knowledge gap with the overall goal of understanding GP precipitation variability during pluvial periods. Through composites of relevant atmospheric variables from the ECMWF twentieth-century reanalysis (ERA-20C), key differences between southern Great Plains (SGP) and northern Great Plains (NGP) pluvial periods are highlighted. The SGP pluvial pattern shows an area of negative height anomalies over the southwestern United States with wind anomalies consistent with frequent synoptic wave passages along a southward-shifted North Pacific jet. The NGP pattern during pluvial periods, by contrast, depicts anomalously low heights in the northwestern United States and an anomalously extended Pacific jet. Analysis of daily heavy precipitation events reveals the key drivers for these pluvial events, namely, an east–west height gradient and associated stronger poleward moisture fluxes. Therefore, the results show that pluvial years over the GP are likely driven by synoptic-scale processes rather than by anomalous seasonal precipitation driven by longer time-scale features. Overall, the results present a possible pathway to predicting the occurrence of pluvial years over the GP and understanding the causes of GP precipitation variability, potentially mitigating the threats of water scarcity and excesses for the public and agricultural sectors.

scholarly journals Genomic Variation and Evolution of Vibrio parahaemolyticus ST36 over the Course of a Transcontinental Epidemic Expansion

mBio ◽  
2017 ◽  
Vol 8 (6) ◽  
Author(s):  
Jaime Martinez-Urtaza ◽  
Ronny van Aerle ◽  
Michel Abanto ◽  
Julie Haendiges ◽  
Robert A. Myers ◽  
...  
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
Vibrio Parahaemolyticus ◽  
Evolutionary Process ◽  
The United States ◽  
Sequence Type ◽  
Evolutionary Divergence ◽  
Human Pathogens ◽  
The Pacific ◽  
Northeast Coast

ABSTRACT Vibrio parahaemolyticus is the leading cause of seafood-related infections with illnesses undergoing a geographic expansion. In this process of expansion, the most fundamental change has been the transition from infections caused by local strains to the surge of pandemic clonal types. Pandemic clone sequence type 3 (ST3) was the only example of transcontinental spreading until 2012, when ST36 was detected outside the region where it is endemic in the U.S. Pacific Northwest causing infections along the U.S. northeast coast and Spain. Here, we used genome-wide analyses to reconstruct the evolutionary history of the V. parahaemolyticus ST36 clone over the course of its geographic expansion during the previous 25 years. The origin of this lineage was estimated to be in ~1985. By 1995, a new variant emerged in the region and quickly replaced the old clone, which has not been detected since 2000. The new Pacific Northwest (PNW) lineage was responsible for the first cases associated with this clone outside the Pacific Northwest region. After several introductions into the northeast coast, the new PNW clone differentiated into a highly dynamic group that continues to cause illness on the northeast coast of the United States. Surprisingly, the strains detected in Europe in 2012 diverged from this ancestral group around 2000 and have conserved genetic features present only in the old PNW lineage. Recombination was identified as the major driver of diversification, with some preliminary observations suggesting a trend toward a more specialized lifestyle, which may represent a critical element in the expansion of epidemics under scenarios of coastal warming. IMPORTANCE Vibrio parahaemolyticus and Vibrio cholerae represent the only two instances of pandemic expansions of human pathogens originating in the marine environment. However, while the current pandemic of V. cholerae emerged more than 50 years ago, the global expansion of V. parahaemolyticus is a recent phenomenon. These modern expansions provide an exceptional opportunity to study the evolutionary process of these pathogens at first hand and gain an understanding of the mechanisms shaping the epidemic dynamics of these diseases, in particular, the emergence, dispersal, and successful introduction in new regions facilitating global spreading of infections. In this study, we used genomic analysis to examine the evolutionary divergence that has occurred over the course of the most recent transcontinental expansion of a pathogenic Vibrio, the spreading of the V. parahaemolyticus sequence type 36 clone from the region where it is endemic on the Pacific coast of North America to the east coast of the United States and finally to the west coast of Europe. IMPORTANCE Vibrio parahaemolyticus and Vibrio cholerae represent the only two instances of pandemic expansions of human pathogens originating in the marine environment. However, while the current pandemic of V. cholerae emerged more than 50 years ago, the global expansion of V. parahaemolyticus is a recent phenomenon. These modern expansions provide an exceptional opportunity to study the evolutionary process of these pathogens at first hand and gain an understanding of the mechanisms shaping the epidemic dynamics of these diseases, in particular, the emergence, dispersal, and successful introduction in new regions facilitating global spreading of infections. In this study, we used genomic analysis to examine the evolutionary divergence that has occurred over the course of the most recent transcontinental expansion of a pathogenic Vibrio, the spreading of the V. parahaemolyticus sequence type 36 clone from the region where it is endemic on the Pacific coast of North America to the east coast of the United States and finally to the west coast of Europe.

scholarly journals Verticillium Wilt in Spinach Seed Production

Plant Disease ◽  
2005 ◽  
Vol 89 (1) ◽  
pp. 4-11 ◽  
Author(s):  
Lindsey J. du Toit ◽  
Mike L. Derie ◽  
Pablo Hernandez-Perez
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
Seed Production ◽  
Verticillium Wilt ◽  
Spinacia Oleracea ◽  
Seed Transmission ◽  
The United States ◽  
Male And Female ◽  
Systemic Movement ◽  
The Pacific

There are no previous reports of Verticillium wilt in fresh and processing spinach (Spinacia oleracea) crops in the United States. In 2002, a hybrid spinach seed crop in the Pacific Northwest developed late-season wilt symptoms. Assays of the harvested seed and stock seed of the male and female parents revealed 59.5, 44.0, and 1.5%, respectively, were infected with Verticillium dahliae. Assays of 13 stock or commercial seed lots grown in 2002 and 62 commercial lots harvested in 2003 in Denmark, Holland, New Zealand, and the United States revealed the prevalence of Verticillium spp. in commercial spinach seed. Sixty-eight lots (89%) were infected with Verticillium spp. at incidences ranging from 0.3 to 84.8%. Five spinach seed isolates of V. dahliae were pathogenic on each of three spinach cultivars by root-dip inoculation. V. dahliae was detected on 26.4% of the seed from 7 of 11 inoculated plants but on none of the seed from 6 control plants, demonstrating systemic movement of V. dahliae. Seed-to-seed transmission was also demonstrated by planting naturally infected seed lots. This is the first report of Verticillium wilt of spinach in the primary region of spinach seed production in the United States.

scholarly journals An Analysis of the Prevalence of Heat Waves in the United States between 1948 and 2015

2018 ◽  
Vol 57 (7) ◽  
pp. 1535-1549 ◽  
Author(s):  
Evan M. Oswald
Keyword(s):  
United States ◽  
Heat Wave ◽  
Great Plains ◽  
Heat Waves ◽  
Estimation Method ◽  
The United States ◽  
Northern Great Plains ◽  
Strong Increase ◽  
Climate Data ◽  
Nighttime Temperatures

AbstractUnusually hot weather is a major concern to public health as well as other systems (e.g., ecological, economical, energy). This study utilized spatially continuous and homogenized observational surface climate data to examine changes in the regularity of heat waves in the continental United States. This included the examination of heat waves according only to daytime temperatures, nighttime temperatures, and both daytime and nighttime temperatures. Results confirmed a strong increase in the prevalence of heat waves between the mid-1970s and the dataset end (2015), and that increase was preceded by a mild decrease since the dataset beginning (1948). Results were unclear whether the prevalence of nighttime or simultaneous daytime–nighttime heat waves increased the most, but it was clear that increases were largest in the summer. The largest gains occurred in the West and Southwest, and a “warming hole” was most conspicuous in the northern Great plains. The changes in heat wave prevalence were similar to changes in the mean temperatures, and more so in the daytime heat waves. Daytime and nighttime heat waves coincided with one another more frequently in recent years than they did in the 1970s. Some parts of the United States (West Coast) were more likely than other parts to experience daytime and nighttime heat waves simultaneously. While linear trends were not sensitive to the climate dataset, trend estimation method, or heat wave definition, they were mildly sensitive to the start and end dates and extremely sensitive to the climate base period method (fixed in time or directly preceding any given heat wave).

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