scholarly journals The Intracloud Lightning Fraction in the Contiguous United States

2017 ◽  
Vol 145 (11) ◽  
pp. 4481-4499 ◽  
Author(s):  
Gina Medici ◽  
Kenneth L. Cummins ◽  
Daniel J. Cecil ◽  
William J. Koshak ◽  
Scott D. Rudlosky

This work addresses the long-term relative occurrence of cloud-to-ground (CG) and intracloud (IC; no attachment to ground) flashes for the contiguous United States (CONUS). It expands upon an earlier analysis by Boccippio et al. who employed 4-yr datasets provided by the U.S. National Lightning Detection Network (NLDN) and the Optical Transient Detector (OTD). Today, the duration of the NLDN historical dataset has more than tripled, and OTD data can be supplemented with data from the Lightning Imaging Sensor (LIS). This work is timely, given the launch of GOES-16, which includes the world’s first geostationary lightning mapper that will observe total lightning (IC and CG) over the Americas and adjacent ocean regions. Findings support earlier results indicating factor-of-10 variations in the IC:CG ratio throughout CONUS, with climatological IC fraction varying between 0.3 and greater than 0.9. The largest values are seen in the Pacific Northwest, central California, and where Colorado borders Kansas and Nebraska. An uncertainty analysis indicates that the large values in the northwest and central California are likely not due to measurement uncertainty. The high IC:CG ratio (>4) throughout much of Texas reported by Boccippio et al. is not supported by this longer-term climatology. There is no clear evidence of differences in IC fraction between land and coastal ocean. Lightning characteristics in six selected large regions show a consistent positive relationship between IC fraction and the percent of positive CG flashes, irrespective of lightning incidence (flash density), dominant season, or diurnal maximum period.

2016 ◽  
Vol 148 (5) ◽  
pp. 616-618 ◽  
Author(s):  
E.R. Echegaray ◽  
R.N. Stougaard ◽  
B. Bohannon

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.


2014 ◽  
Vol 21 (2) ◽  
pp. 594-604 ◽  
Author(s):  
Bryan A. Black ◽  
Jason B. Dunham ◽  
Brett W. Blundon ◽  
Jayne Brim-Box ◽  
Alan J. Tepley

2018 ◽  
Vol 19 (3) ◽  
pp. 258-264
Author(s):  
David H. Gent ◽  
Briana J. Claassen ◽  
Megan C. Twomey ◽  
Sierra N. Wolfenbarger

Powdery mildew (caused by Podosphaera macularis) is one of the most important diseases of hop in the western United States. Strains of the fungus virulent on cultivars possessing the resistance factor termed R6 and the cultivar Cascade have become widespread in the Pacific Northwestern United States, the primary hop producing region in the country, rendering most cultivars grown susceptible to the disease at some level. In an effort to identify potential sources of resistance in extant germplasm, 136 male accessions of hop contained in the U.S. Department of Agriculture collection were screened under controlled conditions. Iterative inoculations with three isolates of P. macularis with varying race identified 23 (16.9%) accessions with apparent resistance to all known races of the pathogen present in the Pacific Northwest. Of the 23 accessions, 12 were resistant when inoculated with three additional isolates obtained from Europe that possess novel virulences. The nature of resistance in these individuals is unclear but does not appear to be based on known R genes. Identification of possible novel sources of resistance to powdery mildew will be useful to hop breeding programs in the western United States and elsewhere.


2021 ◽  
pp. 119-143
Author(s):  
Melanie C. Ross

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.


2017 ◽  
Vol 8 (2) ◽  
pp. 640-647 ◽  
Author(s):  
Jeffrey C. Jolley ◽  
Christina T. Uh ◽  
Gregory S. Silver ◽  
Timothy A. Whitesel

Abstract Native lamprey populations are declining worldwide. In the Pacific Northwest focus on conservation and management of these ecologically and culturally important species has increased. Concern has emerged regarding the effects of sampling and handling of lamprey, with little to no attention given to the larval lifestage. We monitored the survival of larval Pacific Lamprey Entosphenus tridentatus and Lampetra spp. after backpack electrofishing, deepwater electrofishing and suction-pumping, anesthesia, and handling. We performed survival trials on wild-caught lamprey (n = 15 larvae in each trial) collected from the Clackamas River drainage in Oregon, USA, coupled with control group trials from lamprey sourced from a hatchery (n = 10 larvae). Short-term (96 h) survival was >98% with only one observed mortality. Delayed mortality (1 wk) was observed for four individuals that had fungus; two of those were positive for the bacteria Aeromonas hyrdrophila. We recorded blood hematocrit as a secondary measure of stress. The baseline, nonstressed larvae hematocrit levels did not differ from those of fish that had undergone stress through electrofishing, suction-pumping, and handling without anesthesia. Electrofishing, suction-pumping, and anesthesia showed no short-term negative effects on larval lamprey although potential long-term effects remain unstudied. These techniques appear to provide efficient and relatively safe methods for collecting and surveying larval lamprey.


Weed Science ◽  
1986 ◽  
Vol 34 (S1) ◽  
pp. 2-6 ◽  
Author(s):  
Gary A. Lee

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.


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