scholarly journals Spatial and Temporal Patterns of Thunderstorm Events that Produce Cloud-to-Ground Lightning in the Interior Southeastern United States

2005 ◽  
Vol 133 (6) ◽  
pp. 1417-1430 ◽  
Author(s):  
Mark S. Murphy ◽  
Charles E. Konrad
Keyword(s):  
United States ◽  
Spatial Pattern ◽  
Spatial Scales ◽  
Southeastern United States ◽  
Regional Scale ◽  
Radial Distance ◽  
Temporal Patterns ◽  
Study Region ◽  
Early Afternoon ◽  
Cg Lightning

Abstract Cloud-to-ground (CG) lightning data are used in this study to trace the daily patterns of thunderstorms in time and space across the topographically diverse southeastern United States. Four reoccurring patterns of thunderstorms (i.e., local, multilocal, regional, and widespread) are identified on the basis of the size of the region of CG lightning as well as the spatial pattern of the flashes within this region. To identify these patterns, hourly maps of CG flashes are produced over five summer seasons (June–August) and used to identify thunderstorm events on all days in which at least one CG lightning is observed. Thunderstorm events are defined by a temporally and spatially clustered hourly pattern of lightning flashes. The spatial pattern of lightning associated with each event is examined during the hour in which the flash density is the highest and is used to classify the event. The geographical and temporal patterns of each thunderstorm type are described. Also, flash densities are calculated at spatial scales ranging from 1- to 100-km radial distance. Over half of the identified thunderstorm events in the study were confined to the local scale and contained relatively few flashes. They were most common early in the morning and in the mountainous portions of the study area. Widespread events, on the other hand, showed a dense coverage of flashes within a given hour over a majority of the area. Although they occurred much less frequently (i.e., once every 8 days across most locales), they were responsible for the highest number of CG lightning flashes in the study region; furthermore, they produced the highest flash densities, both at the local and regional scale. A radar echo classification revealed that these events were not tied to mesoscale convective systems, but rather to the early afternoon development of numerous convective cell clusters and lines across the study area.

scholarly journals Evidence for Sexual Reproduction: Identification, Frequency, and Spatial Distribution of Venturia effusa (Pecan Scab) Mating Type Idiomorphs

2018 ◽  
Vol 108 (7) ◽  
pp. 837-846 ◽  
Author(s):  
Carolyn A. Young ◽  
Clive H. Bock ◽  
Nikki D. Charlton ◽  
Chakradhar Mattupalli ◽  
Nick Krom ◽  
...  
Keyword(s):  
United States ◽  
Mating Type ◽  
Spatial Scales ◽  
Southeastern United States ◽  
Draft Genome ◽  
Apple Scab ◽  
Hypothetical Protein ◽  
Sexual Stage ◽  
Pecan Scab ◽  
Conserved Genes

Venturia effusa (syn. Fusicladium effusum), causal agent of pecan scab, is the most prevalent pathogen of pecan (Carya illinoinensis), causing severe yield losses in the southeastern United States. V. effusa is currently known only by its asexual (conidial) stage. However, the degree and distribution of genetic diversity observed within and among populations of V. effusa are typical of a sexually reproducing fungal pathogen, and comparable with other dothideomycetes with a known sexual stage, including the closely related apple scab pathogen, V. inaequalis. Using the mating type (MAT) idiomorphs from V. inaequalis, we identified a single MAT gene, MAT1-1-1, in a draft genome of V. effusa. The MAT1-1-1 locus is flanked by two conserved genes encoding a DNA lyase (APN2) and a hypothetical protein. The MAT locus spanning the flanking genes was amplified and sequenced from a subset of 14 isolates, of which 7 contained MAT1-1-1 and the remaining samples contained MAT1-2-1. A multiplex polymerase chain reaction screen was developed to amplify MAT1-1-1, MAT1-2-1, and a conserved reference gene encoding β-tubulin, and used to screen 784 monoconidial isolates of V. effusa collected from 11 populations of pecan across the southeastern United States. A hierarchical sampling protocol representing region, orchard, and tree allowed for analysis of MAT structure at different spatial scales. Analysis of this collection revealed the frequency of the MAT idiomorphs is in a 1:1 equilibrium of MAT1-1:MAT1-2. The apparent equilibrium of the MAT idiomorphs provides impetus for a renewed effort to search for the sexual stage of V. effusa. [Formula: see text] Copyright © 2018 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

scholarly journals CO2 Storage Potential Reconnaissance of the Newly Identified Red Beds of Hazlehurst in the Southeastern United States

2021 ◽  
Vol 9 ◽  
Author(s):  
Ruoshi Cao ◽  
James Knapp ◽  
Prem Bikkina ◽  
Richard Esposito
Keyword(s):  
United States ◽  
South Carolina ◽  
Co2 Storage ◽  
Southeastern United States ◽  
Regional Scale ◽  
Depositional Environments ◽  
Point Sources ◽  
Red Beds ◽  
Specific System ◽  
Capillary Trapping

The states of Georgia and South Carolina emitted ∼100 million tons (Mt) of CO2 in 2019 from point sources. Integration and interpretation of subsurface data enabled identification of a previously unrecognized, regionally extensive, and thick (up to 450 m) sedimentary sequence—the Red beds of Hazlehurst (RbH)—as a potential saline reservoir for CO2 storage in the southeastern United States. Based on the renewed stratigraphic framework and structural interpretation of the RbH interval, we analyzed detailed well logs and the depositional environments to provide reconnaissance-level regional scale estimations of the storage resource. The volumetric results suggest the effective storage area (∼85,000 km2) has a maximum resource potential for 390 gigatons (Gt) of anthropogenic CO2. Petrophysical measurements suggest the permeability of RbH ranges from 0.001 to 48 mD, and the porosity ranges from 11.1 to 18.4%. Residual/capillary trapping and solubility trapping act as the main trapping mechanisms for long term storage and prevent vertical migration of CO2 into the shallow freshwater aquifers. Due to the heterogeneity observed in geophysical logs and the scarcity of well penetrations, future data collection is needed to characterize the storage aquifer and confining aquitards of a site-specific system at this stage.

scholarly journals Regional-scale management maps for forested areas of the Southeastern United States and the US Pacific Northwest

2018 ◽  
Vol 5 (1) ◽  
Author(s):  
Matthew Marsik ◽  
Caroline G. Staub ◽  
William J. Kleindl ◽  
Jaclyn M. Hall ◽  
Chiung-Shiuan Fu ◽  
...  
Keyword(s):  
United States ◽  
Pacific Northwest ◽  
Southeastern United States ◽  
Regional Scale ◽  
The Us ◽  
Forested Areas ◽  
Scale Management

scholarly journals Roles of Dynamic Forcings and Diabatic Heating in Summer Extreme Precipitation in East China and the Southeastern United States

2019 ◽  
Vol 32 (18) ◽  
pp. 5815-5831 ◽  
Author(s):  
Ji Nie ◽  
Bowen Fan
Keyword(s):  
United States ◽  
Extreme Precipitation ◽  
Large Scale ◽  
Diabatic Heating ◽  
Southeastern United States ◽  
Regional Scale ◽  
East China ◽  
Extreme Precipitation Events ◽  
Vorticity Advection ◽  
Moisture Advection

AbstractExtratropical regional-scale extreme precipitation events (EPEs) are usually associated with certain synoptic perturbations superimposed on slow-varying background circulations. These perturbations induce a dynamically forced ascent that destabilizes the atmospheric stratification and stimulates deep convection, which further drives the perturbation by releasing latent heat. This study identifies the characteristics of large-scale perturbations associated with summer EPEs in two representative regions, East China (ECN) and the southeastern United States (SUS), and analyzes the roles of dynamic forcings and diabatic heating using the quasigeostrophic omega equation. Composites of 39 events in each region show that the upper-level absolute vorticity advection and tropospheric warm advection promote dynamically forced ascent in EPEs, and the moisture advection premoistens the local environment. The background circulation and synoptic perturbations in ECN and the SUS have significant differences. The background vorticity, temperature, and moisture advection form the quasi-steady mei-yu front in ECN, which provides favorable conditions for heavy rainfall. In the SUS, weaker background ascents are forced mainly through vorticity advection. In the synoptic scale, the EPEs in ECN are triggered by short-wavelength wave trains, and in the SUS the EPEs are triggered by longer wavelength potential vorticity intrusions. Although the amplitudes of the dynamically forced ascent in the two regions are similar, diabatic heating contributes much more to the vertical motion in ECN than the SUS, which indicates that there is stronger diabatic heating feedback there. The stronger diabatic heating feedback in ECN appears to be due to stronger moisture advection, convective environments with more humidity, and stronger coupling between convection and large-scale dynamics.

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