Evaluating Thunderstorm Outflow Boundaries in Complex Terrain

Rapid changes in wind and turbulence generated by thunderstorm gust fronts (GFs) can threaten the safety of wildland firefighters. Firefighters are particularly vulnerable to GFs in areas of complex terrain, where local terrain influence on GF winds can add complexity and tactical challenges faced by emergency management teams. Despite this, our traditional understanding of GF structure and behavior has focused primarily on GFs that develop from organized thunderstorms in flatter regions. In this dissertation, the investigation of GFs is broadened to those that occur in areas of complex terrain. First, Chapter 2 focuses on quantifying changes in vertical profiles of atmospheric variables during 24 GFs that occurred in the Colorado Front Range using in-situ and remote-sensing instruments. Second, in Chapter 3, GFs that were pushed uphill atop the crest of the Mogollon Rim in Arizona are statistically compared to those that propagated down into or along the Rio Grande Valley in New Mexico using in situ and radar observations. Lastly, in Chapter 4, idealized microburst and outflow boundaries are simulated using the Weather Research and Forecasting (WRF) model to quantify canyon-enhancement of winds and turbulence generated by microbursts. In Chapter 2, it was found that the magnitude change in GF characteristics were on average weaker in the Colorado Front Range GFs compared to what is typically observed along GFs from organized, severe storms in flatter regions. Most events from this study experienced an increase in wind speed from 1 to 8 m s-1, relative humidity from 1 to 8 %, and weak vertical motion from 0.3 to 3.6 m s-1 during GF passage, while temperature dropped by 0.2 to 3&deg; C and ii turbulent kinetic energy (TKE) peaked at &gt; 4 m2 s-2. Vertical profiles reveal that these changes vary little with height in the lowest 300 m. In Chapter 3, GFs that propagated down into and along the Rio Grande Valley in NM were associated with faster propagation speeds (pspd= 8.6 m s-1), slightly larger decreases in temperature (∆T = -2.2&deg;C), larger increases in horizontal wind speeds (∆wsp= 7.5 m s-1) and changes in wind direction (∆wdr = 76.5&deg;) compared to GFs that reached the crest of the Mogollon Rim in Arizona (pspd = 5.2 m s-1; ∆T = -1.5&deg;C; ∆wsp= 3.5 m s-1; ∆wdir = 53.1&deg;). GFs atop the Mogollon Rim in Arizona behaved less in accordance with density current theory compared to those in the Rio Grande Valley in New Mexico. In Chapter 4, short-distance microbursts produced stronger canyon-induced enhancements in horizontal wind, upward vertical velocity, and TKE in the canyons and along the canyon walls compared to long-distance microbursts, which were located ~2 km farther away. For canyons located closer to the microburst, the increase in horizontal winds, vertical velocity, and TKE was generally stronger in the canyon and along the walls of the steeper 30&deg; sloped canyons compared to the 10&deg; sloped canyons. Lastly, the maximum increase in horizontal wind is mostly observed near the canyon floors and towards the exit region of the canyons regardless of the proximity to the microburst. Conversely, the maximum increase in upward vertical velocity and TKE is mostly observed at higher elevations on the walls and along the canyon crests in both short- and long-distance canyons.</p

Climate Change and the Sea Breeze in the North Carolina Coast

Forecasting SB genesis and evolution is often a difficult task for coastal meteorologists. This is especially the case when attempting to forecast SB-induced precipitation, as not every SB front induces rainfall. The two primary objectives in this thesis were to 1) study why some SB fronts induce precipitation while others do not, and 2) to explore the effects of a future warmer climate on SB evolution. To explore these objectives, a SB climatology for 2009-2012 along the NC coast was constructed using radar and reanalysis datasets. Additionally, current and future climate SB simulations were produced using the Weather Research and Forecasting (WRF) model. Future climate WRF simulations utilized the pseudo-global warming (PGW) approach, which involves rerunning current climate SB simulations using modified thermodynamic initial conditions that represent a warmer, late 21st century climate. The 88 SB events that were detected between 2009-2012 were nearly evenly distributed into SB dry (53%) and SB wet (47%) events. Significant differences in kinematic and thermodynamic conditions were present during SB dry and wet events. On average, SB dry events occurred under stronger synoptic-scale winds (6.00 ± 2.36 m/s), while SB wet events occurred under lighter synoptic-scale winds (4.02 ± 2.16 m/s). Moreover, most (85%) SB events occur during offshore (53%) or parallel (22%) flow. However, as is the case throughout the literature, the maximization of SB fronts during offshore synoptic flow is sensitive to the synoptic wind speed. SB events that occurred under offshore synoptic-scale flow in the 0 to 4-6 m/s range were more likely to be categorized as SB wet events, while SB events that occurred under offshore synoptic-scale flow above 0 to 4-6 m/s were more likely to be categorized as SB dry events, results similar to those seen in the literature. In terms of thermodynamic controls, results from this climatology show that the atmosphere has larger values of CAPE and lower values of CIN and is therefore more conducive to deep convection on SB wet than on SB dry event days. This study suggests that favorable conditions for the formation of precipitation along the SB include enhanced early morning instability, minimal stable air aloft, and synoptic-scale offshore wind flow with speeds between 0 and 4-6 m/s throughout the duration of the event. Seven of the observed SB precipitation events were simulated in WRF under current climate conditions and repeated for future climate conditions under the RCP 4.5 and RCP 8.5 scenarios. Under current climate conditions WRF performed well in simulating the horizontal extent and late day veering/backing of the SB front, as well as the timing of initiation and peak SB-induced precipitation. However, it struggled to simulate the inland penetration distance of the SB front, as well as the spatial distribution and total accumulation of precipitation along the SB front. Under future climate conditions the evolution of WRF simulated SB fronts was altered resulting in some future SB fronts that induced more precipitation, while other future SB fronts induced less precipitation when compared to the current climate WRF simulations. Additionally, under future climate conditions the inland penetration timing and distance was altered for all of these SB cases when compared to the current climate WRF simulations. In both the current and future climate simulations the synoptic-dynamic shifts in the atmospheric flow appear to have more of an influence on SB evolution and associated precipitation than enhanced temperatures, moisture content, and instability. Subtle shifts in the synoptic-scale wind direction and speeds along the coast, associated with a westward migration of the North Atlantic Subtropical High's western ridge, had considerable influence on the amount and spatial distribution of future climate SB-induced precipitation. From a climatological perspective, the results herein suggest that understanding the effects of climate change on mesoscale precipitation patterns is a very complex task. From a forecasting perspective, the results presented herein suggest that subtle kinematic and thermodynamic shifts in the atmosphere will influence NC SB evolution in both the current and future climate

Quantifying microburst wind and turbulence enhancement in canyons

Thunderstorms in arid and semi-arid regions like the U.S. intermountain west are often associated with dry microbursts. These microbursts are caused by evaporating precipitation in dry environments causing strong and difficult-to-observe cold outflow boundaries associated with rapid changes in wind and turbulence. A particularly dangerous situation can occur when microburst outflow winds are terrain-channeled into and within canyons during ongoing wildfire events, creating complex tactical challenges for firefighters and emergency managers. Given the dangers to firefighters by unpredictable microbursts and outflow boundaries within canyons, this paper quantifies the canyon-enhancement of wind and turbulence from microburst outflow boundaries using idealized large eddy simulations from the Weather Research and Forecasting (WRF) model. A series of simulations were conducted with the center of microburst downdrafts were placed 1.3 and 3.3 km upwind of a series of canyon types differing in length and slope angle.&nbsp;These canyon simulations are compared to microburst outflow boundary characteristics in flat terrain deriving topographic multiplier and differences in&nbsp;horizontal winds (wsp), upward vertical velocity (w), and turbulence kinetic energy (TKE).&nbsp;The increase in these variables is larger when the microburst is closer to the canyon and for steeper canyon walls generating increase in&nbsp;wsp&nbsp;by 4.5-6.6 m s-1,&nbsp;w&nbsp;by 1.9-8.4 m s-1,&nbsp;TKE&nbsp;by 1.4-6.6 m2&nbsp;s-2.&nbsp;&nbsp;The topographic multiplier for horizontal winds is 0.1-0.2 times higher within the long-distance canyons compared to the short-distance canyons. &nbsp; Branko Kosović, National Center for Atmospheric Research, Boulder, Colorado Luchetti, Nicholas, National Weather Service, Raleigh, North Carolina Friedrich, Katja, Atmospheric and Oceanic Sciences (ATOC), University of Colorado Boulder, Boulder, Colorado</p

Influencia del Anticiclón del Atlántico Norte en la pluviosidad de la brisa marina en Carolina del Norte, Estados Unidos

The sea-breeze (SB) is an important source of summertime precipitation in North Carolina (NC, southeast United States). However, not all SB events produce precipitation. A climatology of wet and dry SB events in NC is used to investigate the conditions that are conducive to precipitation associated with the sea breeze. Radar imagery was used to detect 88 SB events that occurred along the NC coast between May-September of 2009-2012. The majority (85%) of SB events occurred during offshore flow (53%) or during flow that was parallel to the coast (22%). SB events were separated into dry (53%) and wet (47%) events and differences in the dynamic and thermodynamic parameters of the environment in which they formed were analyzed. Significant differences in dynamic and thermodynamic conditions were found. SB dry events occurred under stronger winds (6.00 ± 2.36 ms-1) than SB wet events (4.02 ± 2.16 ms-1). Moreover, during SB wet events larger values of convective available potential energy and lower values of convective inhibition were present, conditions that favor precipitation. Overall, the SB wet events accounted for 20-30% of the May-September precipitation along the NC coastal region. The position of the North Atlantic Subtropical High (NASH) controls both moisture availability and winds along the NC coast, thus providing a synoptic-scale control mechanism for SB precipitation. In particular, it was shown that when the NASH western ridge is located along the southeast coast of the United States, it causes a moist southwesterly flow along the NC coast that may favor the occurrence of SB wet events.La brisa marina (BM) es una importante fuente de precipitación de verano en Carolina del Norte (NC en su sigla en inglés), sudeste de Estados Unidos. Sin embargo, no todos los eventos de BM producen precipitación. En este trabajo se utiliza una climatología de eventos de BM lluviosos y secos en NC para investigar las condiciones que conducen a la precipitación. Se utilizaron imágenes de radar para detectar 88 eventos de BM ocurridos a lo largo de la costa NC entre mayo y septiembre de 2009 a 2012. La mayoría (85%) de los eventos de BM ocurrieron durante períodos de viento hacia el mar (53%) o viento paralelo a la costa (22%). Los eventos BM se separaron en eventos secos (53%) y lluviosos (47%) y se analizaron las diferencias en los parámetros dinámicos y termodinámicos del entorno en el que se formaron. Se encontraron diferencias significativas en las condiciones dinámicas y termodinámicas. Eventos de BM secos ocurrieron bajo vientos más fuertes (6,00 ± 2,36 ms-1) que los eventos de BM lluviosos (4,02 ± 2,16 ms-1). Las BM lluviosas ocurrieron bajo valores de energía potencial convectiva disponible más altos y valores del parámetro de inhibición convectiva más bajos, condiciones que favorecen la lluvia. En general, los eventos de BM lluviosos representaron el 20-30% de la precipitación a lo largo de la región costera de NC de mayo a septiembre. La posición de la Alta Subtropical del Atlántico Norte (ASAN) controla la disponibilidad de humedad y los vientos a lo largo de la costa de NC, proporcionando así un mecanismo de control de escala sinóptica para la precipitación de la BM. En particular, cuando la cresta occidental de la ASAN se localiza a lo largo de la costa sureste de los Estados Unidos, se produce un flujo de sudoeste húmedo a lo largo de la costa NC que puede favorecer la ocurrencia de eventos de BM lluviosos.This project was partially funded by the Climate and Large-Scale Dynamics and the Physical and Dynamic Meteorology programs of the National Science Foundation’s Division of Atmospheric and Geospatial Sciences, Award AGS-1118141

Comprehensive Cancer-Predisposition Gene Testing in an Adult Multiple Primary Tumor Series Shows a Broad Range of Deleterious Variants and Atypical Tumor Phenotypes.

Multiple primary tumors (MPTs) affect a substantial proportion of cancer survivors and can result from various causes, including inherited predisposition. Currently, germline genetic testing of MPT-affected individuals for variants in cancer-predisposition genes (CPGs) is mostly targeted by tumor type. We ascertained pre-assessed MPT individuals (with at least two primary tumors by age 60 years or at least three by 70 years) from genetics centers and performed whole-genome sequencing (WGS) on 460 individuals from 440 families. Despite previous negative genetic assessment and molecular investigations, pathogenic variants in moderate- and high-risk CPGs were detected in 67/440 (15.2%) probands. WGS detected variants that would not be (or were not) detected by targeted resequencing strategies, including low-frequency structural variants (6/440 [1.4%] probands). In most individuals with a germline variant assessed as pathogenic or likely pathogenic (P/LP), at least one of their tumor types was characteristic of variants in the relevant CPG. However, in 29 probands (42.2% of those with a P/LP variant), the tumor phenotype appeared discordant. The frequency of individuals with truncating or splice-site CPG variants and at least one discordant tumor type was significantly higher than in a control population (χ2 = 43.642; p ≤ 0.0001). 2/67 (3%) probands with P/LP variants had evidence of multiple inherited neoplasia allele syndrome (MINAS) with deleterious variants in two CPGs. Together with variant detection rates from a previous series of similarly ascertained MPT-affected individuals, the present results suggest that first-line comprehensive CPG analysis in an MPT cohort referred to clinical genetics services would detect a deleterious variant in about a third of individuals.JW is supported by a Cancer Research UK Cambridge Cancer Centre Clinical Research Training Fellowship. Funding for the NIHR BioResource – Rare diseases project was provided by the National Institute for Health Research (NIHR, grant number RG65966). ERM acknowledges support from the European Research Council (Advanced Researcher Award), NIHR (Senior Investigator Award and Cambridge NIHR Biomedical Research Centre), Cancer Research UK Cambridge Cancer Centre and Medical Research Council Infrastructure Award. The University of Cambridge has received salary support in respect of EM from the NHS in the East of England through the Clinical Academic Reserve. The views expressed are those of the authors and not necessarily those of the NHS or Department of Health. DGE is an NIHR Senior Investigator and is supported by the all Manchester NIHR Biomedical Research Centre

Quantifying microburst wind and turbulence enhancement in canyons

This data set contains model output from NCARS's Weather and Research Forecasting(WRF) model run in large-eddy simulation (LES) mode (WRF v3.6).&nbsp;A series of idealized simulations were conducted with the center of microburst downdrafts were placed 1.3 and 3.3 km upwind of a series of canyon types differing in length and slope angle. These canyon simulations are compared to microburst outflow boundary characteristics in flat terrain deriving topographic multiplier and differences in horizontal winds (wsp), upward vertical velocity (w), and turbulence kinetic energy (TKE). This data set is associated with a journal publication by &nbsp;Luchetti et al. submitted to Monthly Weather Review in September 2021.&nbsp;The WRF model code (https://doi.org/10.5065/D6MK6B4K,&nbsp;Skamarock et al.,&nbsp;2008) is publicly available at&nbsp;http://www2.mmm.ucar.edu/wrf/users/&nbsp;(last access: 11&nbsp;June&nbsp;2020). Model output data for hours 6-7 h and analysis code including namelist.input, input soundings, and auxiliary terrain netcdf files needed to run the simulations and create the figures are located at https://github.com/nluchett/wrf_canyon_experiment.</p

Climate Change and the Sea Breeze in the North Carolina Coast

Forecasting SB genesis and evolution is often a difficult task for coastal meteorologists. This is especially the case when attempting to forecast SB-induced precipitation, as not every SB front induces rainfall. The two primary objectives in this thesis were to 1) study why some SB fronts induce precipitation while others do not, and 2) to explore the effects of a future warmer climate on SB evolution. To explore these objectives, a SB climatology for 2009-2012 along the NC coast was constructed using radar and reanalysis datasets. Additionally, current and future climate SB simulations were produced using the Weather Research and Forecasting (WRF) model. Future climate WRF simulations utilized the pseudo-global warming (PGW) approach, which involves rerunning current climate SB simulations using modified thermodynamic initial conditions that represent a warmer, late 21st century climate. The 88 SB events that were detected between 2009-2012 were nearly evenly distributed into SB dry (53%) and SB wet (47%) events. Significant differences in kinematic and thermodynamic conditions were present during SB dry and wet events. On average, SB dry events occurred under stronger synoptic-scale winds (6.00 ± 2.36 m/s), while SB wet events occurred under lighter synoptic-scale winds (4.02 ± 2.16 m/s). Moreover, most (85%) SB events occur during offshore (53%) or parallel (22%) flow. However, as is the case throughout the literature, the maximization of SB fronts during offshore synoptic flow is sensitive to the synoptic wind speed. SB events that occurred under offshore synoptic-scale flow in the 0 to 4-6 m/s range were more likely to be categorized as SB wet events, while SB events that occurred under offshore synoptic-scale flow above 0 to 4-6 m/s were more likely to be categorized as SB dry events, results similar to those seen in the literature. In terms of thermodynamic controls, results from this climatology show that the atmosphere has larger values of CAPE and lower values of CIN and is therefore more conducive to deep convection on SB wet than on SB dry event days. This study suggests that favorable conditions for the formation of precipitation along the SB include enhanced early morning instability, minimal stable air aloft, and synoptic-scale offshore wind flow with speeds between 0 and 4-6 m/s throughout the duration of the event. Seven of the observed SB precipitation events were simulated in WRF under current climate conditions and repeated for future climate conditions under the RCP 4.5 and RCP 8.5 scenarios. Under current climate conditions WRF performed well in simulating the horizontal extent and late day veering/backing of the SB front, as well as the timing of initiation and peak SB-induced precipitation. However, it struggled to simulate the inland penetration distance of the SB front, as well as the spatial distribution and total accumulation of precipitation along the SB front. Under future climate conditions the evolution of WRF simulated SB fronts was altered resulting in some future SB fronts that induced more precipitation, while other future SB fronts induced less precipitation when compared to the current climate WRF simulations. Additionally, under future climate conditions the inland penetration timing and distance was altered for all of these SB cases when compared to the current climate WRF simulations. In both the current and future climate simulations the synoptic-dynamic shifts in the atmospheric flow appear to have more of an influence on SB evolution and associated precipitation than enhanced temperatures, moisture content, and instability. Subtle shifts in the synoptic-scale wind direction and speeds along the coast, associated with a westward migration of the North Atlantic Subtropical High's western ridge, had considerable influence on the amount and spatial distribution of future climate SB-induced precipitation. From a climatological perspective, the results herein suggest that understanding the effects of climate change on mesoscale precipitation patterns is a very complex task. From a forecasting perspective, the results presented herein suggest that subtle kinematic and thermodynamic shifts in the atmosphere will influence NC SB evolution in both the current and future climate

Personality pathways to mortality: Interleukin-6 links conscientiousness to mortality risk

Personality is associated consistently with mortality hazards, but the physiological pathways are not yet clear. Immune system dysregulation may be one such pathway due to its role in age-related morbidity and mortality. In this preregistered study, we tested whether interleukin-6 (IL-6) and C-reactive protein (CRP) mediated the as sociations between personality traits and mortality hazards. The sample included 957 participants (M ± SD = 58.65 ± 11.51 years; range = 35–86 years) from the Midlife in the United States Survey that had 14 years of follow-up. Higher conscientiousness was associated with lower mortality hazards, with each one standard de viation higher conscientiousness associated with a 35% lower mortality risk. IL-6, but not CRP, partially mediated this association, with IL-6 accounting for 18% of this association in the fully adjusted model. While there was initial evidence that the biomarkers mediated both neuroticism and agreeableness and mortality risk, the indirect effects were not significant when controlling for the sociodemographic variables. Taken together, higher conscientiousness may lead to a longer life partially as a result of lower IL-6. This work highlights the importance of biological pathways that link personality to future mortality risk

Wittig derivatization of sesquiterpenoid polygodial leads to cytostatic agents with activity against drug resistant cancer cells and capable of pyrrolylation of primary amines

Many types of cancer, including glioma, melanoma, non-small cell lung cancer (NSCLC), among others, are resistant to proapoptotic stimuli and thus poorly responsive to current therapies based on the induction of apoptosis in cancer cells. The current investigation describes the synthesis and anticancer evaluation of unique C12-Wittig derivatives of polygodial, a sesquiterpenoid dialdehyde isolated from Persicaria hydropiper (L.) Delabre. These compounds were found to undergo an unprecedented pyrrole formation with primary amines in a chemical model system, a reaction that could be relevant in the biological environment and lead to the pyrrolation of lysine residues in the target proteins. The anticancer evaluation of these compounds revealed their promising activity against cancer cells displaying various forms of drug resistance, including resistance to proapoptotic agents. Mechanistic studies indicated that compared to the parent polygodial, which displays fixative general cytotoxic action against human cells, the C12-Wittig derivatives exerted their antiproliferative action mainly through cytostatic effects explaining their activity against apoptosis-resistant cancer cells. The possibility for an intriguing covalent modification of proteins through a novel pyrrole formation reaction, as well as useful activities against drug resistant cancer cells, make the described polygodial-derived chemical scaffold an interesting new chemotype warranting thorough investigation.SCOPUS: ar.jinfo:eu-repo/semantics/publishe