bluuebunny/crossref_metadata_2025 huggingface dataset:
Atos de profanação
Authors: Fernandes Sílvia
Published: August 2020

Este artigo analisa as últimas criações de Janaína Leite feitas ao longo da década de 2010. Conversas com meu pai, estreado em 2014, e especialmente Stabat Mater, apresentado pela primeira vez, ainda em processo de criação, em 2019, são índices da radical trajetória da artista, e refletem uma série de experimentos cênicos e políticos recorrentes em uma parcela do teatro brasileiro do século XXI.
Kantan – Travesseiro dos sonhos de Yukio Mishima
Authors: Pinheiro Kimiko Uchigasaki , Reis Maria Da Glória Magalhães dos
Published: August 2020

O presente artigo apresenta a tradução da peça Kantan - Travesseiro dos sonhos de Yukio Mishima realizada para tese de douramento no Programa de Pós-graduação em Estudos Literários da Universidade de Brasília com a colaboração da professora Tae Suzuki, dos participantes do grupo de pesquisa Literatura, Educação e Dramaturgias Contemporâneas e do coletivo teatral Na classe e em cena.
Carta de 23 de abril de Matthias Langhoff a Nicolas Royer, diretor do Espace des Arts, Scène nationale, Chalon-sur-Saône
Authors: Langhoff Matthias , Royer Nicolas
Published: August 2020

Carta de 23 de abril de Matthias Langhoff a Nicolas Royer, diretor do Espaço das Artes, Cena Nacional, Chalon-sur-Saône
A extensão da imunidade tributária a sociedade de economia mista que presta serviços públicos
Authors: Carrijo Artur De Sousa
Published: August 2020

O presente trabalho discutiu os critérios para a identificação do regime jurídico ap licável às empresas estatais a p artir de um caso concreto ainda em julgam ento p elo Supremo Tribunal Federal. O objetivo central foi identificar se há imprecisão no uso de categorias fundamentais para a com preensão do tema, bem com o se os parâmetros adotados na decisão são aptos a nortear decisões futuras. Foram adotadas técnicas metodológicas conceituais e normativas no desenvolvimento do referencial teórico e no estudo normativo-jurídico do fenômeno para a análise do caso selecionado para estudo. Identificou-se, em especial, que a noção de serviços públicos e dos mecanism os e institutos de atuação descentralizada do Estado para a prestação de serviços públicos ou para a exploração de atividades econômicas são usadas de forma imprecisa. Concluiu-se, nesse sentido, que apesar da im precisão nos conceitos, parece haver a indicação de que a Suprem a Corte está retomando a compreensão de que a empresa estatal é uma escolha legítima da Administração e da qual decorre um regime jurídico que não deve ser transfigurado, em contraposição com os precedentes anteriores.
Notas sobre a história das prisões do Estado de São Paulo
Authors: Garcia Liliane Klein
Published: August 2020

O presente artigo busca produzir uma curta compilação da história da execução da pena de prisão em estabelecimentos no território do atual estado de São Paulo, ressaltando acontecimentos que alteraram a forma com a qual o governo e a sociedade pensam o ato de punir e as formas aceitáveis de o fazer. São pontuadas evoluções administrativas e da atenção ao detento desde o período colonial, passando pelo Império e pela República, ressaltando a tendência circular de períodos de humanização e recrudescimento da política penitenciária. Conclui-se que o atual momento político no estado favorece uma mudança do paradigma presente desde 2007.
Limites do controle do TCU sobre os atos discricionários das agências reguladoras
Authors: Rocha Heloisa Rodrigues da
Published: August 2020

O presente artigo pretende analisar os limites do controle externo realizado pelo Tribunal de Contas da União (TCU) sobre os atos administrativos discricionários das agências reguladoras. Observa-se que esse conceito de discricionariedade evoluiu durante os três últimos séculos no Brasil. Desde o século XIX e até hoje, há quem defenda a impossibilidade do controle externo, judicial ou administrativo, sobre o mérito desses atos. Por outro lado, há quem defenda que não podem existir atos não sujeitos a qualquer tipo de controle. Análises empíricas e normativas demonstram que o TCU segue a teoria majoritária moderna, que permite o controle dos atos dentro de certos limites. Assim, apesar de existir um espaço de discricionariedade para a tomada de algumas decisões pelos gestores, é imprescindível que tais atos obedeçam aos limites legais e constitucionais, visando proteger a força normativa da Constituição e a própria Democracia.
Impact of the Vulnerable Preterm Heart and Circulation on Adult Cardiovascular Disease Risk
Authors: Lewandowski Adam J. , Levy Philip T. , Bates Melissa L. , McNamara Patrick J. , Nuyt Anne Monique , Goss Kara N.
Published: August 2020

Preterm birth accounts for over 15 million global births per year. Perinatal interventions introduced since the early 1980s, such as antenatal glucocorticoids, surfactant, and invasive ventilation strategies, have dramatically improved survival of even the smallest, most vulnerable neonates. As a result, a new generation of preterm-born individuals has now reached early adulthood, and they are at increased risk of cardiovascular diseases. To better understand the sequelae of preterm birth, cardiovascular follow-up studies in adolescents and young adults born preterm have focused on characterizing changes in cardiac, vascular, and pulmonary structure and function. Being born preterm associates with a reduced cardiac reserve and smaller left and right ventricular volumes, as well as decreased vascularity, increased vascular stiffness, and higher pressure of both the pulmonary and systemic vasculature. The purpose of this review is to present major epidemiological evidence linking preterm birth with cardiovascular disease; to discuss findings from clinical studies showing a long-term impact of preterm birth on cardiac remodeling, as well as the systemic and pulmonary vascular systems; to discuss differences across gestational ages; and to consider possible driving mechanisms and therapeutic approaches for reducing cardiovascular burden in individuals born preterm.
Clinical evaluation of the use of laryngeal tube versus laryngeal mask airway for out-of-hospital cardiac arrest by paramedics in Singapore
Authors: Chan JJ , Goh ZX , Koh ZX , Soo JJE , Fergus J , Ng YY , Allen JC Jr , Ong MEH
Published: August 2020

INTRODUCTION It remains unclear which advanced airway device has better placement success and fewer adverse events in out-of-hospital cardiac arrests (OHCAs). This study aimed to evaluate the efficacy of the VBM laryngeal tube (LT) against the laryngeal mask airway (LMA) in OHCAs managed by emergency ambulances in Singapore. METHODS This was a real-world, prospective, cluster-randomised crossover study. All OHCA patients above 13 years of age who were suitable for resuscitation were randomised to receive either LT or LMA. The primary outcome was placement success. Per-protocol analysis was performed, and the association between outcomes and airway device group was compared using multivariate binomial logistic regression analysis. RESULTS Of 965 patients with OHCAs from March 2016 to January 2018, 905 met the inclusion criteria, of whom 502 (55.5%) were randomised to receive LT while 403 (44.5%) were randomised to receive LMA. Only 174 patients in the LT group actually received the device owing to noncompliance. Placement success rate for LT was lower than for LMA (adjusted odds ratio [OR] 0.52, 95% confidence interval [CI] 0.31–0.90). Complications were more likely when using LT (OR 2.82,0 95% CI 1.64–4.86). Adjusted OR for prehospital return of spontaneous circulation (ROSC) was similar in both groups. A modified intention-to-treat analysis showed similar outcomes to the per-protocol analysis between the groups. CONCLUSION LT was associated with poorer placement success and higher complication rates than LMA. The likelihood of prehospital ROSC was similar between the two groups. Familiarity bias and a low compliance rate to LT were the main limitations of this study.
Psychosocial concerns predict longitudinal trajectories of distress in newly diagnosed cancer patients
Authors: Liu J , Lam KFY , Mahendran R
Published: August 2020

INTRODUCTION Unmet psychosocial concerns are associated with emotional distress among cancer patients. This longitudinal study aimed to identify specific psychosocial concern profiles and trajectories of emotional distress, and examine their association among newly diagnosed adult cancer patients across the first year of diagnosis. METHODS Adult patients aged 21–64 years were screened to determine their eligibility for this study. Psychosocial concerns and psychological distress were measured using the Problem List and the Distress Thermometer, respectively (n = 221). Latent transition mixture analysis was used to determine specific psychosocial concern profiles and trajectories of emotional distress, and examine associations with adjustments made for demographic and medical variables. RESULTS Two classes of psychosocial concerns were identified: low (81%) and high (19%) concerns. Two trajectories of distress were identified: low stable (69%) and high stable (31%) trajectories. Patients in the high concerns class were significantly more likely to demonstrate the high stable trajectory of distress. CONCLUSION Our findings highlight the importance of concurrent assessment of multiple psychosocial concerns and screening of emotional distress throughout a cancer patient’s treatment journey. Such assessments can effectively guide interventions to address individual concerns and alleviate emotional distress among newly diagnosed cancer patients.
Changes in the prevalence of comorbidity of mental and physical disorders in Singapore between 2010 and 2016
Authors: Abdin E , Chong SA , Vaingankar JA , Shafie S , Seah D , Chan CT , Ma S , James L , Heng D , Subramaniam M
Published: August 2020

INTRODUCTION Few studies have examined the changes in the prevalence of comorbidity of mental and physical disorders in recent years. The present study sought to examine whether the prevalence of comorbidity of mental and physical disorders in Singapore showed any changes between 2010 and 2016. METHODS We extracted data from two repeated nationally representative cross-sectional surveys conducted among resident adults aged ≥ 18 years in Singapore. Significant changes were tested using pooled multinomial logistic regression analyses. RESULTS The prevalence of comorbid mental and physical disorders increased significantly from 5.8% in 2010 to 6.7% in 2016. Among those with physical disorders, there were significant increases over time in the prevalence of comorbid generalised anxiety disorder (GAD) (0.1% vs. 0.4%) and obsessive-compulsive disorder (OCD) (1.4% vs. 3.9%) in diabetes mellitus, and alcohol dependence in cardiovascular disorders (0.1% vs. 1.3%). Among those with mental disorders, there were significant increases over time in the prevalence of comorbid diabetes mellitus in OCD (4.1% vs. 10.9%), cancer in major depressive disorder (0.4% vs. 2.4%), and cardiovascular disorders in GAD (0.4% vs. 6.7%) and alcohol dependence (0.9% vs. 11.8%). Significant changes in the overall prevalence of comorbid mental and physical disorders were also observed across age group, education and employment status. CONCLUSION The prevalence of comorbid mental and physical disorders increased significantly over time. This finding supports the need for more appropriate clinical management with better integration between mental health and general medical care professionals across all aspects of the healthcare system to treat this comorbidity in Singapore.
On the Prospects for Improved Tropical Cyclone Track Forecasts
Authors: Zhou Feifan , Toth Zoltan
Published: August 2020

The success story of numerical weather prediction is often illustrated with the dramatic decrease of errors in tropical cyclone track forecasts over the past decades. In a recent essay, Landsea and Cangialosi, however, note a diminishing trend in the reduction of perceived positional error (PPE; difference between forecast and observed positions) in National Hurricane Center tropical cyclone (TC) forecasts as they contemplate whether “the approaching limit of predictability for tropical cyclone track prediction is near or has already been reached.” In this study we consider a different interpretation of the PPE data. First, we note that PPE is different from true positional error (TPE; difference between forecast and true positions) as it is influenced by the error in the observed position of TCs. PPE is still customarily used as a proxy for TPE since the latter is not directly measurable. As an alternative, TPE is estimated here with an inverse method, using PPE measurements and a theoretically based assumption about the exponential growth of TPE as a function of lead time. Eighty-nine percent variance in the behavior of 36–120-h lead-time 2001–17 seasonally averaged PPE measurements is explained with an error model using just four parameters. Assuming that the level of investments, and the pace of improvements to the observing, modeling, and data assimilation systems continue unabated, the four-parameter error model indicates that the time limit of predictability at the 181 nautical mile error level (n mi; 1 n mi = 1.85 km), reached at day 5 in 2017, may be extended beyond 6 and 8 days in 10 and 30 years’ time, respectively.
Major Over- and Underestimation of Drought Found in NOAA’s Climate Divisional SPI Dataset
Authors: Spade Daniela , de Beurs Kirsten , Shafer Mark
Published: August 2020

Evaluation of the standardized precipitation index (SPI) dataset published monthly in the National Oceanic and Atmospheric Administration/National Centers for Environmental Information (NOAA/NCEI) climate divisional database revealed that drought frequency is being mischaracterized in climate divisions across the United States. The 3- and 6-month September SPI values were downloaded from the database for all years between 1931 and 2019; the SPI was also calculated for the same time scales and span of years following the SPI method laid out by NOAA/NCEI. Drought frequency is characterized as the total number of years that the SPI fell below −1. SPI values across 1931–90, the calibration period cited by NOAA/NCEI, showed regional patterns in climate divisions that are biased toward or away from drought, according to the average values of the SPI. For both time scales examined, the majority of the climate divisions in the central, Midwest, and northeastern United States showed negative averages, indicating bias toward drought, whereas climate divisions in the western United States, the northern Midwest, and parts of the Southeast and Texas had positive averages, indicating bias away from drought. The standard deviation of the SPI also differed from the expected value of 1. These regional patterns in the NCEI’s SPI values are the result of a different (sliding) calibration period, 1895–2019, instead of the cited standardized period of 1931–90. The authors recommend that the NCEI modify its SPI computational procedure to reflect the best practices identified in the benchmark papers, namely, a fixed baseline period.
The Influence of Terrain on the Convective Environment and Associated Convective Morphology from an Idealized Modeling Perspective
Authors: Mulholland Jake P. , Nesbitt Stephen W. , Trapp Robert J. , Peters John M.
Published: August 2020

Orographic deep convection (DC) initiation and rapid evolution from supercells to mesoscale convective systems (MCSs) are common near the Sierras de Córdoba, Argentina, which was the focal point of the Remote Sensing of Electrification, Lightning, and Mesoscale/Microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaign. This study used an idealized numerical model with elongated north–south terrain similar to that of the Sierras de Córdoba to address how variations in terrain height affected the environment and convective morphology. Simulations used a thermodynamic profile from a RELAMPAGO event that featured both supercell and MCS storm modes. Results revealed that DC initiated earlier in simulations with higher terrain, owing both to stronger upslope flows and standing mountain waves. All simulations resulted in supercell formation, with higher-terrain supercells initiating closer to the terrain peak and moving slower off the terrain. Higher-terrain simulations displayed increases in both low-level and deep-layer wind shear along the eastern slopes of the terrain that were related to the enhanced upslope flows, supporting stronger and wider supercell updrafts/downdrafts and a wider swath of heavy rainfall. Deeper and stronger cold pools from these wider and stronger higher-terrain supercells led to surging outflow that reduced convective available potential energy accessible to deep convective updrafts, resulting in quicker supercell demise off the terrain. Lower-terrain supercells moved quickly off the terrain, merged with weaker convective cells, and resulted in a quasi-organized MCS. These results demonstrate that terrain-induced flow modification may lead to substantial local variations in convective morphology.
Impact of Convectively Generated Low-Frequency Gravity Waves on Evolution of Mesoscale Convective Systems
Authors: Adams-Selin Rebecca D.
Published: August 2020

Idealized numerical simulations of mesoscale convective systems (MCSs) over a range of instabilities and shears were conducted to examine low-frequency gravity waves generated during initial and mature stages of convection. In all simulations, at initial updraft development a first-order wave was generated by heating extending through the depth of the troposphere. Additional first-order wave modes were generated each time the convective updraft reintensified. Each of these waves stabilized the environment in advance of the system. As precipitation descended below cloud base, and as a stratiform precipitation region developed, second-order wave modes were generated by cooling extending from the midlevels to the surface. These waves destabilized the environment ahead of the system but weakened the 0–5 km shear. Third-order wave modes could be generated by midlevel cooling caused by rear inflow intensification; these wave modes cooled the midlevels destabilizing the environment. The developing stage of each MCS was characterized by a cyclical process: developing updraft, generation of n = 1 wave, increase in precipitation, generation of n = 2 wave, and subsequent environmental destabilization reinvigorating the updraft. After rearward expansion of the stratiform region, the MCSs entered their mature stage and the method of updraft reinvigoration shifted to absorbing discrete convective cells produced in advance of each system. Higher-order wave modes destabilized the environment, making it more favorable to development of these cells and maintenance of the MCS. As initial simulation shear or instability increased, the transition from cyclical wave/updraft development to discrete cell/updraft development occurred more quickly.
Direct and Indirect Effects of Surface Fluxes on Moist Baroclinic Development in an Idealized Framework
Authors: Haualand Kristine F. , Spengler Thomas
Published: August 2020

The convoluted role of surface sensible and latent heat fluxes on moist baroclinic development demands a better understanding to disentangle their local and remote effects. Including diabatic effects in the Eady model, the direct effects of surface fluxes on the diabatic generation of eddy available potential energy as well as their indirect effects through modifications of the circulation and latent heating are investigated. It is shown that surface sensible heat fluxes have a minor impact, irrespective of their position and parameterization, while latent heating in the region equivalent to the warm conveyor belt is the dominant diabatic source for development. Downward surface sensible heat fluxes in proximity of the warm conveyor belt results in structural modifications that increase the conversion from basic-state available potential energy to eddy available potential energy, while concomitantly weakening the ascent and hence latent heating. The detrimental effects are easily compensated through provision of additional moisture into the warm conveyor belt. Upward surface heat fluxes in the cold sector, on the other hand, are detrimental to growth. When downward (upward) surface sensible heat fluxes are located below the equivalent of the warm conveyor belt, the diabatically induced PV anomaly at the bottom of the latent heating layer becomes dominant (less dominant). Shifting the downward surface sensible heat fluxes away from the warm conveyor belt results in substantial changes in the growth rate, latent heat release, low-level structure, and energetics, where the effect of surface sensible heat fluxes might even be beneficial.
New Insights into Wind Shear Effects on Entrainment in Convective Boundary Layers Using Conditional Analysis
Authors: Fodor Katherine , Mellado Juan Pedro
Published: August 2020

Conventional analysis has shown that strong wind shear enhances the entrainment buoyancy flux in the convective boundary layer. By conditioning the entrainment zone into regions of turbulent (i.e., strongly vortical) and nonturbulent (i.e., weakly vortical) flow, some unexpected aspects of this process are revealed. It is found that turbulent regions contribute the most to the entrainment buoyancy flux, but that as wind shear increases, the magnitude of the buoyancy flux in turbulent regions remains approximately constant, or even decreases, despite substantially stronger buoyancy fluctuations. The reason is that the correlation between buoyancy and vertical velocity fluctuations decreases with increasing wind shear, to the extent that it compensates the stronger buoyancy fluctuations. In free convection, this correlation is high because the vertical velocity is mainly determined by the buoyancy force acting in the same direction. Under strong shear conditions, buoyancy is no longer the only external source of vertical velocity fluctuations and their correlation consequently decreases. Hence, shear enhancement of the buoyancy flux in the entrainment zone is primarily due to an increase of the turbulent area fraction, rather than a change of flux inside the turbulent regions.
Consistent Impacts of Surface Enthalpy and Drag Coefficient Uncertainty between an Analytical Model and Simulated Tropical Cyclone Maximum Intensity and Storm Structure
Authors: Nystrom Robert G. , Rotunno Richard , Davis Chris A. , Zhang Fuqing
Published: August 2020

Several previous studies have demonstrated the significant sensitivity of simulated tropical cyclone structure and intensity to variations in surface-exchange coefficients for enthalpy (Ck) and momentum (Cd), respectively. In this study we investigate the consistency of the estimated peak intensity, intensification rate, and steady-state structure between an analytical model and idealized axisymmetric numerical simulations for both constant Ck and Cd values and various wind speed–dependent representations of Ck and Cd. The present analysis with constant Ck and Cd values demonstrates that the maximum wind speed is similar for identical Ck/Cd values less than 1, regardless of whether changes were made to Ck or Cd. However, for a given Ck/Cd greater than 1, the simulated and theoretical maximum wind speed are both greater if Cd is decreased compared to Ck increased. This behavior results because of a smaller enthalpy disequilibrium at the radius of maximum winds for larger Ck. Additionally, the intensification rate is shown to increase with Ck and Cd and the steady-state normalized wind speed beyond the radius of maximum winds is shown to increase with increasing Cd. Experiments with wind speed–dependent Ck and Cd were found to be generally consistent, in terms of the intensification rate and the simulated and analytical-model-estimated maximum wind speed, with the experiments with constant Ck and Cd.
The Role of WISHE in the Rapid Intensification of Tropical Cyclones
Authors: Cheng Chieh-Jen , Wu Chun-Chieh
Published: August 2020

This study examines the role of surface heat fluxes, particularly in relation to the wind-induced surface heat exchange (WISHE) mechanism, in the rapid intensification (RI) of tropical cyclones (TCs). Sensitivity experiments with capped surface fluxes and thus reduced WISHE exhibit delayed RI and weaker peak intensity, while WISHE could affect the evolutions of TCs both before and after the onset of RI. Before RI, more WISHE leads to faster increase of equivalent potential temperature in the lower levels, resulting in more active and stronger convection. In addition, TCs in experiments with more WISHE reach a certain strength earlier, before the onset of RI. During the RI period, more surface heat fluxes could provide convective instability in the lower levels, and cause a consequent development in the convective activity. More efficient intensification in a TC is found with higher surface heat fluxes and larger inertial stability, leading to a stronger peak intensity, more significant and deeper warm core in TC center, and the axisymmetrization of convection in the higher levels. In both stages, different levels of WISHE alter the thermodynamic environment and convective-scale processes. In all, this study supports the crucial role of WISHE in affecting TC intensification rate for TCs with RI.
Numerical Simulations of Orographic Convection across Multiple Gray Zones
Authors: Kirshbaum Daniel J.
Published: August 2020

Idealized simulations are used to determine the sensitivity of moist orographic convection to horizontal grid spacing Δh. In simulated mechanically (MECH) and thermally (THERM) forced convection over an isolated ridge, Δh is varied systematically over both the deep-convection (Δh ~ 10–1 km) and turbulence (Δh ~ 1 km–100 m) gray zones. To aid physical interpretation, a new parcel-based bulk entrainment/detrainment diagnosis for horizontally heterogeneous flows is developed. Within the deep-convection gray zone, the Δh sensitivity is dominated by differences in parameterized versus explicit convection; the former initiates convection too far upstream of the ridge (MECH) and too early in the diurnal heating cycle (THERM). These errors stem in part from a large underprediction of parameterized entrainment and detrainment. Within the turbulence gray zone, sensitivities to Δh arise from the representation of both subcloud- and cloud-layer turbulence. As Δh is decreased, MECH exhibits stronger cloud-layer entrainment to enhance the convective mass flux Mco, while THERM exhibits stronger detrainment to suppress Mco and delay convection initiation. The latter is reinforced by increased subcloud turbulence at smaller Δh, which leads to drying and diffusion of the central updraft responsible for initiating moist convection. Numerical convergence to a robust solution occurs only in THERM, which develops a fully turbulent flow with a resolved inertial subrange (for Δh ≤ 250 m). In MECH, by contrast, turbulent transition occurs within the orographic cloud, the details of which depend on both physical location and Δh.
Drop Size Distribution Broadening Mechanisms in a Bin Microphysics Eulerian Model
Authors: Pardo Lianet Hernández , Morrison Hugh , Machado Luiz A. T. , Harrington Jerry Y. , Lebo Zachary J.
Published: August 2020

In this study, processes that broaden drop size distributions (DSDs) in Eulerian models with two-moment bin microphysics are analyzed. Numerous tests are performed to isolate the effects of different physical mechanisms that broaden DSDs in two- and three-dimensional Weather Research and Forecasting Model simulations of an idealized ice-free cumulus cloud. Sensitivity of these effects to modifying horizontal and vertical model grid spacings is also examined. As expected, collision–coalescence is a key process broadening the modeled DSDs. In-cloud droplet activation also contributes substantially to DSD broadening, whereas evaporation has only a minor effect and sedimentation has little effect. Cloud dilution (mixing of cloud-free and cloudy air) also broadens the DSDs considerably, whether or not it is accompanied by evaporation. This mechanism involves the reduction of droplet concentration from dilution along the cloud’s lateral edges, leading to locally high supersaturation and enhanced drop growth when this air is subsequently lifted in the updraft. DSD broadening ensues when the DSDs are mixed with those from the cloud core. Decreasing the horizontal and vertical model grid spacings from 100 to 30 m has limited impact on the DSDs. However, when these physical broadening mechanisms (in-cloud activation, collision–coalescence, dilution, etc.) are turned off, there is a reduction of DSD width by up to ~20%–50% when the vertical grid spacing is decreased from 100 to 30 m, consistent with effects of artificial broadening from vertical numerical diffusion. Nonetheless, this artificial numerical broadening appears to be relatively unimportant overall for DSD broadening when physically based broadening mechanisms in the model are included for this cumulus case.
A Formula for the Maximum Vertical Velocity in Supercell Updrafts
Authors: Peters John M. , Morrison Hugh , Nowotarski Christopher J. , Mulholland Jake P. , Thompson Richard L.
Published: August 2020

In supercell environments, previous authors have shown strong connections between the vertical wind shear magnitude, updraft width, and entrainment. Based on these results, it is hypothesized that the influences of entrainment-driven dilution on buoyancy and maximum updraft vertical velocity w in supercell environments are a predictable function of the vertical wind shear profile. It is also hypothesized that the influences of pressure perturbation forces on maximum updraft w are small because of a nearly complete offset between upward dynamic pressure forces and downward buoyant pressure forces. To address these hypotheses, we derive a formula for the maximum updraft w that incorporates the effects of entrainment-driven dilution on buoyancy but neglects pressure gradient forces. Solutions to this formula are compared with output from previous numerical simulations. This formula substantially improves predictions of maximum updraft w over past CAPE-derived formulas for maximum updraft w, which supports the first hypothesis. Furthermore, integrated vertical accelerations along trajectories show substantial offsets between dynamic and buoyant pressure forces, supporting the second hypothesis. It is argued that the new formula should be used in addition to CAPE-derived measures for w in forecast and research applications when accurate diagnosis of updraft speed is required.
Scale and Rossby Number Dependence of Observed Wind Responses to Ocean-Mesoscale Sea Surface Temperatures
Authors: Schneider Niklas
Published: August 2020

The horizontal scale dependences of in-phase and lagged imprints of ocean-mesoscale sea surface temperatures on surface winds are investigated using daily AMSR-E radiometer and QuikSCAT scatterometer observations in the Southern Ocean. Spectral transfer functions separate underlying processes dependent on large-scale winds, horizontal wavenumbers, and corresponding Rossby numbers. For Rossby numbers smaller than 1, winds reflect modulations of the Ekman layer by sea surface temperature–induced changes of hydrostatic pressure. Rossby numbers large compared to 1 suggest a balance of advection and modulations of vertical mixing. Impulse response functions reveal Southern Hemisphere, Doppler-shifted, near-inertial lee waves excited by warm ocean-mesoscale sea surface temperatures. On the right (left) flank of the downwind wake of warm air and low atmospheric pressure, winds are enhanced (diminished) due to constructive (destructive) interference of inertial turning, pressure gradient forces, and vertical mixing. Wind convergence over the warm wake is stronger compared to the upwind divergence. Time averaging smooths the response, and degrades the lee wave.
A Comparison of the Vorticity Dynamics Governing the Oceanic Bomb Cyclone of 4–5 January 1989 and the Super Derecho of 8 May 2009
Authors: Galarneau Jr. Thomas J. , Weisman Morris L.
Published: August 2020

Convection-allowing simulations of two warm seclusion cyclones are used to elucidate the vorticity dynamics that contribute to intensification of these systems. The rapidly intensifying oceanic “bomb” cyclone on 4–5 January 1989 and the super derecho on 8 May 2009 are the subject of this study. While these systems occupy different spatial scales, they both acquire characteristics of a warm seclusion cyclone. The aim of this study is to compare the basic structure and determine the dynamics driving increases in system-scale vertical vorticity during the intensification of these systems. Results from a vorticity budget show that system-scale stretching and the lateral transport of vertical vorticity to the cyclone center contribute to increases of system-scale low-level vertical vorticity during the intensification of the oceanic cyclone. The intercomparison of the oceanic cyclone and the super derecho shows that the relative contributions to increases in system-scale vertical vorticity by stretching and tilting as a function of height differ among the two cases. However, the lateral transport of vertical vorticity to the cyclone center is a key contributor to increases in low-level system-scale vertical vorticity for both cases. We hypothesize that this process may be common among a wide array of intense cyclonic systems across scales ranging from warm seclusion extratropical cyclones to some mesoscale convective systems.
The Climatology of Lower Tropospheric Temperature Inversions in China from Radiosonde Measurements: Roles of Black Carbon, Local Meteorology, and Large-Scale Subsidence
Authors: Guo Jianping , Chen Xinyan , Su Tianning , Liu Lin , Zheng Youtong , Chen Dandan , Li Jian , Xu Hui , Lv Yanmin , He Bingfang , Li Yuan , Hu Xiao-Ming , Ding Aijun , Zhai Panmao
Published: August 2020

The variability of the lower tropospheric temperature inversion (TI) across China remains poorly understood. Using seven years’ worth of high-resolution radiosonde measurements at 120 sites, we compile the climatology of lower tropospheric TI in terms of frequency, intensity, and depth during the period from 2011 to 2017. The TI generally exhibits strong seasonal and geographic dependencies. Particularly, the TI frequency is found to be high in winter and low in summer, likely due to the strong aerosol radiative effect in winter. The frequency of the surface-based inversion (SBI) exhibits a “west low, east high” pattern at 0800 Beijing time (BJT), which then switches to “west high, east low” at 2000 BJT. Both the summertime SBI and elevated inversion (EI) reach a peak at 0800 BJT and a trough at 1400 BJT. Interestingly, the maximum wintertime EI frequency occurs over Southeast China (SEC) rather than over the North China Plain (NCP), likely attributable to the combination of the heating effect of black carbon (BC) originating from the NCP, along with the strong subsidence and trade inversion in SEC. Correlation analyses between local meteorology and TI indicate that larger lower tropospheric stability (LTS) favors more frequent and stronger TIs, whereas the stronger EI under smaller LTS conditions (unstable atmosphere) is more associated with subsidence rather than BC. Overall, the spatial pattern of the lower tropospheric TI and its variability in China are mainly controlled by three factors: local meteorology, large-scale subsidence, and BC-induced heating. These findings help shed some light on the magnitude, spatial distribution, and underlying mechanisms of the lower tropospheric TI variation in China.
Contributions of Different Combinations of the IPO and AMO to the Concurrent Variations of Summer East Asian Jets
Authors: Xiao Xiucheng , Huang Danqing , Yang Ben , Zhu Jian , Yan Peiwen , Zhang Yaocun
Published: August 2020

Huang et al. recently reported that opposite phases of the interdecadal Pacific oscillation (IPO) and the Atlantic multidecadal oscillation (AMO) can affect the shift of the East Asian polar front jet (EAPJ) and the East Asian subtropical jet (EASJ) in the boreal winter. To give a full image of the relationship among the IPO, AMO, and concurrent variation of jets throughout the whole year, this study investigates the changes in summer jets response to the combinations of the IPO and AMO, and mostly focuses on the quantitative analysis in the role of the IPO and AMO. Both of the diagnostic analysis and atmospheric model simulations confirm that combinations of the negative phase of the IPO (“−IPO”) and the positive phase of the AMO (“+AMO”) can significantly enhance the EAPJ and reduce the EASJ in the summer, via the meridional temperature gradient and the Eady growth rate, and vice versa in the “+IPO −AMO” combination. The reanalysis data show that this relationship is particularly evident between the periods of 1999–2014 and 1979–98. Based on the simulations, the multilinear regression has indicated that −IPO plays a more important role than +AMO, particularly for the reduced EASJ. We have further revealed two pathways of the stationary Rossby wave activity anomaly, eastward from the North Atlantic to East Asia along 60°N and westward from the North Pacific to East Asia along 40°N. The two activities are associated with anomalous anticyclone along the active regions between EAPJ and EASJ, and therefore affect the jet variations.
Analysis of Record-High Temperature over Southeast Coastal China in Winter 2018/19: The Combined Effect of Mid- to High-Latitude Circulation Systems and SST Forcing over the North Atlantic and Tropical Western Pacific
Authors: Jian Yuntao , Lin Xiaoxia , Zhou Wen , Jian Maoqiu , Leung Marco Y. T. , Cheung Paxson K. Y.
Published: August 2020

In winter 2018/19, southeastern coastal China experienced extreme warm temperatures that were due to a weak East Asian winter monsoon. On the basis of observations from 10 meteorological stations and reanalysis data, the large-scale circulation patterns associated with this extreme warm winter and the possible driving mechanism of its related sea surface temperature (SST) anomalies are investigated in this study. During this winter, many places in this region reached their highest winter mean temperature record and had more extreme warm days and fewer extreme cold days relative to climatology. According to the circulation patterns during winter 2018/19, several large-scale circulation conditions associated mainly with the weak East Asian winter monsoon are identified: the eastward shift of the Siberian high and a shallower East Asian trough, which is related to the low blocking frequency over the Aleutian region, are both unfavorable for cold-air intrusion southward. Meanwhile, strong low-level southerly wind anomalies over southeastern China are related mainly to the 2018/19 El Niño event. Furthermore, the possible role of SST anomalies over the North Atlantic and tropical western Pacific Oceans is examined by using an atmospheric general circulation model, suggesting that both the “tripole pattern” of North Atlantic SST and tropical western Pacific SST anomalies in winter 2018/19 played a role in influencing the East Asian trough. The combined effect of all of these factors seems to be responsible for this extreme warm winter over southeastern coastal China.
Improved Detection of Interannual Cloud Variability over the Southern Hemisphere Using Legacy Satellites
Authors: Liu Shay , Staten Paul W. , Kahn Brian H.
Published: August 2020

Shifts in deep tropical convection and midlatitude jet streams both manifest themselves in high cloud anomalies. Such anomalies may play a significant role in local to global climate processes. This work investigates how high cloud properties covary with two primary interannual modes of variability in the Southern Hemisphere (SH): El Niño–Southern Oscillation (ENSO) and the southern annular mode (SAM). In contrast to several recent studies that utilize the latest remote sensing datasets (e.g., CloudSat), we employ a novel combination of imager and sounder data from legacy satellite instruments. Using these legacy data, we confirm the poleward shift of high cloud fields in the SH midlatitudes with SAM seen in other recent studies and characterize the opposing impacts of SAM and ENSO on the South Pacific convergence zone and Southern Hemisphere storm tracks. Furthermore, we demonstrate that the standard deviation of brightness temperature data from the window channel acts as a surrogate for high cloud fraction in the tropics and midlatitudes. Our results reconcile apparent differences in recent studies and suggest that brightness temperature standard deviations are climate relevant, in addition to being largely insensitive to instrument calibration.
Is the North Pacific Victoria Mode a Predictor of Winter Rainfall over South China?
Authors: Zou Qian , Ding Ruiqiang , Li Jianping , Tseng Yu-heng , Hou Zhaolu , Wen Tao , Ji Kai
Published: August 2020

This study investigates the connection between the North Pacific Victoria mode (VM) during the boreal spring [February–April (FMA)] and the following boreal winter [January–March (JFM)] rainfall over South China (SC). The VM is defined as the second empirical orthogonal function mode (EOF2) of sea surface temperature (SST) anomalies (SSTAs) in the North Pacific poleward of 20°N. It is found that the boreal spring VM has a significant positive correlation with the following winter rainfall over SC. Analyses indicate that a strong positive VM during spring can induce El Niño during the following winter via an air–sea interaction, resulting in the generation of an anomalous anticyclone over the western North Pacific (WNPAC). The anomalous southwesterlies along the southeast coast of East Asia associated with the WNPAC favor an abundant supply of water vapor and anomalous ascending motion over SC. As a result, winter rainfall over SC increases. A linear regression model based on the VM shows that the VM can act as an effective predictor of winter rainfall over SC about 1 year in advance. It also has a higher prediction skill than ENSO in predicting winter rainfall over SC.
Response of the Asian Summer Monsoon Precipitation to Global Warming in a High-Resolution Global Nonhydrostatic Model
Authors: Takahashi Hiroshi G. , Kamizawa Nozomi , Nasuno Tomoe , Yamada Youhei , Kodama and Chihiro , Sugimoto Shiori , Satoh Masaki
Published: August 2020

This study examined the responses of Asian monsoon precipitation to global warming on the regional scale, focusing on monsoon westerlies and monsoon trough. This is because the Asian monsoon precipitation is closely associated with tropical disturbances. To reproduce convective precipitation and tropical disturbances, this study used outputs of a high-resolution climate simulation. Two sets of approximately 30-yr simulations under present-day (control) and warmer climate conditions (global warming) were conducted by the 14-km Nonhydrostatic Icosahedral Atmospheric Model (NICAM) with explicitly calculated convection. For understanding the spatial pattern of future precipitation changes, a further set of a 5-yr simulation [sea surface temperature (SST) + 4 K] was also conducted. Overall, the Asian summer monsoon was well simulated by the model. Precipitation increased as a result of global warming along the monsoon trough, which was zonally elongated across northern India, the Indochina Peninsula, and the western North Pacific Ocean. This increased precipitation was likely due to an increase in precipitable water. The spatial pattern of the increased precipitation was associated with enhanced cyclonic circulations over a large area along the monsoon trough, although it was difficult to determine whether the large-scale monsoon westerly was enhanced. This enhancement can be explained by future changes in tropical disturbance activity, including weak tropical cyclones. However, over part of South Asia, circulation changes may not contribute to the increased precipitation, suggesting regional characteristics. The regional increase in precipitation along the monsoon trough was mostly explained by the uniform increase in SST, whereas SST spatial patterns are important over some regions.
Origins of East Asian Summer Monsoon Seasonality
Authors: Chiang J. C. H. , Kong W. , Wu C. H. , Battisti D. S.
Published: August 2020

The East Asian summer monsoon is unique among summer monsoon systems in its complex seasonality, exhibiting distinct intraseasonal stages. Previous studies have alluded to the downstream influence of the westerlies flowing around the Tibetan Plateau as key to its existence. We explore this hypothesis using an atmospheric general circulation model that simulates the intraseasonal stages with fidelity. Without a Tibetan Plateau, East Asia exhibits only one primary convective stage typical of other monsoons. As the plateau is introduced, the distinct rainfall stages—spring, pre-mei-yu, mei-yu, and midsummer—emerge, and rainfall becomes more intense overall. This emergence coincides with a pronounced modulation of the westerlies around the plateau and extratropical northerlies penetrating northeastern China. The northerlies meridionally constrain the moist southerly flow originating from the tropics, leading to a band of lower-tropospheric convergence and humidity front that produces the rainband. The northward migration of the westerlies away from the northern edge of the plateau leads to a weakening of the extratropical northerlies, which, coupled with stronger monsoonal southerlies, leads to the northward migration of the rainband. When the peak westerlies migrate north of the plateau during the midsummer stage, the extratropical northerlies disappear, leaving only the monsoon low-level circulation that penetrates northeastern China; the rainband disappears, leaving isolated convective rainfall over northeastern China. In short, East Asian rainfall seasonality results from the interaction of two seasonally evolving circulations—the monsoonal southerlies that strengthen and extend northward, and the midlatitude northerlies that weaken and eventually disappear—as summer progresses.
Comparing Methods to Constrain Future European Climate Projections Using a Consistent Framework
Authors: Brunner Lukas , McSweeney Carol , Ballinger Andrew P. , Befort Daniel J. , Benassi Marianna , Booth Ben , Coppola Erika , de Vries Hylke , Harris Glen , Hegerl Gabriele C. , Knutti Reto , Lenderink Geert , Lowe Jason , Nogherotto Rita , O’Reilly Chris , Qasmi Saïd , Ribes Aurélien , Stocchi Paolo , Undorf Sabine
Published: August 2020

Political decisions, adaptation planning, and impact assessments need reliable estimates of future climate change and related uncertainties. To provide these estimates, different approaches to constrain, filter, or weight climate model projections into probabilistic distributions have been proposed. However, an assessment of multiple such methods to, for example, expose cases of agreement or disagreement, is often hindered by a lack of coordination, with methods focusing on a variety of variables, time periods, regions, or model pools. Here, a consistent framework is developed to allow a quantitative comparison of eight different methods; focus is given to summer temperature and precipitation change in three spatial regimes in Europe in 2041–60 relative to 1995–2014. The analysis draws on projections from several large ensembles, the CMIP5 multimodel ensemble, and perturbed physics ensembles, all using the high-emission scenario RCP8.5. The methods’ key features are summarized, assumptions are discussed, and resulting constrained distributions are presented. Method agreement is found to be dependent on the investigated region but is generally higher for median changes than for the uncertainty ranges. This study, therefore, highlights the importance of providing clear context about how different methods affect the assessed uncertainty—in particular, the upper and lower percentiles that are of interest to risk-averse stakeholders. The comparison also exposes cases in which diverse lines of evidence lead to diverging constraints; additional work is needed to understand how the underlying differences between methods lead to such disagreements and to provide clear guidance to users.