High-impact weather events can occur downstream from recurving western North Pacific (WNP) tropical cyclones (TCs) that undergo extratropical transition and interact strongly with the midlatitude flow. These events are the result of jet streak intensification and downstream wave amplification triggered by a prolonged period of strong negative potential vorticity (PV) advection by the divergent component of the wind in the TC outflow region, here called Rossby wave (RW) forcing. A 46-yr global climatology of all TC-related RW forcing episodes during 1979-2024 is obtained to test the hypothesis that RW forcing events can occur outside of the recurving WNP TC context. Using global TC data from the International Best Track Archive for Climate Stewardship (IBTrACS) database, it is first demonstrated that strong RW forcing events associated with recurving TCs are mostly confined to the WNP basin. Downstream response is assessed by determining composite time series of the downstream meridional index, 250-hPa wind speed, and a proxy for midlatitude cyclones. Removing the requirement for TC recurvature resulted in a ;72% increase in cases but with no significant change in downstream response, suggesting that TC recurvature is not a prerequisite for excitation or amplification of Rossby waves. A similar but smaller downstream response occurred in other TC basins. Spatial composites for recurving TCs revealed that the downstream response reflected the direct impact of TCs migrating into the compositing domain rather than remote downstream Rossby wave amplification triggered by the RW forcing. Spatial composites for nonrecurving TCs having little eastward progression revealed an amplifying standing wave pattern downstream from the longitude of the RW forcing.

BACKGROUND:In recent years, nonoperative treatment of pediatric type I open both bone forearm fractures (OBBFFs) with bedside irrigation, antibiotics, closed reduction, and casting has yielded low infection rates. However, risk factors for failure of type I OBBFF closed reduction have not been well described. Our purpose was to describe management of patients with type I OBBFFs at our institution and determine what factors are associated with failure of closed reduction in this population.METHODS:This was a review of patients between 5 and 15 years of age who received initial nonoperative management for type I OBBFFs at one institution between 2015 and 2021. Primary outcome was success or failure of nonoperative management (defined as progression to surgical management). Secondary outcomes included infections, compartment syndromes, and neuropraxias. Other variables of interest were demographic information, prereduction and postreduction translation and angulation of the radius and ulna, cast index, and antibiotic administration.RESULTS:Sixty-one patients (67.7% male) with 62 type I OBBFFs were included in this study. Following initial nonoperative management, 55 injuries (88.7%) were successfully treated in casts, while the remaining 7 (11.3%) required surgical intervention following loss of acceptable reduction in cast. Median cast index (0.84, IQR 0.8 to 0.9 vs. 0.75, IQR 0.7-0.8, P =0.020) and postreduction radius translation on anteroposterior films (32.0%, IQR 17.0% to 40.0% vs. 5.0%, IQR 0.0% to 26.0%, P =0.020) were higher among those who failed nonoperative management. Multivariable logistic regression models identified increased odds of failure for every SD (0.7) increase in cast index (OR 3.78, P =0.023, 95% CI: 1.4-14.3) and 25% increase in postreduction radius translation on anteroposterior films (OR 7.39, P =0.044, 95% CI 1.2-70.4). No infections or compartment syndromes and 2 transient ulnar neuropraxias occurred.CONCLUSIONS:Closed reduction of type I OBBFFs was successful in 88.7% of cases. There were no infections after nonoperative management. Increases in cast index of 0.7 and postreduction radius translation on anteroposterior radiographs of 25% were associated with increased likelihood of failure, thus requiring surgery; age was not.LEVEL OF EVIDENCE:Level IV-retrospective comparative study.

The deadly shift of the Yarnell Hill, Arizona wildfire was associated with an environment exhibiting gusty wind patterns in response to organized convectively driven circulations. The observed synoptic (>2500 km) through meso-β (approximately 100 km) scale precursor environment that organized a mid-upper tropospheric cross-mountain mesoscale jet streak circulation and upslope thermally direct flow was examined. Numerical simulations and observations indicated that both circulations played a key role in focusing the upper-level divergence, ascent, downdraft potential, vertical wind shear favoring mobile convective gust fronts, and a microburst. This sequence was initiated at the synoptic scale by a cyclonic Rossby Wave Break (RWB) 72 h prior, followed by an anticyclonic RWB. These RWBs combined to produce a mid-continent baroclinic trough with two short waves ushering in cooler air with the amplifying polar jet. Cool air advection with the second trough and surface heating across the Intermountain West (IW) combined to increase the mesoscale pressure gradient, forcing a mid-upper tropospheric subsynoptic jet around the periphery of the upstream ridge over Southern Utah and Northern New Mexico. Convection was triggered by an unbalanced secondary jetlet circulation within the subsynoptic jet in association with a low-level upslope flow accompanying a mountain plains solenoidal circulation above the Mogollon Rim (MR) and downstream mountains.

Background: Acute posterior sternoclavicular dislocations (APSCD) are rare injuries that historically have prompted concern for injury to the great vessels and other mediastinal structures from initial trauma or subsequent treatment, resulting in the recommendation that a thoracic or vascular surgeon be present or available during operative treatment. The objectives of the study were to characterize the demographic, clinical, and radiographic characteristics of a large series of APSCDs in skeletally immature patients and to describe the rate and nature of any vascular or mediastinal complications that occurred during treatment. Methods: Following Institutional Review Board approval, records of consecutive patients under 25 years of age treated for APSCD were collected from each of 6 participating centers. Only acute injuries (sustained fewer than 10 days before presentation) were included. Patient demographics, injury mechanism, associated mediastinal injuries, and need for thoracic/vascular surgery were recorded. Mediastinal structures injured or compressed by mass effect were specifically characterized by review of preoperative computed tomography imaging. Results: Review identified 125 patients with a mean age of 14.7 years; 88% were male. APSCD most commonly resulted from a sporting injury (74%) followed by falls from standing height (10%) and high-energy motor vehicle trauma (10%). The most common finding on cross-sectional imaging was compression without laceration of the ipsilateral brachiocephalic vein (50%). Eleven patients had successful closed reduction, and 114 (90%) had open reduction and internal fixation, with 25 failed or unstable closed reductions preceding open treatment. There were no vascular or mediastinal injuries during reduction or fixation that required intervention. Conclusions: In this multicenter series of 125 APSCDs no injuries to the great vessels/mediastinal structures requiring intervention were identified. Although more than half of patients had evidence of extrinsic vascular compression at the time of injury, careful open reduction of acute injuries can be safely performed. Although vascular injuries following APSCD seem to be quite rare, vascular complications can be catastrophic. Treating providers should consider these data and their own institutional resources to maximize patient safety during the treatment of APSCD. Level of Evidence: Level III—therapeutic case control study.

Background:To examine the current trends in trauma call coverage of pediatric orthopaedic surgeons in North America and to identify predictors of surgeon on-call satisfaction. Methods:In 2015, ∼1200 active members of the Pediatric Orthopaedic Society of North America (POSNA) were surveyed regarding emergency room on-call practices. In total, 410 members completed the survey with a response rate of 35%. Information collected included call frequency, practice setting and satisfaction with call. This information was analyzed and compared with the 2006 and 2010 trauma call surveys of Pediatric Orthopaedic Society of North America membership using 2 sample difference in proportion, &khgr;2 tests for trend and the Fisher exact tests. Logistic regression analyses were used to identify predictors of call satisfaction among pediatric orthopaedic surgeons. Results:In total, 47% of pediatric orthopaedic surgeons had access to a designated trauma operating room in 2015, up from 39% in 2010 and 24% in 2006. In total, 43% of pediatric orthopaedic surgeons currently receive a stipend for taking call, up from 35% in 2010 and 28% in 2006. Although 83% of pediatric orthopaedic surgeons believe that trauma call is an integral part of their practice, only 53% are satisfied with their call experience. Controlling for covariates, believing that call is integral to one’s practice doubles odds of call satisfaction. Having resident or fellow support and being financially compensated for orthopaedic trauma call also increases one’s odds of satisfaction. The odds of being satisfied with call decrease by 7% for each year of increase in age of the surgeon. Conclusions:Access to a designated trauma operating room and financial compensation for call coverage have steadily increased over the past decade. A sizable majority of respondents continue to believe that trauma care is an integral part of being a pediatric orthopedist. Despite this, 47% of respondents remain dissatisfied with their trauma call arrangements. The age and attitude of the individual surgeon and extent of hospital support predict satisfaction of surgeons providing trauma coverage. Level of Evidence:Level V—economic and decision analysis.

The top 100 basin-scale 1-day precipitation, multiday precipitation, and 1-day streamflow events from 1950 to 2012 are examined for the Ashokan reservoir, a key water source for New York City. Through a cyclone association algorithm, extratropical cyclones (ETCs) are found to be associated with the majority of the top 100 precipitation and streamflow events. Tropical cyclones (TCs) generate the second-most top 100 one-day and multiday precipitation events, with more than two-thirds of these TCs having undergone extratropical transition. Furthermore, TCs that pass over the region are approximately 7 and 4 times more likely to generate a top 100 one-day precipitation and one-day streamflow event, respectively, than ETCs. Lagrangian cyclone track analysis shows cool season ETCs take a more meridional path compared to warm season ETCs. A composite analysis shows that for the top 100 one-day precipitation events, ETCs have relatively less moisture but stronger upper-level support than TCs. Due in part to TCs, heavy precipitation events occur more often in the warm season, whereas high streamflow events occur mainly in the cool season. Despite this difference, approximately 43% of the top 100 events, which represent many of the very strongest events, overlap for all three metrics. While high temperature and specific humidity anomalies accompany all top 100 events, the magnitude of the anomalies is greatest for isolated streamflow events. This analysis provides a reference to forecasters and water managers regarding the relative and synoptic-scale behavior of different storm types for isolated and concurrent precipitation and streamflow events.

The aim of this study was to determine whether persistent idiopathic toe walking leads to compensatory skeletal changes in the pediatric foot and ankle. Foot radiographs of children diagnosed with idiopathic toe walking and sex-matched and age-matched controls were retrospectively reviewed. Five blinded providers assessed the foot radiographs for skeletal changes to the ankle. The relationship between each measure and toe-walking status was examined. Providers observed radiographic evidence of skeletal changes of the talus in idiopathic toe walkers compared with controls, suggesting that persistent toe walking impacts the skeletal development of the talus.LEVEL OF EVIDENCE:prognostic level III.

The call for more male primary-school teachers has long been associated with the educational needs of boys, the importance of positive male role models in schools and the disproportionate number of male and female primary-school teachers internationally. However, little is known about whether or not parents and students actually want more male primary-school teachers and if they do, the reasons they have for wanting more. This paper addresses the under-representation of parents' and students' views by drawing from a study of the perspectives of 97 parents and 184 sixth-grade students from Sydney, Australia. Surveys and semi-structured focus group interviews with boys and girls, and their mothers and fathers revealed an overall perceived social need for more male primary-school teachers. In particular, the paper indicates that male primary-school teachers are considered important for boys; a view consistent with some extant research literature that does not include the views of parents or students. The paper further indicates that parents and students see male primary-school teachers as being beneficial to girls; a matter rarely discussed in any research literature irrespective of the stakeholder group studied.

The variability of results from different automated methods of detection and tracking of extratropical cyclones is assessed in order to identify uncertainties related to the choice of method. Fifteen international teams applied their own algorithms to the same dataset—the period 1989–2009 of interim European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERAInterim) data. This experiment is part of the community project Intercomparison of Mid Latitude Storm Diagnostics (IMILAST; see www.proclim.ch/imilast/index.html). The spread of results for cyclone frequency, intensity, life cycle, and track location is presented to illustrate the impact of using different methods. Globally, methods agree well for geographical distribution in large oceanic regions, interannual variability of cyclone numbers, geographical patterns of strong trends, and distribution shape for many life cycle characteristics. In contrast, the largest disparities exist for the total numbers of cyclones, the detection of weak cyclones, and distribution in some densely populated regions. Consistency between methods is better for strong cyclones than for shallow ones. Two case studies of relatively large, intense cyclones reveal that the identification of the most intense part of the life cycle of these events is robust between methods, but considerable differences exist during the development and the dissolution phases.

Characteristic patterns of cyclogenesis in the southwest Pacific region are identified from a sample of 40 developing cyclones during 1990-94. Cases were chosen objectively to ensure a realistic sampling of typical rather than "ideal" events. A subjective classification based on synoptic-scale upper-tropospheric flow signatures prior to cyclone intensification suggested four classes into which all but three cases fell. Three categories, each containing about a quarter of the population, involved direct coupling with the upper jet. They represent cyclone formation beneath (i) the poleward exit region of a 300-hPa jet upstream from a diffluent trough (class U), (ii) the confluent equatorward entrance region of the upper wind maximum (E), and (iii) the upper jet exit region where the jet is downstream from the upper trough (class D). These are analogous to previously identified categories for the western North Atlantic region. A fourth class involved cyclones forming beneath a preexisting intense upper-level trough (class T) located poleward of the upper-level jet. Class U cyclones, forming within diffluent airflow, exhibited strong cold fronts, weak warm fronts, and a meridional configuration while class E cyclones forming in confluent flow attained a more zonally elongated structure marked by stronger warm fronts and weak cold fronts. Class U cyclones featured frontal evolution similar to the Norwegian cyclone model while class E and D cyclones exhibited characteristics of the Shapiro-Keyser model. These results provide further observational support fbr the emerging paradigm of contrasting frontal and cyclone structure resulting from confluent versus diffluent large-scale flow.

Quasi-Lagmngian budgets of mass, vorticity and heat are calculated following disturbances that form within polar air streams. Observed cases are extracted from the European Centre for Medium-range Weather Forecasts analyses during the First GARP Global Experiment. Model-generated cases are extracted from the simulations of extratropical cyclogenesis by Sandgathe. These polar lows grow primarily through basic baroclinic instability process and exhibit many features of larger maritime extratropical cyclones. Polar lows that originate on the poleward (or Cyclonic—Type C) side of the jet and have considerable midtropospheric positive vorticity advection at formation time are contrasted with lows that form on the equatorward (or Anticyclonic–Type A) side of a nearly straight upper-level jet. The midtropospheric positive vorticity advection must be present to enhance the vertical circulation when the large surface fluxes that are associated with strong outbreaks act to damp the thermal wave amplification. Although latent heat release is an important factor in both types, it is an essential energy source for the Type A low developments on the equatorward side. Although the vorticity balance is initially different for the two types of polar lows, the vorticity budgets during later stages are similar. The beat budget and the thickness tendency equation demonstrate that the self-development process that is present in larger maritime cyclones is also important for polar low intensification. The absence of favorable coupling to a jet stream is the missing factor in a model-generated Type A polar low that failed to develop. Consequently, the mid- and upper-tropospheric wind fields determine which polar lows will intensify to significant amplitudes.

This second of two papers on extratropical transition (ET) over the southwest Pacific Ocean focuses on the variability of ET. A climatology of ET onset based on a previously described objective technique shows that ET commences 15degrees of latitude nearer the equator on average than similar cases from the Northern Hemisphere. Characteristic midlatitude circulation patterns accompanying ET near 30degreesS are identified by means of empirical orthogonal function (EOF) analysis of 50 storms. The first eigenvector pattern, explaining nearly half the circulation variability, expresses relaxed and enhanced pressure gradients south of the storm that define composites similar to "cradled" and "captured" classifications previously described for the southeast Indian Ocean. The second EOF distinguishes redeveloping from weakening storms. Reintensifying storms were located beneath strong cyclonic vorticity advection (CVA) near the equatorward entrance region of an upper jet whereas the upper jet was well to the west of weakening storms.A survey of factors responsible for modulating central sea level pressure change during ET was conducted for the 50 storms. The quantity most strongly correlated with surface development was found to be CVA at the jet level. Extratropical reintensification occurred when the surface cyclone was located beneath the equatorward entrance region of an upper jet for storms between 28degrees and 34degreesS, and beneath the poleward exit jet region for storms farther south. Strongest examples of redevelopment each occurred beneath a potent double jet signature aloft, with maximum storm-relative upper-level CVA located directly above the surface low and net vorticity fluxes reflecting amplification of the upper wave. Weakening storms featured a weakening upper trough directly above the storm, with CVA to the east.

While the value of data for an individual study effort is well understood by the analytic community at large, aggregated worth of data is still astonishingly undervalued by many members of the OR study community. Data can be described as the fundamental elements of information and knowledge that comprises the corporate whole - consequently its aggregated value particularly when addressed in a context larger than an individual study is significantly greater than the sum of the parts. Obtaining data is indispensable. To be effective it must be a continuous process within every study and can be not only very time consuming but also a very expensive factor in the total cost of a study effort. With the aggregate of available data growing with every study the situation becomes even more complex and the case for agreed community wide data management standards and techniques is made even stronger. Without these standards the analyst's ability to find the necessary data for an individual study effort by traditional means decreases exponentially and the ability to reuse existing data in future studies is reduced thereby increasing the cost of data. To help the analyst to face these challenges, the NATO Code of Best Practice for Assessment of Command and Control (COBP) introduced a Data Section. This section already defines the application domains of data engineering, meta data modelling and efficient data re-use. However, the deeper value of these additional efforts - albeit a burden for the single study, especially for the initial efforts at introducing the respective techniques and tools - clearly show up when being seen in the broader context of multiple studies dealing with related topics. This paper extends the application of the COBP data section beyond the scope of a single study into the broadened study community domain, including other Operational Analysts, C3I System Developers, Social Scientists, etc. Therefore, in this paper the necessary methodologies for applying the ideas of the COBP data section, thus enabling the reuse of data across different studies, will be highlighted. A case will be made for a user community requirement for a common data infrastructure including some first ideas for technical implementations.

: While the value of data for an individual study effort is well understood by the analytic community at large, the aggregated worth of data is still astonishingly undervalued by many members of the Operations Research study community. Data can be described as the fundamental elements of information and knowledge that constitute the corporate whole, consequently its aggregated value, particularly when addressed in a context larger than an individual study, is significantly greater than the sum of the parts. Obtaining data is indispensable. To be effective it must be a continuous process within every study. It can be not only very time consuming, but also a very expensive factor in the total cost of a study effort. With the aggregate of available data growing with every study the situation becomes even more complex and the case for agreed-upon, community-wide data management standards and techniques is made even stronger. Without these standards the analyst's ability to find the necessary data for an individual study effort by traditional means decreases exponentially, and the ability to reuse existing data in future studies is reduced, thereby increasing the cost of data. To help the analyst face these challenges, the NATO Code of Best Practice for Assessment of Command and Control (COBP) introduced a Data Section. This section already defines the application domains of data engineering, meta data modeling, and efficient data re-use. However, the deeper value of these additional efforts, albeit a burden for the single study, especially for the initial efforts at introducing the respective techniques and tools, clearly show up when being seen in the broader context of multiple studies dealing with related topics. This paper extends the application of the COBP Data Section beyond the scope of a single study into the broadened study community domain, including other Operational Analysts, C3I System Developers, Social Scientists, etc. (15 briefing charts, 8 refs.)

A significant number of tropical cyclones move into the midlatitudes and transform into extratropical cyclones. This process is generally referred to as extratropical transition ( ET). During ET a cyclone frequently produces intense rainfall and strong winds and has increased forward motion, so that such systems pose a serious threat to land and maritime activities. Changes in the structure of a system as it evolves from a tropical to an extratropical cyclone during ET necessitate changes in forecast strategies. In this paper a brief climatology of ET is given and the challenges associated with forecasting extratropical transition are described in terms of the forecast variables ( track, intensity, surface winds, precipitation) and their impacts ( flooding, bush fires, ocean response). The problems associated with the numerical prediction of ET are discussed. A comprehensive review of the current understanding of the processes involved in ET is presented. Classifications of extratropical transition are described and potential vorticity thinking is presented as an aid to understanding ET. Further sections discuss the interaction between a tropical cyclone and the midlatitude environment, the role of latent heat release, convection and the underlying surface in ET, the structural changes due to frontogenesis, the mechanisms responsible for precipitation, and the energy budget during ET. Finally, a summary of the future directions for research into ET is given.

A database of tropical cyclone best track and intensity information for the southwest Pacific Ocean basin is used to construct a 28-year climatology for tropical cyclones that move into middle latitudes. Of the nine or so tropical cyclones that form each year, an average of about three can be expected to migrate south of 35degreesS, with the greatest fraction in March. Storms entering the Tasman Sea west of New Zealand (NZ) move almost due south on average and retain greater intensity than those to the east of NZ, where storms decay quickly while moving rapidly away to the southeast. Storms east of NZ are embedded in a stronger, more zonal flow than those to the west, which move poleward ahead of a larger-amplitude trough. During El Nino years, tropical cyclones that move into middle latitudes exhibit stronger zonal motion and occur over a wider range of longitudes than during La Nina years. Storm intensity is only weakly correlated with concurrent SST anomalies, suggesting that atmospheric circulation is the dominant influence on storm properties. Average structure changes during extratropical transition (ET) are identified using the NCEP-NCAR reanalysis dataset, for a subset of 33 transitioning storms during 1980-97. Composites are used to construct a three-dimensional conceptual model of the transformation from a mature hurricane to an asymmetric baroclinic midlatitude cyclone. Southwest Pacific tropical cyclones encounter the baroclinic westerlies early in their lives, accounting for their average eastward (and poleward) motion. At maximum average intensity near 20degreesS, baroclinic effects are already important, with warm frontogenesis appearing in the southeast quadrant and outflow aloft into a downstream subtropical wind maximum that moves poleward with the storm. By 25degreesS, the average TC has lost the characteristic symmetric anticyclonic outflow aloft and acquired the characteristics of a baroclinic midlatitude storm, including regions of warm and cold frontogenesis, a vertical motion dipole and a westward tilt with height. From about 30degreesS poleward, a second upper-tropospheric wind maximum appears west of the storm, with strengthening cyclonic vorticity advection aloft. Below about 400 hPa, the storm retains the vertical, warm cyclonic core as it migrates poleward.

While the value of data for an individual study effort is well understood by the analytic community at large, aggregated worth of data is still astonishingly undervalued by many members of the OR study community. Data can be described as the fundamental elements of information and knowledge that comprises the corporate whole consequently its aggregated value particularly when addressed in a context larger than an individual study is significantly greater than the sum of the parts. Obtaining data is indispensable. To be effective it must be a continuous process within every study and can be not only very time consuming but also a very expensive factor in the total cost of a study effort. With the aggregate of available data growing with every study the situation becomes even more complex and the case for agreed community wide data management standards and techniques is made even stronger. Without these standards the analyst’s ability to find the necessary data for an individual study effort by traditional means decreases exponentially and the ability to reuse existing data in future studies is reduced thereby increasing the cost of data. To help the analyst to face these challenges, the NATO Code of Best Practice for Assessment of Command and Control (COBP) introduced a Data Section. This section already defines the application domains of data engineering, meta data modelling and efficient data re-use. However, the deeper value of these additional efforts albeit a burden for the single study, especially for the initial efforts at introducing the respective techniques and tools clearly show up when being seen in the broader context of multiple studies dealing with related topics. This paper extends the application of the COBP data section beyond the scope of a single study into the broadened study community domain, including other Operational Analysts, C3I System Developers, Social Scientists, etc. Therefore, in this paper the necessary methodologies for applying the ideas of the COBP data section, thus enabling the reuse of data across different studies, will be highlighted. A case will be made for a user community requirement for a common data infrastructure including some first ideas for technical implementations. ♣ The contributions to this paper have been conducted on behalf of the Industrieanlagenbetriebsgesellschaft mbH (IABG), Einsteinstr. 20, 85521 Ottobrunn, Germany, where Dr. A. Tolk worked until March 2002. © 2002 Sinclair & Tolk 1 -