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David M. Schultz

A 14-week laboratory course at the University of Helsinki was offered to improve undergraduate and graduate students' writing and speaking skills, as well as their scientific skills. To emphasize active learning, the course avoided long lecture sessions and featured intensive homework assignments and in-class exercises. Examples of these assignments included a title-writing exercise, brainstorming, peer-reviewing, and précis. To reveal their attitudes about and approaches toward scientific writing, gauge their opinions and knowledge of scientific communication skills, and guide the course content, the students completed a survey during week 1. The survey asked questions on such varied topics as the use of first-person pronouns in scientific writing, willingness to publish in open-access journals, and attitudes regarding coauthorship between students and professors. A final in-class presentation involved the students asking for funding for their research project from a panel of nonspecialists, forcing the students to convince others of the value of their research. The challenges of teaching this kind of laboratory course included encouraging student participation and the amount of grading, although these challenges could be overcome by small-group exercises and changing the approach to grading, respectively. Finally, this article discusses the opportunities for these exercises to be applied to regular curriculum courses in the atmospheric sciences.

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David M. Schultz

Characteristics of 63 journals publishing peer-reviewed articles on atmospheric science were collected from online information and through a survey e-mailed to the journals. The rate that submitted manuscripts were rejected for publication (hereafter, the rejection rate) was available for 47 (75%) of the journals. Although the range in rejection rates is quite large (2%–91%), most journals reject between 25% and 60% of submitted manuscripts, with a mean of 38.7%, a result of more than 6,000 manuscripts a year rejected for publication. Some journals have a policy of the editor vigorously rejecting manuscripts without peer review, whereas others send either all or nearly all of the manuscripts out for peer review. Measures of journal volume and quality (i.e., number of submissions, number of published articles, number of citations, impact factor, immediacy index, article half-life) show little, if any, relationship to rejection rates, indicating that rejection rates are not higher for journals of higher perceived quality. Nonprofit journals have significantly lower rejection rates than for-profit journals, and journals with page charges have significantly lower rejection rates than those without page charges. That few journals have rejection rates less than 25% indicates that some minimum standard for quality of submitted manuscripts is met at nearly all journals, which is some of the evidence for consensus (defined as the shared conceptions of research problems and techniques) within the atmospheric sciences. Because many factors go into choosing a journal for manuscript submission, the results of this study should not be used as a menu for authors to decide to which journals they should submit their manuscripts.

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David M. Schultz

Based on a talk given at the sixth annual meeting of the Atmospheric Science Librarians International, this paper explores the author;s experiences performing reviews of the scientific literature as a tool to advancing meteorology and studying the history of science. Three phases of performing literature searches with varying degrees of interaction with a research librarian are considered: do it yourself, librarian assisted, and librarian as collaborator. Examples are given for each phase: occluded fronts, conditional symmetric instability, and static instability terminology, respectively. Electronic availability of information is changing the relationship between scientists and librarians. Yet, despite these changes, books on library shelves and knowledgeable human librarians remain essential to the scientific enterprise.

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David M. Schultz and Geraint Vaughan

Traditionally, the formation of an occluded front during the occlusion process in extratropical cyclones has been viewed as the catch-up of a faster-moving cold front to a slower-moving warm front separating the warm-sector air from the low center, as first described in the Norwegian cyclone model over 90 yr ago. In this article, the conventional wisdom, or the commonly held beliefs originating from the Norwegian cyclone model, about occluded fronts and the occlusion process are critically examined. The following four tenets of this conventional wisdom are addressed. First, the occlusion process is better described not by catch-up, but by the wrapping up and lengthening of the warm-air tongue as a result of deformation and rotation around the low center. Second, the merger of the cold front and warm front does not result in the frontal zone with the warmer air ascending over the other frontal zone. Instead, the occluded frontal zone tilts over the more statically stable frontal zone. Because a warmfrontal zone tends to be more stable than a cold-frontal zone, this process usually produces a warm-type occlusion, confirming that cold-type occlusions are less common than warm-type occlusions. Third, occlusion does not mean that the cyclone has stopped deepening, because many cyclones continue to deepen 10–30 mb for 12–36 h after the formation of the occluded front. Fourth, clouds and precipitation associated with occluded fronts differ from their widespread stratiform depiction in textbooks. Embedded precipitation bands may be parallel to the front, and little relationship may exist between the fronts and the cloud mass. These four tenets help to explain anomalies in the Norwegian cyclone model, such as how occluded fronts that spiral around the low center do not require catch-up to form, how Shapiro–Keyser cyclones undergo occlusion, why some cyclones do not form occluded fronts, how some cyclones deepen after occlusion, why few cold-type occlusions have been observed, and why occluded cyclones are often associated with heavy precipitation. This reexamination of conventional wisdom leads to a new paradigm for occluded fronts and occluded cyclones.

A supplement to this article is available online:

DOI: 10.1175/2010BAMS3057.2

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Mary Golden and David M. Schultz

A survey of 310 reviewers for Monthly Weather Review addresses how much time and effort goes into the peer-review process and provides insight into how reviewers function. Using these data, the individual and collective contributions of volunteer peer reviewers to the peer-review process can be determined. Individually, respondents to the survey review an average of 2 manuscripts a year for Monthly Weather Review, 4 manuscripts a year for AMS journals, and 8 manuscripts a year in total, although some review more than 20 manuscripts a year. Each review takes an average of 9.6 h. Summing the individual contributions of the reviewers, respondents averaged 18 h yr−1 performing reviews for Monthly Weather Review, 36 h yr−1 for AMS journals, and 63 h yr−1 for all journals. The collective time that all of the reviewers put into the peer-review process for all manuscripts submitted to Monthly Weather Review for each year amounts to 362,179 h, or more than 4 years of voluntary labor valued at over $2.34 million. Nearly all respondents (95%) are comfortable with their current load, but only 30% said that they would be willing to perform more reviews. Because the number of submissions to journals has been increasing over time and is unlikely to decrease in the near future, this burden is anticipated to grow. Options for reducing the burden include using fewer reviewers per manuscript, increasing the number of unilateral decisions made by editors, and increasing the size of the reviewer pool (particularly from active retired and early-career scientists).

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David M. Schultz and Daniel Keyser

Abstract

Two widely accepted conceptual models of extratropical cyclone structure and evolution exist: the Norwegian and Shapiro–Keyser cyclone models. The Norwegian cyclone model was developed around 1920 by the Bergen School meteorologists. This model has come to feature an acute angle between the cold and warm fronts, with the reduction in the area of the warm sector during the evolution of the cyclone corresponding to the formation of an occluded front. The Shapiro–Keyser cyclone model was developed around 1990 and was motivated by the recognition of alternative frontal structures depicted in model simulations and observations of rapidly developing extratropical cyclones. This model features a right angle between the cold and warm fronts (T-bone), a weakening of the poleward portion of the cold front (frontal fracture), an extension of the warm or occluded front to the rear of and around the cyclone (bent-back front), and the wrapping around of the bent-back front to form a warm-core seclusion of post-cold-frontal air. Although the Norwegian cyclone model preceded the Shapiro–Keyser cyclone model by 70 years, antecedents of features of the Shapiro–Keyser cyclone model were apparent in observations, analyses, and conceptual models presented by the Bergen School meteorologists, their adherents, and their progeny. These “lost” antecedents are collected here for the first time to show that the Bergen School meteorologists were aware of them, although not all of the antecedents survived until their reintroduction into the Shapiro–Keyser cyclone model in 1990. Thus, the Shapiro–Keyser cyclone model can be viewed as a synthesis of various elements of cyclone structure and evolution recognized by the Bergen School meteorologists.

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Carl M. Thomas and David M. Schultz

Abstract

Fronts can be computed from gridded datasets such as numerical model output and reanalyses, resulting in automated surface frontal charts and climatologies. Defining automated fronts requires quantities (e.g., potential temperature, equivalent potential temperature, wind shifts) and kinematic functions (e.g., gradient, thermal front parameter, and frontogenesis). Which are the most appropriate to use in different applications remains an open question. This question is investigated using two quantities (potential temperature and equivalent potential temperature) and three functions (magnitude of the horizontal gradient, thermal front parameter, and frontogenesis) from both the context of real-time surface analysis and climatologies from 38 years of reanalyses. The strengths of potential temperature to identify fronts are that it represents the thermal gradients and its direct association with the kinematics and dynamics of fronts. Although climatologies using potential temperature show features associated with extratropical cyclones in the storm tracks, climatologies using equivalent potential temperature include moisture gradients within air masses, most notably at low latitudes that are unrelated to the traditional definition of a front, but may be representative of a broader definition of an airmass boundary. These results help to explain previously published frontal climatologies featuring maxima of fronts in the subtropics and tropics. The best function depends upon the purpose of the analysis, but Petterssen frontogenesis is attractive, both for real-time analysis and long-term climatologies, in part because of its link to the kinematics and dynamics of fronts. Finally, this study challenges the conventional definition of a front as an airmass boundary and suggests that a new, dynamically based definition would be useful for some applications.

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Bogdan Antonescu, Hugo M. A. M. Ricketts, and David M. Schultz

Abstract

Alfred Wegener (1880–1930) was a leading geophysicist, atmospheric scientist, and an Arctic explorer who is mainly remembered today for his contributions to the theory of continental drift. Less well known are his contributions to research on tornadoes in Europe. Published 100 years ago, book Wind- und Wasserhosen in Europa (Tornadoes and Waterspouts in Europe) is an impressive synthesis of knowledge on tornadoes and is considered the first modern pan-European tornado climatology, with 258 reports from 1456 to 1913. Unfortunately, Wegener’s book was overlooked after the 1950s amid declining interest in tornadoes by European researchers and meteorologists. The recent revival of tornado studies in Europe invites a reflection on Wegener’s book. Using a relatively small dataset, Wegener was able to describe characteristics of tornadoes (e.g., direction of movement, speed, rotation, formation mechanism), as well as their frequency of occurrence and climatology, comparable with the results from modern tornado climatologies. Wegener’s lasting scientific contributions to tornado research are presented in the context of European research on this topic. Specifically, his book showed the utility of reports from citizen scientists and inspired other researchers, namely, Johannes Letzmann, who continued to study European tornadoes after Wegener’s death.

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Christopher M. Godfrey, Daniel S. Wilks, and David M. Schultz

The existence of the January thaw, a purported systematic anomalous warming in daily mean temperatures at northeastern U.S. stations during late January, is investigated quantitatively. A key idea in the analysis is that winter temperatures are intrinsically more variable, and this property must be accounted for when judging the unusualness of excursions of daily mean temperatures from a smooth climatic mean function. Accordingly the daily mean temperature departures are expressed nondimensionally by dividing by appropriate standard deviations that vary through the year. The warm excursion in observed records for late January is not always the most extreme such excursion in the nondimensionalized data, even when the definition of “excursion” is optimized to emphasize the late January event. Hypothesis tests based on time series models with smoothly varying climatologies (i.e., with no anomalous features such as the January thaw, by construction) are used to evaluate the statistical significance of the observed January thaws. The synthetic series produce many apparent events of similar character and magnitudes, although occurring randomly throughout the year and equally divided between warm and cool deviations. It is thus concluded that the effects of sampling in finite climate records are wholly adequate to account for the existence of January thaw “features” in northeastern U.S. temperature data.

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Neil A. Stuart, David M. Schultz, and Gary Klein

The Second Forum on the Future Role of the Human in the Forecast Process occurred on 2–3 August 2005 at the American Meteorological Society's Weather Analysis and Forecasting Conference in Washington, D.C. The forum consisted of three sessions. This paper discusses the second session, featuring three presentations on the cognitive and psychological aspects of expert weather forecasters. The first presentation discussed the learning gap between students (goal seekers) and teachers (knowledge seekers)—a similar gap exists between forecasters and researchers. In order to most effectively train students or forecasters, teachers must be able to teach across this gap using some methods described within. The second presentation discussed the heuristics involved in weather forecasting and decision making under time constraints and uncertainty. The final presentation classified the spectrum of forecasters from intuitive scientists to the disengaged. How information technology can best be adapted so as not to inhibit intuitive scientists from their mental modeling of weather scenarios is described. Forecasters must continuously refine their skills through education and training, and be aware of the heuristic contributions to the forecast process, to maintain expertise and have the best chance of ensuring a dynamic role in the future forecast process.

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