Multiple Equilibria in a Single-Column Model of the Tropical Atmosphere

A single-column model run under the weak temperature gradient approximation, a parameterization of large-scale dynamics appropriate for the tropical atmosphere, is shown to have multiple stable equilibria. Under conditions permitting persistent deep convection, the model has a statistically steady state in which such convection occurs, as well as an extremely dry state in which convection does not occur. Which state is reached depends on the initial moisture profile.Comment: Submitted to Geophysical Research Letter

Teaching with WorldCat Local: What\u27s Different?

This presentation discusses a recent study examining how WorldCat Local impacts library instruction. WorldCat Local is a library catalog discovery layer offered by OCLC. It has proven popular with academic libraries since its initial launch in 2008. This system is not merely a more flexible catalog interface, however; rather, it provides users with simplified search capabilities and access to multiple types of resources such as articles drawn from databases as well as catalog records drawn from an OPAC. Thus, WorldCat Local can be characterized as a meta-search system. Meta-search systems have long been at the center of a debate in library instruction contexts. This debate centers on the question of whether such systems ultimately help or hinder students\u27 successful acquisition of information literacy skills and concepts. The study revealed that librarians are struggling to adapt this radically different resource to existing teaching schemas, with mixed results. Librarians whose institutions have implemented, or which may implement WorldCat Local or another meta-search system will benefit by learning of the experiences, pedagogical approaches, and concerns of librarians who teach varied patron populations using this tool. Because adapting to new resources requires considerable experimentation and reflection, attendees will learn from the experiences of others and will gain a sense of how WorldCat Local can support information literacy. The presentation will additionally focus upon suggested teaching methods for harnessing the advantages of this resource and will discuss emerging best practice for teaching with WorldCat Local

Localness in climate change

Climate change is a global problem, yet it is experienced at the local scale, in ways that are both place-specific and specific to the accidents of weather history. This article takes the dichotomy between the global and the local as a starting point to develop a critique of the normative approach within climate science, which is global in various ways and thereby fails to bring meaning to the local. The article discusses the ethical choices implicit in the current paradigm of climate prediction, how irreducible uncertainty at the local scale can be managed by suitable reframing of the scientific questions, and some particular epistemic considerations that apply to climate change in the global South. The article argues for an elevation of the narrative and for a demotion of the probabilistic from its place of privilege in the construction and communication of our understanding of global warming and its local consequences

Consumption Externalities and Economic Welfare

The distinction between technological and pecuniary externalities, usually made in production, can also be applied to consumption. Technological externalities create resource misallocations while pecuniary externalities do not. Taking a household production approach to consumption, this paper shows that many cases in which there are external effects on people's utility functions are pecuniary externalities, and public policy should ignore them. The economic literature has been inconsistent in its treatment of pecuniary consumption externalities, and this paper provides a framework for analysis in cases where the actions of some people affect the utility of others.Consumption; Economic Welfare; Externalities; Welfare

Vulvovaginal Trichosporonosis

Objective: Isolation of Trichosporon species from vaginal secretions is a rare event, and no data are available on its pathogenic role. A case series is presented to determine the pathogenic role of Trichosporon species in vulvovaginal infections. Methods: We performed a retrospective chart review of patients seen in the W.S.U. Vaginitis Clinic in order to identify patients from whom Trichosporon species were isolated. Results: Between 1986 and 2001, a total of 13 patients had a total of 18 positive vaginal cultures for Trichosporon species. All 18 vaginal isolates were T. inkin. In general, positive vaginal cultures were accompanied by low yeast colony counts. Four out of 18 positive T. inkin cultures were obtained from visits by asymptomatic patients. Of the remaining 14 positive T. inkin cultures from patients with symptoms, nine out of 14 cultures had other diagnoses (Candida albicans, six cases; bacterial vaginosis, two cases; Trichomonas, one case). Five positive T. inkin cultures were obtained from visits at which patients had symptoms and no associated diagnosis. In only one of the five episodes could we establish a clear pathogenic role for Trichosporon. In this case the patient was treated with boric acid and had resolution of symptoms and a negative culture at follow-up. In-vitro susceptibility tests revealed that T. inkin was resistant to flucytosine and susceptible to all topical and oral azoles. Conclusions: T. inkin is occasionally found in vulvovaginal cultures and is usually a non-pathogen. Transient colonization tended to occur in women, usually of African—American origin, with major perturbations in vaginal flora (bacterial vaginosis and trichomoniasis) and increased pH. Pathogenic consequences of Trichosporon colonization appear to be rare

Tropical cyclone genesis potential index in climate models

The potential for tropical cyclogenesis in a given ocean basin during its active season has been represented by genesis potential indices, empirically determined functions of large-scale environmental variables which influence tropical cyclone (TC) genesis. Here we examine the ability of some of today's atmospheric climate models, forced with historical observed SST over a multidecadal hindcast period, to reproduce observed values and patterns of one such genesis potential index (GP), as well as whether the GP in a given model is a good predictor of the number of TCs generated by that model. The effect of the horizontal resolution of a climate model on its GP is explored. The five analysed models are capable of reproducing the observed seasonal phasing of GP in a given region, but most of them them have a higher GP than observed. Each model has its own unique relationship between climatological GP and climatological TC number; a larger climatological GP in one model compared to others does not imply that that model has a larger climatological number of TCs. The differences among the models in the climatology of TC number thus appear to be related primarily to differences in the dynamics of the simulated storms themselves, rather than to differences in the simulated large-scale environment for genesis. The correlation of interannual anomalies in GP and number of TCs in a given basin also differs significantly from one model to the next. Experiments using the ECHAM5 model at different horizontal resolutions indicate that as resolution increases, model GP also tends to increase. Most of this increase is realized between T42 and T63

Northern hemisphere tropical cyclones during the quasi-El Niño of late 2014

During the second half of 2014, the tropical Pacific was in a state marginally consistent with El Niño. While oceanic indicators were indicative of a weak El Niño event, a number of atmospheric indicators were not, and a number of forecast centers did not declare an El Niño. Nonetheless, the most active tropical cyclone basins of the northern hemisphere—those of the North Atlantic and Pacific—showed tropical cyclone statistics that in some respects were consistent with El Niño. In particular, the numbers of relatively intense storms in the four basins considered—major hurricanes in the Eastern North Pacific and North Atlantic, super typhoons in the Western North Pacific, and hurricanes in the Central North Pacific—formed a pattern strongly consistent with El Niño