Why Web GIS May Not Be Enough: A Case Study with the Virtual Research Vessel

During several decades of investigation, the East Pacific Rise seafloor-spreading center at 9°-10°N has been explored by marine geologists, geophysicists, chemists, and biologists, and has emerged as one of the best studied sections of the global midocean ridge. It is an example of a region for which there is now a great wealth of observational data, results, and data-driven theoretical studies. However, these have yet to be fully utilized, either by research scientists or educators. While the situation is improving, a large amount of data, results, and related theoretical models still exist either in an inert, noninteractive form (e.g., journal publications) or as unlinked and currently incompatible computer data or algorithms. Presented here is the prototype of a computational environment and toolset, called the Virtual Research Vessel, to improve the situation by providing marine scientists and educators with simultaneous access to data, maps, and numerical models. While infrastructure is desired and needed for ready access to data and the resulting maps via web GIS in order to link disparate data sets (data to data), it is argued that data must also be linked to models for better exploration of new relations between observables, refinement of numerical simulations, and the quantitative evaluation of scientific hypotheses. For widespread data access, web GIS is therefore only a preliminary step rather than a final solution, and the ongoing implementation of the Virtual Research Vessel (scheduled for final completion in 2004-2005) is a case study for the midocean ridge community to test the effectiveness of moving beyond the data-to-data mode towards data-to-models and data-to-interpretation.     

Provision,transport and deposition of debris in urban waterways

The transport of woody debris from urban surfaces,through local urban waterways,to constriction and blockage risk locations is not well understood.Flume trials have identified debris and watercourse dimensions as influential factors on debris movement,and large woody debris movement has been traced in the natural rural environment using time series photography,active transponders,and field surveys.Using novel passive transponder technology,small woody debris has been traced through an urban case study watercourse to establish key influential factors on urban debris transport.Through incorporating urban debris transport detail into the source and deposition process,a complete picture of urban debris transport can be created,supporting effective culvert and trash screen design,watercourse maintenance and blockage risk assessment.This case study highlights that factors beyond watercourse depth and velocity are influential in debris movement within an urban watercourse.Debris dimension and source location upstream are shown to significantly affect the potential for debris to reach a downstream constriction,illustrating a possible distance limitation in nuisance flow debris blockage risk.     

Introduction: Toward More Inclusive and Comparative Perspectives in the Histories of Geographical Knowledge

Over the past three decades, feminist historiography of geography has begun to situate women's contribution to the production of geographical knowledge within the histories of geography, at times against the conviction of skeptical colleagues. In this Focus Section introduction, we renew Domosh's (1991a Domosh, M. 1991a. Beyond the frontiers of geographical knowledge. Transactions of the Institute of British Geographers 16 (4): 488–90.[Crossref], [Web of Science ®] , [Google Scholar], 1991b ———. 1991b. Toward a feminist historiography of geography. Transactions of the Institute of British Geographers 16 (1): 95–104.[Crossref], [Web of Science ®] , [Google Scholar]) call for creating more inclusive feminist histories of geography by situating the three focus section articles on the careers and contributions of women in twentieth-century geographical practice and knowledge production in the United Kingdom and the United States within wider debates about diverse, unfamiliar, and previously hidden aspects of geographical knowledge production. We argue that feminist historiography of geography and feminist historical geography could benefit from continuously diversifying inclusive and comparative research perspectives, and from unlocking diverse archives, to enhance understanding of why and how some male and some female gatekeepers have been more supportive of women than others.     

Decomposition of mineral absorption bands using nonlinear least squares curve fitting: Application to Martian meteorites and CRISM data

This study advances curve-fitting modeling of absorption bands of reflectance spectra and applies this new model to spectra of Martian meteorites ALH 84001 and EETA 79001 and data from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). This study also details a recently introduced automated parameter initialization technique. We assess the performance of this automated procedure by comparing it to the currently available initialization method and perform a sensitivity analysis of the fit results to variation in initial guesses. We explore the issues related to the removal of the continuum, offer guidelines for continuum removal when modeling the absorptions and explore different continuum-removal techniques. We further evaluate the suitability of curve fitting techniques using Gaussians/Modified Gaussians to decompose spectra into individual end-member bands. We show that nonlinear least squares techniques such as the Levenberg–Marquardt algorithm achieve comparable results to the MGM model (Sunshine and Pieters, 1993, Sunshine et al., 1990) for meteorite spectra. Finally we use Gaussian modeling to fit CRISM spectra of pyroxene and olivine-rich terrains on Mars. Analysis of CRISM spectra of two regions show that the pyroxene-dominated rock spectra measured at Juventae Chasma were modeled well with low Ca pyroxene, while the pyroxene-rich spectra acquired at Libya Montes required both low-Ca and high-Ca pyroxene for a good fit.     

Late Holocene paleohydrology of Kluane Lake, Yukon Territory, Canada

We have gained new insight into the dynamic late Holocene paleohydrology and paleolimnology of Kluane Lake by reconstructing lakewater δ¹⁸O using sediment cellulose as an oxygen-isotope archive. Our data suggest that the lake was regularly open hydrologically between 5000 and 1000 cal year BP, although with substantially lower water levels and with greater evaporative loss in relation to inflow than under contemporary conditions. During part of this period the lake was meromictic and may have undergone intermittent hydrologic closure, but southward drainage to the Pacific Ocean via the Alsek River system was generally maintained. Isotopic evidence confirms that Kluane Lake underwent complete hydrologic closure 430–300 cal year BP (AD 1520–1650) after a major advance of Kaskawulsh Glacier blocked southward drainage. Closure persisted as the lake overtopped the Duke River fan, initiating northward drainage to the Bering Sea via the Yukon River system. Although incision of the new outlet channel led to a rapid decline in lake level, northward discharge via the Kluane River has been maintained for the past three centuries because of abundant inflow from the Slims River. Substantial quantities of glacial meltwater and seasonal runoff continue to drain via the Slims River from Kaskawulsh Glacier and its catchment in the St. Elias Mountains. During this period Kluane River has also become an important route for migrating anadromous salmon. The modern isotope hydrology of Kluane Lake confirms that its current positive water balance is highly dependent on discharge from Slims River. Declining glacial meltwater contributions to Slims River will likely lead to lower water levels in Kluane Lake over the coming decades and possible re-establishment of intermittent or perennial hydrologic closure.     

Asymmetry in an uneven place: migrants’ lifestyles,social capital,and self-rated health status in James Town,Accra

This exploratory study examines how migrants’ lifestyles are associated with subjective assessment of their health status in a relatively poor urban neighborhood in Accra. For more than half a century, urban centers have been on the receiving end of internal migrants in Ghana with Accra, Kumasi, and Sekondi-Takoradi receiving the lion’s share. However, a lot of migrants end up in poor neighborhoods due to inability to afford relatively costly rents in the better residential areas in the cities. Migrants who live on the margins of society are adversely impacted by poor environmental conditions that make them susceptible to environmentally-induced diseases such as malaria, cholera, and typhoid. While the poverty, health, and place research in Accra, Ghana, have focused on spatial distribution of inequalities in health, burden of sexual ill health, double burden of diseases, environment, wealth and health relationship, as well as income and health connections, there is paucity of research on association between the daily lifestyles of migrants in poor urban neighborhoods and their health status. Specifically on lifestyle and contextual factors, we examine (1) eating and drinking behavior, (2) perception of environmental factors, (3) attitudes and practices during illnesses, and (4) physical activities. Results from Ordinal Logit Regression models suggest that the key predictors of self-rated health status are: (1) socio-demographic elements like length of stay, job type, and religiosity; and (2) eating and drinking behavior—frequency of buying food from food vendors, and (3) social capital.     

Choreographing a different dance: placing research in the public arena

Geographers increasingly advocate placing research in the public arena and the creation of work that is useful for public policy makers. Existing literature indicates some approaches that have bearing on these goals, such as using participatory action research, clarifying positionality, and attending to the nature of discourse. It does not, however, generally offer empirical cases of addressing the goals being advocated. This article narrates an experience of a collaborative effort among two institutes for research on women and a community funding agency as they created and disseminated research aiming to influence public opinion and foster advocacy in support of policies to improve women’s lives. Among the issues addressed are the importance of networking, of identifying effective partners, of adapting research to incorporate the priorities of stakeholders, and of engaging the support of media professionals. It discusses barriers encountered, strategies adopted to address them, and compromises in the process.     

Arsenic in the groundwater of Ouro Preto (Brazil): its temporal behavior as influenced by the hydric regime and hydrogeology

In the city of Ouro Preto (MG), water catchment for public supply originates from superficial drainage, springs, old abandoned mines and some driven wells. In the rocks of the region, As is originally found in gold-enriched sulphide-bearing mineral deposits. The weathering process introduces As into the hydrological system by dissolution of this element into the leachate. Measurement of the As content in the groundwater of some catchments was carried out during 1 year and these measurements demonstrated high As content—up to 224 μg L⁻¹ of As(V)—during the rainy season (the maximum concentration limit according to World Health Organization is 10 μg L⁻¹). Lower values were observed during the dry season and in some sampling stations, As was not even detected. The As concentration variability during 1 year shows a strict and direct relationship to seasonal and hydrological conditions. For city authorities, responsible for public water supply, it is necessary to perform a complete inventory of the water sources used and constantly monitor the As content in the water.     

Stratigraphic and structural controls on groundwater salinity variations in the Poso Creek Oil Field,Kern County,California, USA

Hydrogeology Journal - Groundwater total dissolved solids (TDS) distribution was mapped with a three-dimensional (3D) model, and it was found that TDS variability is largely controlled by...