AgClimate: a case study in participatory decision support system development

Potential economic benefit exists from the use of seasonal climate forecasts in agriculture. To assess potential end user attitudes toward and interests in climate data, and to provide inputs from users to the development of decision support tools, we conducted a series of surveys. Survey results affected the design, development, and enhancement of AgClimate, a web-based decision support system for minimizing climate risks to agriculture. The overall process is an example of how decision makers can participate in the research process, thereby improving the value and relevance of research products such as decision support systems.     

Governmentality and security in the US President’s Emergency Plan for AIDS Relief (PEPFAR)

This article offers a critical theoretical exploration of the US President’s Emergency Plan for AIDS Relief (PEPFAR). The article examines the background to PEPFAR and its reauthorization in Washington DC in 2008 through the conceptual lens of governmentality. Building on existing work, it interprets PEPFAR as a programme for securing the welfare of populations. It also qualifies and extends this work in the following ways. Rather than representing a break with the history of geopolitics, it argues that PEPFAR emerged out of accommodations between geopolitics and governmentality. This point is developed through two takes on geopolitics, first in terms of the projection of sovereign power, and second in terms of articulations between PEPFAR and geopolitical economies of global health. The article suggests, first, that the geopolitics of sovereign power shaped the timing, scale and form of PEPFAR, and second, that PEPFAR articulated with geopolitical economies of global health through its mobilization of US-based corporations, non-governmental and faith-based organizations. The article extends existing work by examining the role of critical mobilizations in shaping PEPFAR, both in relation to questions of political economy and the contentious politics of life. Reflecting on the politics of global health, it considers the prospects for using ideas of security and the international response to HIV/AIDS as stepping stones towards the development of broad-based health systems.     

Traversing nature's danger zone: getting up close with Sumatra's volcanoes

The Indonesian island of Sumatra, located in one of the most active zones of the Pacific Ring of Fire, is characterized by a chain of subduction‐zone volcanoes which extend the entire length of the island. As a group of volcanic geochemists, we embarked upon a five‐week sampling expedition to these exotic, remote, and in part explosive volcanoes (SAGE 2010; Sumatran Arc Geochemical Expedition). We set out to collect rock and gas samples from 17 volcanic centres from the Sumatran segment of the Sunda arc system, with the aim of obtaining a regionally significant sample set that will allow quantification of the respective roles of mantle versus crustal sources to magma genesis along the strike of the arc. Here we document our geological journey through Sumatra's unpredictable terrain, including the many challenges faced when working on active volcanoes in pristine tropical climes.     

Forecasting flows in Apalachicola River using neural networks

Forecasting river flow is important to water resources management and planning. In this study, an artificial neural network (ANN) model was successfully developed to forecast river flow in Apalachicola River. The model used a feed‐forward, back‐propagation network structure with an optimized conjugated training algorithm. Using long‐term observations of rainfall and river flow during 1939–2000, the ANN model was satisfactorily trained and verified. Model predictions of river flow match well with the observations. The correlation coefficients between forecasting and observation for daily, monthly, quarterly and yearly flow forecasting are 0·98, 0·95, 0·91 and 0·83, respectively. Results of the forecasted flow rates from the ANN model were compared with those from a traditional autoregressive integrated moving average (ARIMA) forecasting model. Results indicate that the ANN model provides better accuracy in forecasting river flow than does the ARIMA model. Copyright © 2004 John Wiley & Sons, Ltd.     

Spatial aspects of MRSA epidemiology: a case study using stochastic simulation,kernel estimation and SaTScan

The identification of disease clusters in space or space–time is of vital importance for public health policy and action. In the case of methicillin‐resistant Staphylococcus aureus (MRSA), it is particularly important to distinguish between community and health care‐associated infections, and to identify reservoirs of infection. 832 cases of MRSA in the West Midlands (UK) were tested for clustering and evidence of community transmission, after being geo‐located to the centroids of UK unit postcodes (postal areas roughly equivalent to Zip+4 zip code areas). An age‐stratified analysis was also carried out at the coarser spatial resolution of UK Census Output Areas. Stochastic simulation and kernel density estimation were combined to identify significant local clusters of MRSA (p<0.025), which were supported by SaTScan spatial and spatio‐temporal scan. In order to investigate local sampling effort, a spatial ‘random labelling’ approach was used, with MRSA as cases and MSSA (methicillin‐sensitive S. aureus) as controls. Heavy sampling in general was a response to MRSA outbreaks, which in turn appeared to be associated with medical care environments. The significance of clusters identified by kernel estimation was independently supported by information on the locations and client groups of nursing homes, and by preliminary molecular typing of isolates. In the absence of occupational/lifestyle data on patients, the assumption was made that an individual's location and consequent risk is adequately represented by their residential postcode. The problems of this assumption are discussed, with recommendations for future data collection.     

Weather Forecasts are for Wimps: Why Water Resource Managers Do Not Use Climate Forecasts

Short-term climate forecasting offers the promise of improved hydrologic management strategies. However, water resource managers in the United States have proven reluctant to incorporate them in decision making. While managers usually cite poor reliability of the forecasts as the reason for this, they are seldom able to demonstrate knowledge of the actual performance of forecasts or to consistently articulate the level of reliability that they would require. Analysis of three case studies in California, the Pacific Northwest, and metro Washington DC identifies institutional reasons that appear to lie behind managers reluctance to use the forecasts. These include traditional reliance on large built infrastructure, organizational conservatism and complexity, mismatch of temporal and spatial scales of forecasts to management needs, political disincentives to innovation, and regulatory constraints. The paper concludes that wider acceptance of the forecasts will depend on their being incorporated in existing organizational routines and industrial codes and practices, as well as changes in management incentives to innovation. Finer spatial resolution of forecasts and the regional integration of multi-agency functions would also enhance their usability.The title of this article is taken from an advertising slogan for the Oldsmobile Bravura SUV.     

Ion microprobe measurement of strontium isotopes in calcium carbonate with application to salmon otoliths

The ion microprobe has the capability to generate high resolution, high precision isotopic measurements, but analysis of the isotopic composition of strontium, as measured by the ⁸⁷Sr/⁸⁶Sr ratio, has been hindered by isobaric interferences. Here we report the first high precision measurements of ⁸⁷Sr/⁸⁶Sr by ion microprobe in calcium carbonate samples with moderate Sr concentrations. We use the high mass resolving power (7000 to 9000 M.R.P.) of the SHRIMP-RG ion microprobe in combination with its high transmission to reduce the number of interfering species while maintaining sufficiently high count rates for precise isotopic measurements. The isobaric interferences are characterized by peak modeling and repeated analyses of standards. We demonstrate that by sample-standard bracketing, ⁸⁷Sr/⁸⁶Sr ratios can be measured in inorganic and biogenic carbonates with Sr concentrations between 400 and 1500 ppm with ∼2‰ external precision (2σ) for a single analysis, and subpermil external precision with repeated analyses. Explicit correction for isobaric interferences (peak-stripping) is found to be less accurate and precise than sample-standard bracketing. Spatial resolution is ∼25 μm laterally and 2 μm deep for a single analysis, consuming on the order of 2 ng of material. The method is tested on otoliths from salmon to demonstrate its accuracy and utility. In these growth-banded aragonitic structures, one-week temporal resolution can be achieved. The analytical method should be applicable to other calcium carbonate samples with similar Sr concentrations.     

Testing Sr/Sr as a paleosalinity indicator on mixed marine, brackish-water and terrestrial vertebrate skeletal apatite in late Paleocene-early Eocene near-coastal sediments, Mississippi

Mixed marine, brackish-water and terrestrial vertebrate skeletal apatite is found in the late Paleocene-early Eocene Tuscahoma and Bashi Formations of Mississippi. The co-Occurrence in these near-coastal marine deposits of skeletal apatite with different provenances offers a unique opportunity for unraveling the effects of diagenesis on apatite ⁸⁷Sr/⁸⁶Sr composition, with bearings on the use of this isotope pair as paleosalinity indicator. The results show that the Sr isotopes of all originally poorly ordered phases of skeletal apatite have extensively re-equilibrated with pore water with significantly lower ⁸⁷Sr/⁸⁶Sr ratios than late Paleocene-early Eocene seawater. For example, marine shark and ray teeth from the Bashi Formation all have clearly nonmarine ⁸⁷Sr/⁸⁶Sr ratios, 0.7073-0.7075, compared with a coeval seawater ratio in the range 0.7077-0.7078. However, separated shark tooth enamel, with a high original crystallinity, appears to have retained all or most of its in vivo Sr isotopic signature until the present. Here we also show that ⁸⁷Sr/⁸⁶Sr results on recent vertebrate skeletal material from different environments are in good agreement with expected values for respective habitat.

Earlier analyses of calcite material from the Bashi Formation indicated the existence of a shift in seawater ⁸⁷Sr/⁸⁶Sr to a lower value at the Paleocene-Eocene boundary. The strong influence of pore water with low, nonmarine ⁸⁷Sr/⁸⁶Sr on the apatite in the Bashi Formation suggests that the proposed isotopic shift may be an artifact related to diagenetic processes.     

The residential segregation of San Antonio,Texas in 1910: an analysis of ethno-racial and occupational spatial patterns with the colocation quotient

The segregation of cities can be traced to a time when the compartmentalization of space and people was based on factors other than race. In segregation research, one of the limiting factors has always been the geographic scale of the data, and the limited knowledge that exists of segregation patterns when the household is the unit of analysis. Historical census data provides the opportunity to analyze the disaggregated information, and this paper does so with San Antonio during 1910. A spatial analysis of residential segregation based on race, ethnicity, and occupations is carried out with the colocation quotient to map and measure the attraction of residents. Results reveal the presence of residential segregation patterns on different sectors of the city based on households’ ethno-racial and occupational attributes; therefore, providing evidence of the existence of residential segregation prior to the commonly cited determinants of segregation of the 20th century.     

Abundance of larval rainbow smelt (Osmerus mordax) in relation to the maximum turbidity zone and associated macroplanktonic fauna of the middle St. Lawrence estuary

We tested the hypothesis that the distribution and retention of larval smelt (Osmerus mordax) in the middle estuary of the St. Lawrence River is related to the maintenance of other planktonic organisms in the maximum turbidity zone (MTZ). We documented the horizontal and vertical distribution of larval smelt, macrozooplankton, and suspended particulate matter over four tidal cycles at each of three stations located along the major axis of the turbid upstream portion of the middle estuary. During summer, the turbid, warm, and low salinity waters of the two upstream stations were characterized byNeomysis americana, Gammarus sp. (principallyG. tigrinus), larval smelt,Mysis stenolepsis, andCrangon septemspinosus. The more stratified and less turbid waters of the downstream station were characterized by a coastal marine macrozooplanktonic community and the almost total absence of smelt larvae. Within the MTZ, the distribution ofN. americana coincided with the zone of longest average advective replacement times (null zone). Smelt larvae were distributed further upstream within the MTZ thanN. americana. Overall, larger larvae were distributed further upstream than smaller larvae. The relationship between turbidity and larval density at a specific time was weak (due to resuspension of sediments but not larvae), but the mechanism responsible for producing higher residence times for both sediment and larvae on a longer term basis appears the same. The daily movement and skewed nature of the null zone (due to the general cyclonic circulation of the middle estuary) defines a geographic zone over which the larval smelt population oscillates and remains despite the mean downstream velocities over the water column.