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Presents information on a study which proposed a method for the end-management of old landfills in Finland which is based on the utilization of forest and paper industry wastes flows. Landfill construction from waste material flows; Environmental benefits of landfill management through waste utilization; Difficulties in waste utilization.

Future changes in land use/land cover (LULC) and climate (CC) affect watershed hydrology. Despite past research on estimating such changes, studies on the impacts of both these nonstationary stressors on urban watersheds have been limited. Urban watersheds have several important details such as hydraulic infrastructure that call for fine-scale models to predict the impacts of LULC and CC on watershed hydrology. In this paper, a fine-scale hydrologic model—Personal Computer Storm Water Management Model (PCSWMM)—was applied to predict the individual and joint impacts of LULC changes and CC on surface runoff attributes (peak and volume) in 3800 urban subwatersheds in Midwest Florida. The subwatersheds a range of characteristics in terms of drainage area, surface imperviousness, ground slope and LULC distribution. The PCSWMM also represented several hydraulic structures (e.g., ponds and pipes) across the subwatersheds. We analyzed changes in the runoff attributes to determine which stressor is most responsible for the changes and what subwatersheds are mostly sensitive to such changes. Six 24-h design rainfall events (5- to 200-year recurrence intervals) were studied under historical (2010) and future (year 2070) climate and LULC. We evaluated the response of the subwatersheds in terms of runoff peak and volume to the design rainfall events using the PCSWMM. The results indicated that, overall, CC has a greater impact on the runoff attributes than LULC change. We also found that LULC and climate induced changes in runoff are generally more pronounced in greater recurrence intervals and subwatersheds with smaller drainage areas and milder slopes. However, no relationship was found between the changes in runoff and original subwatershed imperviousness; this can be due to the small increase in urban land cover projected for the study area. This research helps urban planners and floodplain managers identify the required strategies to protect urban watersheds against future LULC change and CC. [Display omitted] • Changes in runoff attributes due to CC and LULC change in 3800 urban watersheds. • Greater changes for runoff peak than volume. • Greater changes in both runoff attributes for milder slope and smaller watersheds. • Dominant impacts of CC over LULC change for both runoff attribute. [ABSTRACT FROM AUTHOR]

Abstract High resolution hydrodynamic models are computationally expensive to run – especially if ensemble forecasts are desired. This can be problematic within coastal estuaries which are not well resolved by today's operational meteorological forecast models. As an alternative, this paper evaluates the wind forcing for three setup parameterizations (based on the Zuiderzee, modified Zuiderzee, and long wave equations) using a combination of observed setup from in-situ water level gauges and local wind observations. In addition, three methods are explored for developing hourly time series of wind forcing from 5-min observations: top of the hour, hourly mean, and wind run approach. The wind forcings, which are weighted by the length of two lagoon-oriented axes, are used to drive the setup parameterizations. The observed setup is used to tune each of the parameterizations via a least squares approach. The observation spread, linear model residuals, coefficient of determination (R2), and root mean squared error (RMSE) indicate that the wind run out performs the other two methods. In terms of the three parameterizations, the modified Zuiderzee had consistently higher R2 values, lower RMSE, and narrower 95% confidence intervals than the two other methods. This optimized parameterization is currently being used operationally to generate ensemble setup forecasts for the Indian River Lagoon, a restricted estuary on Florida's east-central coast. These simple ensemble forecasts are designed to guide the National Weather Service (NWS) in identifying potentially significant setup events that warrant high resolution hydrodynamic simulations. [ABSTRACT FROM AUTHOR]

Uninformed buyers may pay more when purchasing complex assets, such as houses. This paper compares local house buyers who are later foreclosed with those not foreclosed for various buyer-types, namely, owner-occupier households, investor-companies, second-home buyers, and small-scale investors. Data from one of the foreclosure epicenters, Orange County, Florida, reveal that subsequent foreclosures are associated with higher prices for comparable housing at the time of purchase. The premium paid by buyers between 2000 and 2007 who experience foreclosure after 2007 is larger closer to the 2007 market peak, approaching 3 percent. We find considerable heterogeneity across buyer-types. In particular, foreclosed second-home buyers and small-scale investors systematically pay more, while investor-companies and owner-occupiers do not. The pattern is consistent with the hypothesis that the premium paid by foreclosed households reflects poor information or limited financial acumen. • This paper compares buyers who are later foreclosed with those not foreclosed. • Buyer include investor-companies, owner-occupiers, second-home buyers, and small-scale investors. • Data cover one of the foreclosure epicenters, Orange County, Florida. • We find that buyers who experience foreclosure after 2007 pay more for comparable housing. • We find considerable heterogeneity across buyer-types. [ABSTRACT FROM AUTHOR]

Research on college dropout has largely addressed early exit from school, even though a large share of students who do not earn degrees leave after their second year. In this paper, we offer new evidence on the scope of college late departure. Using administrative data from Florida and Ohio, we conduct an event history analysis of the dropout process as a function of credit attainment. Our results indicate that late departure is widespread, particularly at two- and open-admission four-year institutions. We estimate that 14 percent of all entrants to college and one-third of all dropouts completed at least three-quarters of the credits that are typically required to graduate before leaving without a degree. Our results also indicate that the probability of departure spikes as students near the finish line. Amidst considerable policy attention towards improving student outcomes in college, our findings point to promising new avenues for intervention to increase postsecondary attainment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thrips chose flush foliage over reproductive tissues. • In the absence of flush foliage, thrips chose reproductive tissues. • Thrips directly damage host reproductive tissues and survive to adulthood. • Tissues differed in their volatile constituents. The biological control agent, Pseudophilothrips ichini, is being released for control of Brazilian peppertree, Schinus terebinthifolia (Anacardiaceae), an invasive weed of natural and agricultural areas of California, Florida, Hawaii, and Texas (USA). The thrips larvae and adults feed on flushed leaves and stems that are produced during the vegetative season of the host. However, during the reproductive season from September to December in Florida, few flushing leaves are available as resources are shunted to plant reproduction. As field releases were being implemented, thrips were found feeding and damaging immature fruits and flowers of their host. We hypothesized that the thrips used volatile organic compounds produced by reproductive tissues to locate and feed on these tissues. When examined under laboratory choice tests, individual thrips or groups of either 20 adults or larvae, chose flushing leaves over all reproductive tissues, female flowers, male flowers, and immature fruit. However, to simulate seasons when few flushing leaves were available, additional choice tests were conducted where flushing leaves were omitted, and only reproductive tissues and a filter paper control were included. Individual thrips or groups of either 20 adults or larvae selected all reproductive tissues over controls. When presented with a choice between immature and mature fruit, thrips chose immature fruit. Thrips caused significant damage to live female flowers, male flowers, and immature fruit, and thrips survival rates were similar when fed flush leaves, female flowers, or male flowers. The thrips responses could be tied to VOC production, which significantly varied among tissue types. Volatile blends from flush leaves that include DMNT, Terpinolene, and δ-Elemene may attract P. ichini whereas those that repel them include α-Thujene, α-Pinene, β-Pinene, Camphene, and β-Phellandrene. These results suggest P. ichini has a flexible feeding strategy and exploits Brazilian peppertree reproductive tissues when few flushing tips were available. Further they suggest thrips feeding will have direct impacts on Brazilian peppertree reproduction. [ABSTRACT FROM AUTHOR]

This paper studies the impact of hurricanes on housing markets and population turnover using microdata from Florida during 2000–2016. We find that hurricanes cause a temporary increase in home prices and a concurrent decrease in transactions, which together imply a negative transitory shock to the housing supply. Using mortgage application data, we find that incoming homeowners in this period have higher incomes, leading to an overall shift toward wealthier groups. Our findings suggest that market responses to natural disasters can lead to uneven and lasting demographic changes in affected communities, even with a full recovery in physical capital. [ABSTRACT FROM AUTHOR]

Many coastal urban areas are experiencing impacts of accelerated chronic and episodic flooding on the built environment and people's livelihoods and quality of life. These impacts sometimes exceed the households' adaptive and coping capacities to deal with flooding, prompting residents to consider relocation. It is unclear how urban dwellers living in flood-prone locations perceive this adaptation strategy and under what flood-driven circumstances they would consider permanently moving. This paper provides empirical evidence on relocation preferences among urban residents along the U.S. East Coast. It further explores how this decision is influenced by socioeconomic determinants, experiences with flood exposure, comprehensive concerns with flooding, and preferences for relocation destinations. We administered an online survey to 1450 residents living in flood-prone urban areas across multiple states, from New York to Florida, and analyzed the results using descriptive and inferential statistics. Results show that almost half of respondents would consider relocating due to coastal flooding, with only 13 percent declining this option. The results show that age and race, several determinants of place attachment, problem-solving capacity, and flood-related household- and community-level concerns play a significant role in willingness to relocate. • Accelerated flooding in coastal urban areas will increase the need for relocation. • Empirical evidence about coastal relocation drivers is limited. • Survey responses indicate that many urban coastal residents are willing to relocate. • Willingness to relocate is affected by age and race, and other personal concerns. • Crime, future flooding, community support, and living costs predict relocation. [ABSTRACT FROM AUTHOR]

This paper develops and solves a spatiotemporal equilibrium model in which regional wages and house prices are jointly determined with location-to-location migration flows. The agent's optimal location choice and the resultant migration process are shown to be Markovian, with the transition probabilities across all location pairs given as non-linear functions of wage and housing cost differentials, endogenously responding to migration flows. The model can be used for the analysis of spatial distribution of population, income, and house prices, as well as for spatiotemporal impulse response analysis. The model is estimated on a panel of 48 mainland U.S. states and the District of Columbia using the training sample (1976–1999), and shown to fit the data well over the evaluation sample (2000–2014). The estimated model is then used to analyze the size and speed of spatial spill-over effects by computing spatiotemporal impulse responses of positive productivity and land-supply shocks to California, Texas, and Florida. Our simulation results show that states with a lower level of land-use regulation can benefit more from positive state-specific productivity shocks; and positive land-supply shocks are much more effective in states, such as California, that are subject to more stringent land-use regulations. • We propose a spatiotemporal equilibrium model of the housing market. • The dynamics of location-to-location migration flows are explicitly modeled. • The estimated model is used to analyze the size and speed of spatial spill-over effects. • States with less land-use regulation benefit more from positive productivity shocks. • Land-supply shocks are more effective in states with stringent land-use regulations. [ABSTRACT FROM AUTHOR]

Abstract: This paper assesses the impact of European ceramics on preexisting American potting technologies. Specifically we investigate the technological features of pigments used for production of colonial American majolica. In order to achieve this goal, majolica sherds from Puebla (4), and Oaxaca (2), both in Mexico, from Antigua (Guatemala) (2), from Panama (1), and from Mission San Luis (Florida) (5) were analyzed by synchrotron micro-X-ray diffraction (μ-XRD). Eleven out of these fourteen samples were also analyzed by scanning electron microscopy (SEM). The combination of micro-chemical and micro-structural techniques provides a cross sectional profile of the constituent minerals present ultimately providing information about the nature and distribution of the pigments used in their decorations, their dissolution in the glassy matrix, and the formation of crystalline compounds. Our results reveal significant differences among productions. [Copyright &y& Elsevier]

One of the most commonly employed water conservation strategies is to restrict lawn watering to limited times on specified days. Water managers typically assume that limiting the frequency and duration of lawn watering will reduce water use. Consequently, the effectiveness of water restrictions is often evaluated based on observed compliance to the specified schedule, whether or not actual reductions in water use are achieved. This assessment approach is more practical than quantifying the reduction in water use brought about by restrictions because quantification of lawn water use is hampered by difficulties in disaggregating the various components of residential water use. Dual meters to separately meter the portion of public supply devoted to lawn water use are rare, and for households that withdraw water from private wells, canals, or ponds for lawn watering, there is no record of such water use at all. As a consequence of this gap in water use data, compliance to a prescribed frequency of watering is often equated with effectiveness. In this paper we develop an alternative metric for evaluating the effectiveness of water restrictions and present a case study in a suburban area in Southeast Florida that illustrates some of the challenges of quantifying lawn water use and explores some of the limitations of day of the week water restrictions as a conservation strategy. [Copyright &y& Elsevier]

Abstract: This paper presents an application of a three-dimensional unstructured Cartesian grid model (Chen, 2011) to a real-world case, namely the Crystal River/Kings Bay system located on the Gulf coast of the Florida peninsula of the United States. Crystal River/Kings Bay is a spring-fed estuarine system which is believed to be the largest natural refuge in the United States for manatees during the coldest days in winter because of the existence of a large amount of discharge out of numerous spring vents at the bottom of Kings Bay. The unstructured Cartesian grid model was used to simulate hydrodynamics, including salinity transport processes and thermodynamics, in the estuary during a 34-month period from April 2007 to February 2010. Although there are some unidentified uncertainties in quantifying flow rates from the spring vents and salinity variations in spring flows, simulated water elevations, salinities, temperatures, and cross-sectional flux all match well or very well with measured real-time field data. This suggests that the unstructured Cartesian grid model can adequately simulate hydrodynamics in a complex shallow water system such as Crystal River/Kings Bay and the numerical theory for the unstructured Cartesian grid model works properly. The successful simulation of hydrodynamics in the estuarine system also suggests that an empirical formula that relates the spring discharge with the water level in Kings Bay and the groundwater level measured in a nearby well is reasonable. [Copyright &y& Elsevier]

Abstract: The promulgation of numeric nutrient criteria for evaluating impairment of waterbodies in Florida is underway. Adherence to the water quality standards needed to meet these criteria will potentially require substantial allocations of public and private resources in order to better control nutrient (i.e., nitrogen and phosphorus) releases from contributing sources. Major sources of nutrients include atmospheric deposition (195–380 mg-N/m2/yr, 6 to 16 mg-P/m2/yr), reclaimed water irrigation (0.13–29 mg-N/L, 0.02 to 6 mg-P/L), septic systems (3.3 × 103–6.68 × 103 g-N/person/yr, 0.49 × 103–0.85 × 103 g-P/person/yr) and fertilizer applications (8 × 106–24 × 106 mg-N/m2/yr). Estimated nitrogen loadings to the Florida environment, as calculated from the above rates are as follows: 5.9 × 109–9.4 × 109 g-N/yr from atmospheric deposition, 1.2 × 108–2.6 × 1010 g-N/yr from reclaimed water, 2.4 × 1010–4.9 × 1010 g-N/year from septic systems, and 1.4 × 1011 g-N/yr from fertilizer application. Similarly, source specific phosphorus loading calculations are also presented in this paper. A fraction of those nutrient inputs may reach receiving waterbodies depending upon site specific regulation on nutrient control, nutrient management practices, and environmental attenuation. In Florida, the interconnectivity of hydrologic pathways due to the karst landscape and high volumes of rainfall add to the complexity of tracking nutrient loads back to their sources. In addition to source specific nutrient loadings, this review discusses the merits of source specific markers such as elemental isotopes (boron, nitrogen, oxygen, strontium, uranium and carbon) and trace organic compounds (sucralose, gadolinium anomaly, carbamazepine, and galaxolide) in relating nutrient loads back to sources of origin. Although this review is focused in Florida, the development of source specific markers as a tool for tracing nutrient loadings back to sources of origin is applicable and of value to all other geographical locations. [Copyright &y& Elsevier]

Abstract: This paper presents a sensitivity study of simulated availability of low salinity habitats by a hydrodynamic model for the Manatee River estuary located in the southwest portion of the Florida peninsula. The purpose of the modeling study was to establish a regulatory minimum freshwater flow rate required to prevent the estuarine ecosystem from significant harm. The model used in the study was a multi-block model that dynamically couples a three-dimensional (3D) hydrodynamic model with a laterally averaged (2DV) hydrodynamic model. The model was calibrated and verified against measured real-time data of surface elevation and salinity at five stations during March 2005–July 2006. The calibrated model was then used to conduct a series of scenario runs to investigate effects of the flow reduction on salinity distributions in the Manatee River estuary. Based on simulated salinity distribution in the estuary, water volumes, bottom areas and shoreline lengths for salinity less than certain predefined values were calculated and analyzed to help establish the minimum freshwater flow rate for the estuarine system. The sensitivity analysis conducted during the modeling study for the Manatee River estuary examined effects of the bottom roughness, ambient vertical eddy viscosity/diffusivity, horizontal eddy viscosity/diffusivity, and ungauged flow on the model results and identified the relative importance of these model parameters (input data) to the outcome of the availability of low salinity habitats. It is found that the ambient vertical eddy viscosity/diffusivity is the most influential factor controlling the model outcome, while the horizontal eddy viscosity/diffusivity is the least influential one. [Copyright &y& Elsevier]

Exploring the quantitative association between landscape characteristics and the ecological conditions of receiving waters has recently become an emerging area for eco-environmental research. While the landscape–water relationship research has largely targeted on inland aquatic systems, there has been an increasing need to develop methods and techniques that can better work with coastal and estuarine ecosystems. In this paper, we present a geospatial approach to examine the quantitative relationship between landscape characteristics and estuarine nitrogen loading in an urban watershed. The case study site is in the Pensacola estuarine drainage area, home of the city of Pensacola, Florida, USA, where vigorous urban sprawling has prompted growing concerns on the estuarine ecological health. Central to this research is a remote sensor image that has been used to extract land use/cover information and derive landscape metrics. Several significant landscape metrics are selected and spatially linked with the nitrogen loading data for the Pensacola bay area. Landscape metrics and nitrogen loading are summarized by equal overland flow-length rings, and their association is examined by using multivariate statistical analysis. And a stepwise model-building protocol is used for regression designs to help identify significant variables that can explain much of the variance in the nitrogen loading dataset. It is found that using landscape composition or spatial configuration alone can explain most of the nitrogen loading variability. Of all the regression models using metrics derived from a single land use/cover class as the independent variables, the one from the low density urban gives the highest adjusted R-square score, suggesting the impact of the watershed-wide urban sprawl upon this sensitive estuarine ecosystem. Measures towards the reduction of non-point source pollution from urban development are necessary in the area to protect the Pensacola bay ecosystem and its ecosystem services. [Copyright &y& Elsevier]

Abstract: Hypoxia has occurred in Upper Charlotte Harbor, a shallow (∼3 m) estuary in Southwest Florida, during moderate to high freshwater flows from the Peace and Myakka Rivers and after hurricanes, due to nutrient loading and vertical stratification. This paper studies the annual hypoxia and water quality dynamics in Upper Charlotte Harbor in 2000, using CH3D-IMS, an integrated modeling system which includes coupled models of circulation, wave, sediment transport, and water quality. The CH3D-IMS simulations showed that bottom-water hypoxic conditions occur during periods with relatively steady moderate to high (5–40 m3/s) freshwater inflows and sediment oxygen demand (SOD). During periods of relatively steady moderate to high river discharge, strong vertical salinity stratification results in reduced vertical mixing which prevents surface water from supplying dissolved oxygen (DO) to bottom water where SOD continuously consumes DO. There was significant temporal fluctuation of the hypoxic water volume, as a result of significant temporal variation in vertical turbulent mixing associated with combinations of spring-neap tides and river discharge. The validated modeling system could be used to forecast hypoxia. [ABSTRACT FROM AUTHOR]

Global climate change will influence environmental conditions including temperature, surface radiation, soil moisture, and sea level, and it will also significantly impact regional-scale hydrologic processes such as evapotranspiration (ET), precipitation, runoff, and snowmelt. The quantity and quality of water available for drinking and other domestic usage is also likely to be affected by changes in these processes. Consequently, it is necessary to assess and reflect upon the challenges ahead for water infrastructure and the general public in metropolitan regions. One approach to the problem is to use index-based assessment, forecasting and planning. The drought indices previously developed were not developed for domestic water supplies, and thus are insufficient for the purpose of such an assessment. This paper aims to propose and develop a “Metropolitan Water Availability Index (MWAI)” to assess the status of both the quantity and quality of available potable water sources diverted from the hydrologic cycle in a metropolitan region. In this approach, the accessible water may be expressed as volume per month or week (i.e., m3/month or m3/week) relative to a prescribed historical record, and such a trend analysis may result in final MWAI values ranging from −1 to +1 for regional water management decision making. The MWAI computation uses data and information from both historical point measurements and spatial remote-sensing based monitoring. Variables such as precipitation, river discharge, and water quality changes at drinking water plant intakes at specific locations are past “point” measurements in MWAI calculations. On the other hand, remote sensing provides information on both spatial and temporal distributions of key variables. Examples of remote-sensing images and sensor network technologies are in-situ sensor networks, ground-based radar, air-borne aircraft, and even space-borne satellites. A case study in Tampa Bay, Florida is described to demonstrate the short-term assessment of the MWAI concept at a practical level. It is anticipated that such a forecasting methodology may be extended for middle-term and long-term water supply assessment. [Copyright &y& Elsevier]

Abstract: This paper presents an integrated hydrodynamic modeling and probability analysis approach to assess the long-term effects of changing river inflows on the estuarine ecosystem. The probability analysis method, which is popularly used in advanced hydrological frequency analysis of river flows and rainfalls, has been applied to analyze the effects of changing inflow on salinity and thus on oyster ecology in Apalachicola Bay. Long-term salinity data were predicted through the application of a calibrated 3D hydrodynamic model under two river inflow conditions over a 10-year period. The first flow represents the historic flow. The 2nd flow condition, called Scenario-1, represents a regulated flow scenario to account for the potential increasing upstream water demands. Two stations, Mid Bay and Dry Bar, in the bay were selected to examine the estuarine responses. Under the historic flow condition, the maximum probability salinity at Dry Bar in the rich oyster reef is near 24ppt, within the optimal salinity range for oyster growth of 16–26 ppt (Harned et al., 1996); the maximum probability salinity at Mid Bay station is 27ppt, beyond the optimal salinity for oyster growth in mid-bay area where there is no oyster reef around. While it is difficult to examine the difference between two scenarios by conventional time series analysis of river flows and salinity, probability analysis reasonably characterizes and quantifies the changes of river flow and salinity patterns over the 10-year period. The Scenario-1 has caused the increase of the probability in low flows. Higher probability of low flows for the regulated flow scenario shortens the period of optimal salinity in the oyster reef, and cause substantial increase of exceedance probability of higher salinity in the oyster reef to the level beyond the optimal salinity range for oyster growth. The probability analysis approach has demonstrated its advantage for the risk assessments of the long-term estuarine ecohydrological effects under various regulated inflow scenarios to support estuarine water resources managements. [Copyright &y& Elsevier]

• Since the Great Recession, single-family rentals have increased as a share of the housing units within America's neighborhoods. • Homeowners are concerned that single-family rentals will lower their neighborhood's quality and have an adverse effect on their property values. • Results show that an increase in single-family rentals as a share of a neighborhood's housing units lower house values. • The negative effects of single-family rentals on a neighborhood's house values vary by type of rental and neighborhood. • Estimated models control for the endogeneity of single-family rentals and sample selection. Since the Great Recession, single-family rentals have increased as a share of the housing units within America's neighborhoods. Homeowners are concerned that this shift in housing tenure will lower their neighborhood's quality and have an adverse effect on their property values. However, no current evidence exists on whether these concerns have any validity. In this paper, we utilize a six-year balanced panel of neighborhoods from the state of Florida's metropolitan areas to study the impacts that single-family rentals have on the values of single-family homes. Our case for causality is buttressed by estimating house value models that include time and neighborhood fixed effects, treat the rentals as endogenous variables, and control for sample selection and changes in neighborhood demographics and land uses. Our results show that share increases in single-family rentals lower house values, but the effects vary between central cities and suburbs, across neighborhoods of different income levels and density, by the price of the rental unit, and whether the owner has a mailing address outside the state of Florida. [ABSTRACT FROM AUTHOR]

Some socioeconomically vulnerable groups may experience disproportionately higher risk of extreme heat illness than other groups, but no study has utilized the presence/absence of a social security number (SSN) as a proxy for vulnerable sub-populations. This study focused on the warm season from 2008 to 2012 in Florida, U.S. With a total number of 8,256,171 individual level health outcomes, we devised separate case-crossover models for five heat-sensitive health outcomes (cardiovascular disease, dehydration, heat-related illness, renal disease, and respiratory disease), type of health care visit (emergency department (ED) and hospitalization), and patients reporting/not reporting an SSN. Each stratified model also considered potential effect modification by sex, age, or race/ethnicity. Mean temperature raised the odds of five heat-sensitive health outcomes with the highest odds ratios (ORs) for heat-related illness. Sex significantly modified heat exposure effects for dehydration ED visits (Males: 1.145, 95 % CI: 1.137–1.153; Females: 1.110, 95 % CI: 1.103–1.117) and hospitalization (Males: 1.116, 95 % CI: 1.110–1.121; Females: 1.100, 95 % CI: 1.095–1.105). Patients not reporting an SSN between 25 and 44 years (1.264, 95 % CI: 1.192–1.340) exhibited significantly higher dehydration ED ORs than those reporting an SSN (1.146, 95 % CI: 1.136–1.157). We also observed significantly higher ORs for cardiovascular disease hospitalization from the no SSN group (SSN: 1.089, 95 % CI: 1.088–1.090; no SSN: 1.100, 95 % CI: 1.091–1.110). This paper partially supports the idea that individuals without an SSN could experience higher risks of dehydration (for those 25–45 years), renal disease, and cardiovascular disease than those with an SSN. • The first study with more than 8 million heat-related health outcomes in Florida. • Social security number was used to detect subpopulations vulnerable to extreme heat. • Sex significantly modified heat exposure effects for dehydration health outcomes. • No SSN group had higher risks of dehydration, renal, and cardiovascular disease. [ABSTRACT FROM AUTHOR]

Abstract: Freshwater fraction method is popular for cost-effective estimations of estuarine flushing time in response to freshwater inputs. However, due to the spatial variations of salinity, it is usually expensive to directly estimate the long-term freshwater fraction in the estuary from field observations. This paper presents the application of the 3D hydrodynamic model to estimate the distributions of salinity and thus the freshwater fractions for flushing time estimation. For a case study in a small estuary of the North Bay in Florida, USA, the hydrodynamic model was calibrated and verified using available field observations. Freshwater fractions in the estuary were determined by integrating freshwater fractions in model grids for the calculation of flushing time. The flushing time in the North Bay is calculated by the volume of freshwater fraction divided by the freshwater inflow, which is about 2.2days under averaged flow conditions. Based on model simulations for a time series of freshwater inputs over a 2-year period, a power regression equation has been derived from model simulations to correlate estuarine flushing time to freshwater inputs. For freshwater input varying from 12m3/s to 50m3/s, flushing time in this small estuary of North Bay changes from 3.7days to 1.8days. In supporting estuarine management, the model can be used to examine the effects of upstream freshwater withdraw on estuarine salinity and flushing time. [Copyright &y& Elsevier]

Abstract: The relationship often assumed by environmental justice researchers is that proximity to a hazardous waste site is a measure of exposure to harmful chemicals. Few researchers, however, explicitly address the methodological challenge of measuring the causal relationship between toxic chemical exposure and health problems. To better understand the methodological task of moving beyond the proximity-exposure assumption, the three most commonly used quantitative methodological approaches in environmental justice research are briefly outlined. Using geographic information system techniques, we operationalize toxic exposure as an interval-level variable and integrate this data with geocoded health and social survey information. We develop a methodological design that enables researchers to assess what factors cause mental and physical health problems for individuals living in contaminated areas. The results of the hierarchical multiple regression analyses indicate that sociodemographic, perceived exposure, objective exposure, and food consumption variables are significant predictors of physical health and psychological well-being. We also found a significant relationship between physical health and psychological well-being. The data used in this paper were collected in a low-income, African-American community in Fort Lauderdale, Florida. This community is contiguous to a Superfund site (EPA) called the Wingate Road Municipal Incinerator and Landfill. [Copyright &y& Elsevier]

Abstract: This paper uses one of the strongest hurricanes to hit the US, Andrew in 1992, to define a quasi-random experiment that permits estimation of the responses of housing values to information about new hurricanes. Lee County, Florida did not experience damage from Andrew. The storm was a “near-miss.” We hypothesize that Andrew conveyed risk information to homeowners in the county. A difference-in-differences (DND) framework identifies the effect of this information on property values in areas likely to experience significant storm damage. The DND findings indicate at least a 19 percent decline in property values. [Copyright &y& Elsevier]

Salinity is an important factor for oyster and estuarine productivity in Apalachicola Bay. Observations of salinity at oyster reefs have indicated a high correlation between subtidal salinity variations and the surface winds along the bay axis in an approximately east–west direction. In this paper, we applied a calibrated hydrodynamic model to examine the surface wind effects on the volume fluxes in the tidal inlets and the subtidal salinity variations in the bay. Model simulations show that, due to the large size of inlets located at the east and west ends of this long estuary, surface winds have significant effects on the volume fluxes in the estuary inlets for the water exchanges between the estuary and ocean. In general, eastward winds cause the inflow from the inlets at the western end and the outflow from inlets at the eastern end of the bay. Winds at 15 mph speed in the east–west direction can induce a 2000 m3 s−1 inflow of saline seawater into the bay from the inlets, a rate which is about 2·6 times that of the annual average freshwater inflow from the river. Due to the varied wind-induced volume fluxes in the inlets and the circulation in the bay, the time series of subtidal salinity at oyster reefs considerably increases during strong east–west wind conditions in comparison to salinity during windless conditions. In order to have a better understanding of the characteristics of the wind-induced subtidal circulation and salinity variations, the researchers also connected model simulations under constant east–west wind conditions. Results show that the volume fluxes are linearly proportional to the east–west wind stresses. Spatial distributions of daily average salinity and currents clearly show the significant effects of winds on the bay. [Copyright &y& Elsevier]

Environmental regulators often use dynamic enforcement, which bases penalties and enforcement effort on plants' past compliance history, to improve compliance and decrease emissions when enforcement resources are limited. Using plant-level data from the Environmental Protection Agency (EPA), I examine an unexpected shift in the use of traditional enforcement by environmental regulators in Florida, showing that all of the state's plants decreased emissions and improved compliance following an increase in penalties for those with Priority Violations. The largest improvements were observed among plants with the highest expected costs of compliance, which is consistent with the theory of dynamic enforcement. These results are robust to the use of control plants from nearby southern states, as well as control plants selected via a matching algorithm. The paper's findings (1) provide quasi-experimental evidence on the effectiveness of traditional enforcement actions, and (2) suggest that dynamic incentives may matter for plant compliance decisions. [ABSTRACT FROM AUTHOR]