Future impacts of fresh water resource management: sensitivity of coastal deltas

We present an assessment of contemporary and future effective sealevel rise (ESLR) using a sample of 40 deltas distributed worldwide. For any delta, ESLR is a net rate defined by eustatic sea-level rise, natural gross rates of fluvial sediment deposition and subsidence, and accelerated subsidence due to groundwater and hydrocarbon extraction. Present-day ESLR, estimated from geospatial data and a simple model of deltaic dynamics, ranges from 0.5 to 12.5 mm year-1. Reduced accretion of fluvial sediment from upstream siltation of reservoirs and freshwater consumptive irrigation losses are primary determinants of ESLR in nearly 70% of the deltas, while for only 12% eustatic sea-level rise predominates. Future scenarios indicate a much larger impact on deltas than previously estimated. Serious challenges to human occupancy of deltas worldwide are conveyed by upland watershed factors, which have been studied less comprehensively than the climate change and sea-level rise question

Suicide risk in schizophrenia: learning from the past to change the future

Suicide is a major cause of death among patients with schizophrenia. Research indicates that at least 5–13% of schizophrenic patients die by suicide, and it is likely that the higher end of range is the most accurate estimate. There is almost total agreement that the schizophrenic patient who is more likely to commit suicide is young, male, white and never married, with good premorbid function, post-psychotic depression and a history of substance abuse and suicide attempts. Hopelessness, social isolation, hospitalization, deteriorating health after a high level of premorbid functioning, recent loss or rejection, limited external support, and family stress or instability are risk factors for suicide in patients with schizophrenia. Suicidal schizophrenics usually fear further mental deterioration, and they experience either excessive treatment dependence or loss of faith in treatment. Awareness of illness has been reported as a major issue among suicidal schizophrenic patients, yet some researchers argue that insight into the illness does not increase suicide risk. Protective factors play also an important role in assessing suicide risk and should also be carefully evaluated. The neurobiological perspective offers a new approach for understanding self-destructive behavior among patients with schizophrenia and may improve the accuracy of screening schizophrenics for suicide. Although, there is general consensus on the risk factors, accurate knowledge as well as early recognition of patients at risk is still lacking in everyday clinical practice. Better knowledge may help clinicians and caretakers to implement preventive measures. This review paper is the results of a joint effort between researchers in the field of suicide in schizophrenia. Each expert provided a brief essay on one specific aspect of the problem. This is the first attempt to present a consensus report as well as the development of a set of guidelines for reducing suicide risk among schizophenia patients

Climate Change and Water Resources in New England

Hydrology is embedded in climate. The water potentially available for human use and management, Q, is determined as the difference between long-term average precipitation, P, and evapotranspiration, E: Q = P_E. 23 = 41_18 inches/yr (New England averages). P is obviously a central component of climate, and E is largely determined by climatic factors, especially temperature, humidity, wind, and the timing of precipitation inputs. The presentation will include a review of recent literature leading to an assessment of predicted and observed changes in aspects of New England hydroclimate as a result of projected global climate change. New England has experienced severe droughts approximately once per decade since the late 1800s, the most severe and extensive of which was the drought of the 1960s. This drought and monthly and winter streamflows generally are correlated with the North Atlantic Oscillation (NAO), especially at decadal scales; but there is no correlation between NAO and precipitation. Winter streamflows are correlated with the Pacific North American pattern (PNA). There is no consistent correlation of New England hydroclimate and the El Nino-Southern Oscillation phenomenon. Human population growth in New England has been accompanied by activities that have strong effects on the region’s hydrology, including landcover changes (afforestation-deforestation, urbanization), inter-basin transfers of water (especially the Boston system), construction of dams, and withdrawals from surface and ground water. In general, these non-climatic factors are more profound and predictable than those that may accompany anthropogenically-induced climate change, at least in the short- to medium-term. Support of government programs that monitor hydroclimate, especially those of NOAA and the U.S. Geological Survey, is essential for understanding and responding to non-climatic and climatic changes that affect the region’s water resources

Effective sea-level rise in deltas: Causes of change and human dimension implications

An assessment is made of contemporary effective sea-level rise (ESLR) for a sample of 40 deltas distributed worldwide. For any delta, ESLR is a net rate, defined by the combination of eustatic sea-level rise, the natural gross rate of fluvial sediment deposition and subsidence, and accelerated subsidence due to groundwater and hydrocarbon extraction. ESLR is estimated under present conditions using a digital data set of delta boundaries and a simple model of delta dynamics. The deltas in this study represent all major climate zones, levels of population density, and degrees of economic development. Collectively, the sampled deltas serve as the endpoint for river basins draining 30% of the Earth\u27s landmass, and 42% of global terrestrial runoff. Nearly 300 million people inhabit these deltas. For the contemporary baseline, ESLR estimates range from 0.5 to 12.5 mm yr− 1. Decreased accretion of fluvial sediment resulting from upstream siltation of artificial impoundments and consumptive losses of runoff from irrigation are the primary determinants of ESLR in nearly 70% of the deltas. Approximately 20% of the deltas show accelerated subsidence, while only 12% show eustatic sea-level rise as the predominant effect. Extrapolating contemporary rates of ESLR through 2050 reveals that 8.7 million people and 28,000 km2 of deltaic area in the sample set of deltas could suffer from enhanced inundation and increased coastal erosion. The population and area inundated rise significantly when considering increased flood risk due to storm surge. This study finds that direct anthropogenic effects determine ESLR in the majority of deltas studied, with a relatively less important role for eustatic sea-level rise. Serious challenges to human occupancy of deltaic regions worldwide are thus conveyed by factors which to date have been studied less comprehensively than the climate change–sea-level rise question

Evaluating the potential for measuring river discharge from space

Numerous studies have demonstrated the potential usefulness of river hydraulic data obtained from satellites in developing general approaches to tracking floods and changes in river discharge from space. Few studies, however, have attempted to estimate the magnitude of discharge in rivers entirely from remotely obtained information. The present study uses multiple-regression analyses of hydraulic data from more than 1000 discharge measurements, ranging in magnitude from over 200,000 to less than 1 m3/s, to develop multi-variate river discharge estimating equations that use various combinations of potentially observable variables to estimate river discharge. Uncertainty analysis indicates that existing satellite-based sensors can measure water-surface width (or surface area), water-surface elevation, and potentially the surface velocity of rivers with accuracies sufficient to provide estimates of discharge with average uncertainty of less than 20%. Development and validation of multi-variate rating equations that are applicable to the full range of rivers that can be observed from satellite sensors, development of techniques to accurately estimate the average depth in rivers from stage measurements, and development of techniques to accurately estimate the average velocity in rivers from surface-velocity measurements will be key to successful prediction of discharge from satellite observations