Assessing river flood risk and adaptation in Europe—review of projections for the future

Flood damages have exhibited a rapid upward trend, both globally and in Europe, faster than population and economic growth. Hence, vigorous attempts of attribution of changes have been made. Flood risk and vulnerability tend to change over many areas, due to a range of climatic and nonclimatic impacts whose relative importance is site-specific. Flooding is a complex phenomenon and there are several generating mechanisms, among others intense and/or long-lasting precipitation, snowmelt, ice jam. Projected climate-driven changes in future flood frequency are complex, depending on the generating mechanism, e.g., increasing flood magnitudes where floods result of heavy rainfall and possibly decreasing magnitudes where floods are generated by spring snowmelt. Climate change is likely to cause an increase of the risk of riverine flooding across much of Europe. Projections of flood hazard in Europe based on climatic and hydrological models, reviewed in this paper, illustrate possible changes of recurrence of a 100-year flood (with probability of exceedance being 1-in-100 years) in Europe. What used to be a 100-year flood in the control period is projected to become either more frequent or less frequent in the future time horizon of concern. For a large part of the continent, large flooding is projected to become more commonplace in future, warmer climate. Due to the large uncertainty of climate projections, it is currently not possible to devise a scientifically-sound procedure for redefining design floods (e.g. 100-year flood) in order to adjust flood defenses. For the time being, we recommend to adjust design floods using a “climate change factor” approach.     

Evaluation of innovative municipal solid waste management through urban symbiosis: a case study of Kawasaki

Industrial symbiosis encourages the establishment of a broad eco-industrial network so that more synergy opportunities can be identified. By linking municipal solid waste management (MSWM) with local industries, i.e., urban symbiosis, new symbiotic opportunities can be generated from the geographic proximity of urban and industrial areas, transferring physical resources from urban refuse directly to industrial applications and improving the overall eco-efficiency of the city as a whole. Using a case study of Kawasaki, this paper simulates and evaluates an innovative waste management initiative in Kawasaki by an scenario simulation model based on the LCA approach. Results show that recycling mixed paper, mixed plastics, and organic wastes and utilizing the recycled materials in industrial production will potentially reduce about 69 kt CO₂(e) emissions and 8 kt incineration ashes to be landfilled in 2015. To achieve these outcomes, the total additional cost compared with the current practice is about 1.2 billion JPY.     

Pigments of meso- and bathypelagic chaetognaths

Pigments of the meso- and bathypelagic chaetognaths Sagitta macrocephala and Eukrohnia fowleri were studied by chromatographic analysis. Supplementary histological studies were also performed. Fat-soluble properties and absorption spectra of the chaetognath pigments indicated that all pigments were carotenoid, independent of chaetognath species or habitat. The major carotenoid in chaetognaths was very soluble in nonpolar solvents such as carotenes, although its absorption spectrum formed a single broad peak at around 460 nm. The characteristics of the carotenoids in the chaetognaths were different from those of the pigments in the plankton which formed their diet. It is therefore inferred that carotenoids in chaetognaths are not formed by the deposition of food pigments in the intestinal tissue, but are synthesized by the chaetognaths themselves.     

Sanitation of seawater effluent from seaweed processing plants using a photo-catalytic TiO2 oxidation

A fine porcelain open-cell photo-catalytic filter with titanium dioxide (TiO(2)) was evaluated for sterilization and sanitation of bio-polluted industrial water. In simulated seawater industrial effluent samples, the populations of Escherichia coli and Vibrio parahaemolyticus quickly decreased and reached non-detectable level within 10min. In seawater effluents from a seaweed processing plant, the bacterial populations in two samples quickly decreased by more than 10(3). In another two samples the decreases were slow and lowered by less than 10(2). Using fluorescence microscopy, it was indicated that the bacterial cells treated with photo-catalytic TiO(2) were damaged. In addition, the protein concentration in simulated seawater effluent slowly decreased using the photo-catalytic TiO(2) reaction; and reached similar concentrations as seawater near cultured seaweed beds. These results indicate that using a reactor with a TiO(2) photo-catalyst filter was effective for the sanitation of seawater effluents.     

Relationship between traffic fatalities and drunk driving in Japan

OBJECTIVE: The present study was performed to clarify the relation between alcohol use and traffic fatalities in accidents involving motor vehicles in Japan. METHODS: Data on traffic accidents were collected from Fukuoka Prefectural Police records of traffic accidents which occurred in that prefecture between 1987 and 1996. Multiple logistic regression models were used to assess the effect of alcohol use on the risk of traffic-accident death. RESULTS: The data showed that 58,421 male drivers were involved in traffic accidents during the 10-year study period, and that 271 of these were killed as a result of the accident. Alcohol use was significantly associated with speed, seat belt use, time, and road form. Among male motorcar drivers, the odds ratio of alcohol use before driving, after adjusting for age, calendar year, time, and road form, was 4.08 (95% confidence interval, 3.08-5.40), which means that about 75% of fatalities (attributable risk percent among exposed) might have been prevented if drivers had not drunk before driving. CONCLUSIONS: Alcohol use before driving resulted in a 4.08-fold increase in the risk of death in a traffic accident. It is suggested that alcohol use is considered an important risk factor for fatality in traffic accidents.     

Phycoerythrin and photosynthesis of the pelagic blue-green alga Trichodesmium thiebautii in the waters of Kuroshio,Japan

The photosynthetic function of phycoerythrin was investigated in the alga Trichodesmium thiebautii from the waters of Kuroshio, Japan. The spectroscopic characteristics of the in vivo and isolated T. thiebautii phycoerythrin pigments are identical, and have 3 absorption bands at 495, 547 and 562 nm. Light at the wavelengths corresponding to each absorption band of phycoerythrin is equally efficient in T. thiebautii photosynthesis, indicating that phycoerythrin is active in trapping light energy for photosynthesis. In the natural habitat, phycoerythrin is considered to be the main photosynthetic pigment in T. thiebautii photosynthesis.     

Characterizing kinetics of transport and transformation of selenium in water-sediment microcosm free from selenium contamination using a simple mathematical model

This study developed a seven-compartment model for predicting the fate of selenium (Se) in an aquatic environment containing a water-sediment boundary. Speciation of Se in water-sediment microcosms under microaerobic conditions was measured to evaluate first-order kinetics of Se transportation and transformation. The microcosm consisted of a 10-ml solution containing 1mM soluble Se as selenate (Se6+) or selenite (Se4+) and 8 g wet sediment that was free from Se contamination, sampled from the Senri, Yamato, or Yodo Rivers in Osaka, Japan. Stepwise reaction coefficients describing transportation and transformation were determined using an inverse method on this model which includes: selenate (Se(W)6+) and selenite (Se(W)4+) in ponded water; selenate (Se(S)6+) and selenite (Se(S)4+), elemental Se (Se0), organic Se (Se2-) in sediment; and gaseous Se (DMSe). During this 1-month experiment, soluble Se was transported from ponded water to the sediment and Se was transformed sequentially to other Se species through biochemical reactions. Experimental and kinetic analyses indicated quantitatively that the Yamato River microcosm, with its high organic matter content, had a high adsorption rate of soluble Se. The Yodo River microcosm had a low adsorption rate for Se6+ and a low Se reduction rate. The Senri River microcosm had an apparent high volatilization rate of DMSe. The model developed in this study is extremely useful for predicting fate of Se in aquatic environment in the field.     

Influence of H<Subscript>2</Subscript> on the decomposition of halides by nonthermal plasma incorporated with in situ alkaline absorption

To control the emission of halides into the environment, an experiment on the nonthermal plasma decomposition of the halides CF₄, CHF₃, C₂HCl₃, and CHClF₂ was conducted in a wire-in-tube corona reactor. It was found that the decomposition of C₂HCl₃ and CHClF₂ was easy compared with the decomposition of CF₄ and CHF₃. With the addition of H₂ in N₂ gas, the decomposition ratio of CF₄, C₂HCl₃, and CHClF₂ increased. In contrast, the decomposition ratio of CHF₃ in a hydrogen-rich atmosphere was lower than that in an N₂ atmosphere. It was demonstrated that the yields of HF and/or HCl formed during halide decomposition clearly increased in the presence of H₂ in N₂ gas. Furthermore, in order to prevent the production of unwanted products from halide decomposition, a combination of plasma decomposition and in situ alkaline absorption was devised by coating a layer of Ca(OH)₂ onto the surface of the grounding electrode. It was demonstrated that the Ca(OH)₂ sorbent played an effective role as a scavenger, participating in halide decomposition by capturing reaction products such as HCl and HF, therefore resulting in increased halide decomposition.     

Diurnal and weekday variations in the source contributions of ozone precursors in California's South Coast Air Basin

For at least 30 years, ozone (O3) levels on weekends in parts of California's South Coast (Los Angeles) Air Basin (SoCAB) have been as high as or higher than on weekdays, even though ambient levels of O3 precursors are lower on weekends than on weekdays. A field study was conducted in the Los Angeles area during fall 2000 to test whether proposed relationships between emission sources and ambient nonmethane hydrocarbon (NMHC) and oxides of nitrogen (NOx) levels can account for observed diurnal and day-of-week variations in the concentration and proportions of precursor pollutants that may affect the efficiency and rate of O3 formation. The contributions to ambient NMHC by motor vehicle exhaust and evaporative emissions, estimated using chemical mass balance (CMB) receptor modeling, ranged from 65 to 85% with minimal day-of-week variation. Ratios of ambient NOx associated with black carbon (BC) to NOx associated with carbon monoxide (CO) were approximately 1.25 +/- 0.22 during weekdays and 0.76 +/- 0.07 and 0.52 +/- 0.07 on Saturday and Sunday, respectively. These results demonstrate that lower NOx emissions from diesel exhaust can be a major factor causing lower NOx mixing ratios and higher NMHC/NOx ratios on weekends. Nonmobile sources showed no significant day-of-week variations in their contributions to NMHC. Greater amounts of gasoline emissions are carried over on Friday and Saturday evenings but are, at most, a minor factor contributing to higher NMHC/NOx ratios on weekend mornings.