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This study addresses impact of wind, waves, tidal forcing and baroclinicity on the sea level of the German Bight during extremes. The role of waves-induced processes, tides and baroclinicity is quantified and the results are compared with observational data that include various in-situ measurements as well as satellite data. A coupled, high-resolution, model system is used to simulate the wind waves, water level and three-dimensional hydrodynamics. The effects of the wind waves on sea level variability are studied accounting for wave-dependent stress, wave-breaking parameterization and wave-induced effects on vertical mixing. The analyses of the coupled model results reveal a closer match with observations than for the stand-alone circulation model, especially during the extreme storm Xaver in December 2013. The predicted surge of the coupled model enhances significantly during extremes when considering wave-current interaction processes. The wave-dependent approach yields to a contribution of more than 30% in some coastal area during extremes. The improved skill resulting from the new developments justifies further use of coupled wave and three dimensional circulation models for improvement of coastal flooding predictions. [ABSTRACT FROM AUTHOR]

Chronic toxic and carcinogenic effects of gasoline engine exhaust inhalation were investigated in rats. The exhaust from the combustion of commercial fuel containing 30 ppm ferrocene additive was compared to exhaust from the same fuel without ferrocene. This study was part of a procedure to get a special authorization for the use of ferrocene as gasoline additive according to the German Gasoline Lead Act. To generate the exhausts, pairs of engines of the same type and age were operated on computer-controlled test benches in a combined urban–freeway driving cycle. The engines were equipped with three-way catalysts and lambda sensors. Rats inhaled the exhausts after dilution at ratios of about 1:20 and 1:40 for 18 h/day, 5 days/wk for 12 mo (chronic toxicity study) or for 24 mo followed by 6 mo of clean air (carcinogenicity study). The limiting factor for the exhaust concentration was the relative humidity of the exposure atmosphere. At defined intervals, body weight and food consumption, parameters of clinical chemistry, hematology, bronchoalveolar lavage (BAL), and mechanical lung function were measured, as well as lung clearance and particle retention in the lungs. In the high-dose groups and the controls the complete organ/tissue spectrum was investigated histopathologically, and in the low-dose groups the respiratory tract. Only slight exposure-related effects could be detected, like a loss in the background iron content of the cell pellet of the bronchoalveolar lavage fluid and cytoplasmic inclusions and goblet-cell hyperplasias in the nasal cavity. Between the clean-air controls and the exhaust-exposed groups, no exposure-related differences occurred in body weight development, mortality incidences, or any of the clinical investigations. Ninety-two to 94% of the animals developed age-related tumors, predominantly in the mammary glands, uterus, adrenals, thyroid, and pituitary. In the respiratory tract a total of five tumors was found: one in the controls and four in the low-dose groups. No physical, chemical, or toxicological differences between the exhausts from fuel without or with ferrocene were demonstrated. [ABSTRACT FROM AUTHOR]