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Zeitreihen von Monatsmittelwerten des Windes in der Mesosphäre/unteren Thermosphäre über Collm werden auf mögliche Korrelationen mit der Nordatlantischen Oszillation (NAO) und der Südlichen Oszillation (SO) hin untersucht. Während eine positive Korrelation bis in die 1990er Jahre existiert, schwächt sich diese in der Folge ab und kehrt sich teilweise um. Da NAO und SO gekoppelt sind, erfolgen diese Änderungen etwa zur selben Zeit. Die Änderung der Kopplung steht wahrscheinlich in Verbindung mit einer generellen Änderung der Dynamik der mittleren Atmosphäre.

Zeitreihen von Monatsmittelwerten des Windes in der Mesosphäre/unteren Thermosphäre über Collm werden auf mögliche Korrelationen mit der Nordatlantischen Oszillation (NAO) und der Südlichen Oszillation (SO) hin untersucht. Während eine positive Korrelation bis in die 1990er Jahre existiert, schwächt sich diese in der Folge ab und kehrt sich teilweise um. Da NAO und SO gekoppelt sind, erfolgen diese Änderungen etwa zur selben Zeit. Die Änderung der Kopplung steht wahrscheinlich in Verbindung mit einer generellen Änderung der Dynamik der mittleren Atmosphäre.

Concentrations of harmful airborne substances are much higher in indoor air than outdoors. Furniture, cleansing agents, paints, solvents, carpets and floors release numerous volatile organic compounds (VOCs), which can only be reduced through adequate ventilation. The present investigation considered data of 463 participants in the fourth year of age within a project of the Helmholtz Centre for Environmental Research. 39 of them developed wheezing symptoms, 148 bronchitis and 397 infections. A novel model, based on logistic regression, was used to find associations between certain VOC concentrations and the outcome of airway diseases. The analysis involved gender, contact with cats, environmental tobacco smoke (ETS), and the prevalence of atopy in both parents. The aim was to find threshold concentrations of VOCs and to give recommendations for the abatement of environmentally caused diseases. The present research proved findings of other studies, for instance, that “wheezing ever” appeared when high concentrations of hexane, benzene, ethylbenzene, and chlorbenzene were reported. Such relationships were observed for “wheezing ever” in the past year. The number of wheezing participants was low (39) and, therefore, also some other airway diseases (infection, bronchitis and asthma) were tested for their relationship to VOC concentrations.

Spectral reflectivity and albedo are obtained from airborne measurements of spectral irradiance and radiance during two field campaigns in Leipzig, Germany and Zhongshan, China. The data measured above urban and rural areas have been investigated with respect to the heterogeneity and anisotropy of the surface. Furthermore the spectral albedo and reflectivity measured above the same surface but at different flight altitudes have been analyzed. These data is used to estimate the impact of multiple scattering processes by aerosol particles and gas molecules.

A description and some results of the calculated aeolian sand transport including the turbulence intensity and the autocorrelation of the wind field in the transport equation’s are presented in this study. The simulated transport related to Sørensen (2004) transport equation varies by more than 100% for one and the same friction velocity and one and the same sand type near the thresholds by variation of turbulence intensity and/or the autocorrelation of the wind. Published results of sand transport measurements are imperfect and not comparable without information about the characteristics of the turbulent wind. An indication of friction velocity, threshold friction velocity and measured transport must be supplement by the specification of the turbulence intensity and the autocorrelation of the wind velocity.