Development of a satellite SAR image spectra and altimeter wave height data assimilation system for ERS-1

The applicability of ERS-1 wind and wave data for wave models was studied using the WAM third generation wave model and SEASAT altimeter, scatterometer and SAR data. A series of global wave hindcasts is made for the surface stress and surface wind fields by assimilation of scatterometer data for the full 96-day SEASAT and also for two wind field analyses for shorter periods by assimilation with the higher resolution ECMWF T63 model and by subjective analysis methods. It is found that wave models respond very sensitively to inconsistencies in wind field analyses and therefore provide a valuable data validation tool. Comparisons between SEASAT SAR image spectra and theoretical SAR spectra derived from the hindcast wave spectra by Monte Carlo simulations yield good overall agreement for 32 cases representing a wide variety of wave conditions. It is concluded that SAR wave imaging is sufficiently well understood to apply SAR image spectra with confidence for wave studies if supported by realistic wave models and theoretical computations of the strongly nonlinear mapping of the wave spectrum into the SAR image spectrum. A closed nonlinear integral expression for this spectral mapping relation is derived which avoids the inherent statistical errors of Monte Carlo computations and may prove to be more efficient numerically

"Früher gab's schöne Menschen, jetzt gibt's schöne Häuser"

Die vorliegende Masterarbeit hat zum Ziel, Gentrificationprozesse aus der subjektiven Alltagsperspektive von Langzeitbewohner_innen zu erforschen. Den geografischen Rahmen als Untersuchungsquartier bildet hierfür der Helmholtzkiez in Berlin Prenzlauer Berg. Bei Gentrification handelt es sich um ein innenstädtisches Phänomen, bei dem es durch Investitionen und den Zuzug neuer Gruppen zu einer baulichen Aufwertung und einer soziokulturellen Umwertung eines Quartiers kommt. Dieser Wandel kann durch idealtypische Phasenverläufe beschrieben und mit ökonomischen Theorien und Theorien über die neuen Nachfrager_innengruppen erklärt werden. Mit dieser theoretischen Basis wird im Rahmen eines qualitativen Forschungsdesigns der Wandel im Helmholtzquartier untersucht. Erhoben wird mittels narrativer Interviews, Expert_inneninterviews und teilnehmender Beobachtung. Die Analyse erfolgt mittels Grounded Theory. Zu den hauptsächlichen Ergebnissen der Untersuchung gehört der spezifische historische Rahmen der DDR, welcher die Gentrificationprozesse im Quartier stark beeinflusst. Politische und stadtplanerische Implikationen wirken vor allem über die Deklaration des Sanierungsgebietes. Für die Bewohner_innen hat der Wandel Konsequenzen in Form von Verdrängung durch hohe Mieten und kulturelle Entfremdung. Des weiteren wurden Bedrohungs- und Verunsicherungsphasen in den Erzählungen ausgemacht

Sea Surface Roughness Observed by High Resolution Radar

Changes in the sea surface roughness are usually associated with a change in the sea surface wind field. This interaction has been exploited to measure the sea surface wind speed by scatterometry. A number of features on the sea surface associated with changes in roughness can be observed by synthetic aperture radar (SAR) because of the change in Bragg backscatter of the radar signal by damping of the resonant ocean capillary waves. With various radar frequencies, resolutions, and modes of polarization, sea surface features have been analyzed in numerous campaigns, bringing various datasets together, thus allowing for new insights in small-scale processes at a larger areal coverage. This Special Issue aims at investigating sea surface features detected by high spatial resolution radars, such as SAR

Opažanja sjeveroistočno-jadranske bure pomoću satelita TerraSAR-X: rani rezultati

Some early results of the TerraSAR-X observations of the northeastern Adriatic bora wind are presented in this paper. TerraSAR-X is a German X-band radar satellite launched in 2007 that carries phased array X-band synthetic aperture radar (SAR) operating in different polarizations and providing multiple imaging modes. SAR backscatter can be used to derive wind fields at spatial resolution that no other instrument can provide. Terrain-induced jet and wake patterns are particularly conductive to the SAR-instrument examination. Bora, a cold and dry downslope wind blowing from north-easterly directions on the eastern side of the Adriatic Sea, exhibits such a response. Since bora is primarily winter wind and the town of Senj is known for frequent and severe bora episodes we focus on TerraSAR-X scenes collected in the winters of 2011 and 2012 over an area with Senj roughly in its center. Recently developed XMOD2 geophysical model function is used for wind magnitude derivation, whereas the WRF model was employed to estimate the wind direction. The selected TerraSAR-X scenes have captured representative bora events exhibiting rich details in bora-induced jet and wake patterns on the lee of the Dinaric Alps. The details registered in the normalized radar cross section response strongly suggest the need for still higher resolution numerical simulations in order to properly model the orographic impact on and the fine details in the surface wind field. Comparisons with both research and operational modeling results indicate that the currently used geophysical model function may benefit from enlarging the matchup data base with samples of severe winds.U radu su prikazani rani rezultati detekcije bure na sjeveroistočnoj strani Jadrana pomoću satelita TerraSAR-X. TerraSAR-X je njemački satelit lansiran 2007. godine koji nosi „phased- array“ radar sintetičke aperture (SAR) s mogućnošću rada uz različite polarizacije i uz više načina snimanja. Povratno zračenje instrumenta SAR može se iskoristiti za određivanje polja vjetra uz prostorno razlučivanje koje ne omogućuje ni jedan drugi instrument. Područja niskih mlaznih struja i zavjetrinske tišine, uzrokovana terenom, posebno su podatni za ispitivanja pomoću instrumenta SAR. Bura - hladan, suh i jak planinski vjetar koji puše iz sjeverno istočnih smjerova na istočnoj strani Jadranskog mora, izaziva spomenuti odziv. Kako je bura primarno zimski vjetar a senjsko područje poznato po čestim epizodama olujne bure, rad je fokusiran na TerraSAR-X scene registrirane tijekom zima 2011. i 2012. godine u širem području približno centriranom na Senj. Nedavno razvijena geofizička modelska funkcija XMOD2 korištena je za određivanje brzine vjetra a WRF model za procjenu njegova smjera. Odabrane TerraSAR scene pokrivaju reprezentativne epizode bure te pokazuju bogatstvo detalja u daljinskim zapisima niskih mlaznih struja i zavjetrinskih struktura koji nastaju na jadranskoj strani Dinarida. Detalji zabilježeni u odzivnom normaliziranom radarskom presjeku uvjerljivo sugeriraju potrebu još boljeg prostornog razlučivanja u numeričkim simulacijama da bi se ispravno modeliralo orografski utjecaj i detalje pripovršinskog polja vjetra. Usporedbe s rezultatima, kako istraživačkog tako i operativnog modeliranja, ukazuju da bi proširenje baždarne baze podataka uzorcima olujnog i orkanskog vjetra moglo poboljšati geofizičku modelsku funkciju

Grasping Virtual Objects Benefits Lower Aptitude Learners’ Acquisition of Foreign Language Vocabulary

Acknowledgements Special thanks go to the Ars Electronica Centre, Linz, and to co-workers who aided in the study implementation, particularly Christoph Kremer, Erika Mondria, and the staff of the Future Lab. Supported by the Johannes Kepler Open Access Publishing Fund. Funding Open access funding provided by Johannes Kepler University Linz.Peer reviewedPublisher PD

Comparing wavelengths simulated by the coastal wave model CWAM and TerraSAR-X satellite data

The accuracy of the high resolution coastal wave forecast model CWAM is validated on the basis of sea state information from satellite images of TerraSAR-X (TS-X). Employing 2-dimensional Fast Fourier Transformation, image spectra are derived from TS-X and locally varying patterns of the peak wavelengths are provided. Subsequently, wavelength comparisons are performed between a typical set of TS-X scenes acquired in December 2013 over the German Bight and the model hindcasts. This results mostly in reasonable agreement. Potential wave modelling errors are discussed as well

Changemaker – Studierende als Multiplikator:innen zur Förderung von Entrepreneurship-Kompetenzen

Eine Möglichkeit, die Gesellschaft auf neuartige Herausforderungen vorzubereiten, stellt die Etablierung der Social Entrepreneurship Education dar. Diese soll zunehmend für soziale Anliegen der Zivilgesellschaft sensibilisieren. Universitäten sind daher aufgefordert, neben Forschung und Lehre, verstärkt die Dritte Mission zu fokussieren. Die Zusammenarbeit von Wissenschaft und Schule im Rahmen von Campus Community Partnerschaften ermöglicht es Studierenden, als Multiplikator:innen die Entwicklung von Entrepreneurship-Kompetenzen von Volksschulkindern anzustoßen. Im Beitrag wird das Changemaker-Programm mit dem Ziel, die Entwicklung von Kompetenzen unternehmerischen Denkens und Handelns sowie sozialer wie auch gesellschaftlicher Innovationskraft zu fördern, vorgestellt

Relative Abundance of Bacillus spp., Surfactant-Associated Bacterium Present in a Natural Sea Slick Observed by Satellite SAR Imagery over the Gulf of Mexico

The damping of short gravity-capillary waves (Bragg waves) due to surfactant accumulation under low wind speed conditions results in the formation of natural sea slicks. These slicks are detectable visually and in synthetic aperture radar satellite imagery. Surfactants are produced by natural life processes of many marine organisms, including bacteria, phytoplankton, seaweed, and zooplankton. In this work, samples were collected in the Gulf of Mexico during a research cruise on the R/V F.G. Walton Smith to evaluate the relative abundance of Bacillus spp., surfactant-associated bacteria, in the sea surface microlayer compared to the subsurface water at 0.2 m depth. A method to reduce potential contamination of microlayer samples during their collection on polycarbonate filters was implemented and advanced, including increasing the number of successive samples per location and changing sample storage procedures. By using DNA analysis (real-time polymerase chain reaction) to target Bacillus spp., we found that in the slick areas, these surfactant-associated bacteria tended to reside mostly in subsurface waters, lending support to the concept that the surfactants they may produce move to the surface where they accumulate under calm conditions and enrich the sea surface microlayer