• Guidelines for developing optical clocks with 10-18 fractional frequency uncertainty 

  Abdel-Hafiz, Moustafa; Ablewski, Piotr; Al-Masoudi, Ali; Álvarez Martínez, Héctor; Balling, Petr; Barwood, Geoffrey; Benkler, Erik; Bober, Marcin; Borkowski, Mateusz; Bowden, William; Ciurylo, Roman; Cybulski, Hubert; Didier, Alexandre; Dolezal, Miroslav; Dörscher, Sören; Falke, Stephan; Godun, Rachel M.; Hamid, Ramiz; Hill, Ian R.; Hobson, Richard; Huntemann, Nils; Le Coq, Yann; Le Targat, Rodolphe; Legero, Thomas; Lindvall, Thomas; Lisdat, Christian; Lodewyck, Jerome; Margolis, Helen S.; Mehlstäubler, Tanja E.; Peik, Ekkehard; Pelzer, Lennart; Pizzocaro, Marco; Rauf, Benjamin; Rolland, Antoine; Scharnhorst, Nils; Schioppo, Marco; Schmidt, Piet O.; Schwarz, Roman; Senel, Cagri; Spethmann, Nicolas; Sterr, Uwe; Tamm, Christian; Thomsen, Jan W.; Vianello, Alvise; Zawada, Michal (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  There has been tremendous progress in the performance of optical frequency standards since the first proposals to carry out precision spectroscopy on trapped, single ions in the 1970s. The estimated fractional frequency ...
• Entanglement Swapping with Semiconductor-Generated Photons Violates Bell’s Inequality 

  Zopf, Michael; Keil, Robert; Chen, Yan; Yang, Jingzhong; Chen, Disheng; Ding, Fei; Schmidt, Oliver G. (College Park, MA : American Physical Society, 2019)

  Transferring entangled states between photon pairs is essential in quantum communication. Semiconductor quantum dots are the leading candidate for generating polarization-entangled photons deterministically. Here we show ...
• ADWICE: Advanced diagnosis and warning system for aircraft icing environments 

  Tafferner, A.; Hauf, T.; Leifeld, C.; Hafner, T.; Leykauf, H.; Voigt, U. (Boston, Massachusetts : American Meteorological Society, 2003)

  This paper describes the design of the Advanced Diagnosis and Warning System for Aircraft Icing Environments (ADWICE) and presents results for two different icing weather situations with typical icing conditions. ADWICE ...
• Klimawandel - Schicksal oder bewältigbare Herausforderung 

  Hauf, Thomas (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  no abstract available
• Der achte Tag : Oder Gott sah, dass es nicht gut war. Ein Dialog zwischen Grete, Mephisto und Gott 

  Hauf, Thomas (Hannover : Institutionelles Repositorium der Leibniz Universität Hannover, 2019)

  no abstract available
• Large eddy simulation of particle settling in the ocean mixed layer 

  Noh, Y.; Kang, I.S.; Herold, M.; Raasch, S. (College Park, MD : American Institute of Physics, 2006)

  The settling process of suspended particles in the turbulent flow was investigated by analyzing the Lagrangian motion of a large number of particles in the ocean mixed layer simulated by large eddy simulation (LES), focusing ...
• Modeling deep ocean convection: Large eddy simulation in comparison with laboratory experiments 

  Raasch, S.; Etling D. (Boston, Massachusetts : American Meteorological Society, 1998)

  A large-eddy simulation model (LES) has been applied to study deep convective processes in a stratified ocean driven by the energetic cooling at the ocean surface. Closely related to a recent laboratory experiment, the ...
• The role of preconditioning in the evolution of open-ocean deep convection 

  Noh, Y.; Cheon, W.G.; Raasch, S. (Boston, Massachusetts : American Meteorological Society, 2003)

  Large-eddy simulation of open-ocean deep convection shows that the evolution of convection appears in a fundamentally different pattern, depending on the precondition of the ocean and the magnitude of the surface buoyancy ...
• Large eddy simulation of the ocean mixed layer: The effects of wave breaking and langmuir circulation 

  Noh, Y.; Min, H.S.; Raasch, Siegfried (Boston, Massachusetts : American Meteorological Society, 2004)

  Large eddy simulation (LES) of the ocean mixed layer was performed in which both wave breaking and Langmuir circulation are realized. Wave breaking was represented by random forcing consistent with the observed near-surface ...
• The route to raindrop formation in a shallow cumulus cloud simulated by a Lagrangian cloud model 

  Hoffmann, Fabian; Noh, Yign; Raasch, Siegfried (Boston, Massachusetts : American Meteorological Society, 2017)

  The mechanism of raindrop formation in a shallow cumulus cloud is investigated using a Lagrangian cloud model (LCM). The analysis is focused on how and under which conditions a cloud droplet grows to a raindrop by tracking ...
• Large eddy simulation of thermally induced oscillations in the convective boundary layer 

  Letzel, M.O.; Raasch, S. (Boston, Massachusetts : American Meteorological Society, 2003)

  Mesoscale circulations induced by differential boundary layer heating due to surface inhomogeneities on scales of 5 km and more can significantly change the average properties and the structure of the convective boundary ...
• Influence of langmuir circulation on the deepening of the wind-mixed layer 

  Noh, Y.; Goh, G.; Raasch, S. (Boston, Massachusetts : American Meteorological Society, 2011)

  Analysis of large eddy simulation data reveals that Langmuir circulation (LC) induces a significant enhancement of the mixed layer deepening, only if the mixed layer depth (MLD) h is shallow and the buoyancy jump across ...
• A large-eddy simulation study of thermal effects on turbulent flow and dispersion in and above a street canyon 

  Park, S.-B.; Baik, J.-J.; Raasch, S.; Letzel, M.O. (Boston, Massachusetts : American Meteorological Society, 2012)

  Thermal effects on turbulent flow and dispersion in and above an idealized street canyon with a street aspect ratio of 1 are numerically investigated using the parallelized large-eddy simulation model (“PALM”). Each of ...
• Cell broadening revisited: Results from high-resolution large-eddy simulations of cold air outbreaks 

  Schröter, M.; Raasch, S.; Jansen, H. (Boston, Massachusetts : American Meteorological Society, 2005)

  Large-eddy simulations (LES) have been carried out in order to investigate the structure and development of organized mesoscale cellular convection (MCC) during cold air outbreaks (CAOB) and to reevaluate results by Müller ...
• Examination of the mixed layer deepening process during convection using LES 

  Noh, Y.; Goh, G.; Raasch, S. (Boston, Massachusetts : American Meteorological Society, 2010)

  Analysis of large-eddy simulation data of the ocean mixed layer under convection reveals that the contribution from wind stress decreases with time as a result of inertial oscillation in the extratropical ocean and that ...
• A refinement of the Millionshchikov quasi-normality hypothesis for convective boundary layer turbulence 

  Gryanik, V.M.; Hartmann, J.; Raasch, S.; Schröter, M. (Boston, Massachusetts : American Meteorological Society, 2005)

  The Millionshchikov hypothesis of quasi-normal distribution of fourth-order moments fails for convective conditions where the probability density functions of temperature and vertical velocity fluctuations are skewed. This ...
• Formation of a diurnal thermocline in the ocean mixed layer simulated by LES 

  Noh, Y.; Goh, G.; Raasch, S.; Gryschka, M. (Boston, Massachusetts : American Meteorological Society, 2009)

  The formation of a diurnal thermocline in the ocean mixed layer under a stabilizing buoyancy flux was simulated successfully by large-eddy simulation, reproducing various features consistent with observation. The analysis ...
• Evaporation over a heterogeneous land surface: The EVA-GRIPS Project 

  Mengelkamp, H.-T.; Beyrich, F.; Heinemann, G.; Ament, F.; Bange, J.; Berger, F.; Bösenberg, J.; Foken, T.; Hennemuth, B.; Heret, C.; Huneke, C.; Johnsen, K.-P.; Kerschgens, M.; Kohsiek, W.; Leps, J.-P.; Liebethal, C.; Lohse, H.; Mauder, M.; Meijninger, W.; Raasch, S.; Simmer, C.; Spieß, T. A.; Tittebrand, A.; Uhlenbrock, J.; Zittel, P. (Boston, Massachusetts : American Meteorological Society, 2006)

  The representation of subgrid-scale surface heterogeneities in numerical weather and climate models has been a challenging problem for more than a decade. The Evaporation at Grid and Pixel Scale (EVA-GRIPS) project adds ...
• A cloud microphysics parameterization for shallow cumulus clouds based on Lagrangian cloud model simulations 

  Noh, Yign; Oh, Donggu; Hoffmann, Fabian; Raasch, Siegfried (Boston, Massachusetts : American Meteorological Society, 2018)

  Cloud microphysics parameterizations for shallow cumulus clouds are analyzed based on Lagrangian cloud model (LCM) data, focusing on autoconversion and accretion. The autoconversion and accretion rates,A and C, respectively, ...
• A new research approach for observing and characterizing land-atmosphere feedback 

  Wulfmeyer, Volker; Turner, David D.; Baker, B.; Banta, R.; Behrendt, A.; Bonin, T.; Brewer, W.A.; Buban, M.; Choukulkar, A.; Dumas, E.; Hardesty, R.M.; Heus, T.; Ingwersen, J.; Lange, D.; Metzendorf, S.; Muppa, S.K.; Meyers, T.; Newsom, R.; Osman, M.; Raasch, S.; Santanello, J.C.; Senff, F.; Späth, F.; Wagner, T.; Weckwerth, T. (Boston, Massachusetts : American Meteorological Society, 2018)

  Forecast errors with respect to wind, temperature, moisture, clouds, and precipitation largely correspond to the limited capability of current Earth system models to capture and simulate land–atmosphere feedback. To ...

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