A5057539477- Meteorological Phenomena and Simulations
- Climate variability and models
- Cryospheric studies and observations
- Geophysics and Gravity Measurements
- Atmospheric Ozone and Climate
- Ionosphere and magnetosphere dynamics
- Tropical and Extratropical Cyclones Research
- Atmospheric and Environmental Gas Dynamics
- Wind and Air Flow Studies
- Atmospheric chemistry and aerosols
- Landslides and related hazards
- Atmospheric aerosols and clouds
- Hydrology and Watershed Management Studies
- Plant Water Relations and Carbon Dynamics
- Climate change and permafrost
- Precipitation Measurement and Analysis
- Aeolian processes and effects
- Oceanographic and Atmospheric Processes
- Computational Geometry and Mesh Generation
- Fluid Dynamics and Turbulent Flows
- Peatlands and Wetlands Ecology
- 3D Modeling in Geospatial Applications
- Arctic and Antarctic ice dynamics
- Statistical and numerical algorithms
- Astronomical Observations and Instrumentation
German Meteorological Service
2015-2025
Ludwig-Maximilians-Universität München
2002-2012
Max Planck Institute for Meteorology
2011
Institut für Urheber- und Medienrecht
2006
Abstract This article describes the non‐hydrostatic dynamical core developed for ICOsahedral Non‐hydrostatic (ICON) modelling framework. ICON is a joint project of German Weather Service (DWD) and Max Planck Institute Meteorology (MPI‐M), targeting unified system global numerical weather prediction (NWP) climate modelling. Compared with existing models at both institutions, main achievements are exact local mass conservation, mass‐consistent tracer transport, flexible grid nesting capability...
Large‐eddy simulations (LES) with the new ICOsahedral Non‐hydrostatic atmosphere model (ICON) covering Germany are evaluated for four days in spring 2013 using observational data from various sources. Reference established Consortium Small‐scale Modelling (COSMO) numerical weather prediction and further standard LES codes performed used as a reference. This comprehensive evaluation approach covers multiple parameters scales, focusing on boundary‐layer variables, clouds precipitation. The...
Abstract ICON‐A is the new icosahedral nonhydrostatic (ICON) atmospheric general circulation model in a configuration using Max Planck Institute physics package, which originates from ECHAM6 model, and has been adapted to account for changed dynamical core framework. The coupling scheme between dynamics employs sequential updating by physics, fixed sequence of physical processes similar ECHAM6. To allow meaningful initial comparison established ECHAM6‐LR setup with similar, low resolution...
Abstract ICON (ICOsahedral Nonhydrostatic) is a unified modeling system for global numerical weather prediction (NWP) and climate studies. Validation of its dynamical core against test suite forecasting has been recently published by Zängl et al. (2014). In the present work, an extension presented that enables it to perform as large eddy simulation (LES) model. The details implementation LES turbulence scheme in are explained cases performed validate two standard models. Despite limitations...
Abstract. As part of a broader effort to develop next-generation models for numerical weather prediction and climate applications, hydrostatic atmospheric dynamical core is developed as an intermediate step evaluate finite-difference discretization the primitive equations on spherical icosahedral grids. Based need mass-conserving discretizations multi-resolution modelling well scalability efficiency massively parallel computing architectures, built triangular C-grids using relatively small...
The polar and subpolar tropopause in both hemispheres is investigated using the ECMWF Reanalysis (ERA) data from 1979 to 1993 radiosonde 1989 1993. Both thermal dynamical criteria are applied each dataset. tropopauses derived used validate ERA-derived investigate sharpness of tropopause. validation reveals that ERA well suited for determination A comparison between shows a very good agreement except winter, there clear evidence criterion more appropriate winter. results show annual cycle can...
A set of modifications is presented to reduce the unphysical impact horizontal diffusion in numerical models with a terrain-following sigma-coordinate system. At model levels sufficiently far away from ground, vertical interpolation used compute truly horizontally when coordinate surfaces are sloping. Close where computation not everywhere possible without intersecting topography, combination one-sided and orography-adjusted along sigma for most variables. The latter means that coefficient...
Abstract The improvement of Quantitative Precipitation Forecasting (QPF) in mountainous regions was a major supporting objective the Mesoscale Alpine Programme (MAP) project P1 devoted to study orographic precipitation. This paper reviews main MAP‐related achievements regarding QPF and highlights MAP impact on developing research planning future operational strategies. Recent results based case‐studies, data analysis assimilation, quantification model uncertainties, intercomparison...
Abstract. We present the first stage of a new online-coupled global to regional-scale modeling framework for simulation spatiotemporal evolution aerosols and trace gases. The underlying meteorological model is nonhydrostatic system ICON (ICOsahedral Nonhydrostatic) which allows local grid refinement with two-way interactions between grids. develop extension ART (Aerosol Reactive Trace gases) goal simulating substances state atmosphere. Within this paper, we basic equations give an overview...
Abstract. How the upper-atmosphere branch of circulation contributes to and interacts with middle lower atmosphere is a research area many open questions. Inertia–gravity waves, for instance, have moved in focus as they are suspected be key features driving shaping circulation. Numerical atmospheric models an important pillar this research. We use ICOsahedral Non-hydrostatic (ICON) general model, which joint development Max Planck Institute Meteorology (MPI-M) German Weather Service (DWD),...
Abstract. In climate modelling, the reality of simulated flows in middle atmosphere is largely affected by model's representation gravity wave processes that are unresolved, while these usually simplified to facilitate computations. The simplification commonly applied existing models neglect propagation horizontal direction and time. Here we use a model fully represents unresolved waves all directions, thereby elucidating its dynamical effect upon most important mode tropical...
Abstract An overview of advances in the observation, modelling, forecasting, and understanding flows through gaps achieved Mesoscale Alpine Programme is given. Gaps are lateral constrictions topography (level gaps) often combined with vertical terrain changes (passes). Of possible flow configurations, only an asymmetric one (relatively deep slow upstream, accelerating thinning downstream), which connects two different ‘reservoirs’ on each side gap, examined. The strongly nonlinear, making...
We present a technique to synthesise telluric absorption and emission features both for in-situ wavelength calibration their removal from astronomical spectra. While the presented is applicable wide variety of optical infrared spectra, we concentrate in this paper on selected high-resolution near-infrared spectra obtained with CRIRES spectrograph demonstrate its performance limitation. find that synthetic reproduce about 2%, even close saturated line cores. Thus, could be used replace...
Abstract To extend the numerical stability limit over steep slopes, a truly horizontal pressure-gradient discretization based on ideas formulated by Mahrer in 1980s has been developed. Conventionally, pressure gradient is evaluated terrain-following coordinate system, which necessitates metric correction term that prone to instability if height difference between adjacent grid points much larger than vertical layer spacing. The alternative way pursued here reconstruct at auxiliary lying same...
We present ICON-waves, a new component of the ICOsahedral Non-hydrostatic (ICON) modeling system, designed to explicitly model ocean surface gravity waves and their feedbacks on atmosphere within Earth system. Until now, ICON-NWP model, developed routinely operated by German Weather Service (DWD), has not fully captured impact wave-induced interactions. Waves influence sea state, generate turbulence, modify currents, affect air-sea exchanges heat, matter, momentum. ICON-waves addresses these...
Abstract. For the first time, Limited-Area Mode of new ICON (Icosahedral Nonhydrostatic) weather and climate model has been used for a continuous long-term regional simulation over Europe. Built upon (ICON-LAM), ICON-CLM (ICON in Climate Limited-area Mode, hereafter ICON-CLM, available release version 2.6.1) is an adaptation applications. A now already integrated into starter package (ICON-CLM_SP_beta1). The provides users with technical infrastructure that facilitates simulations as well...
Abstract Parameterizations for internal gravity waves in atmospheric models are traditionally subject to a number of simplifications. Most notably, they rely on both neglecting wave propagation and advection the horizontal direction (single-column assumption) an instantaneous balance vertical (steady-state assumption). While these simplifications well justified cover some essential dynamic effects keep computational effort small, it has been shown that mechanisms potentially significant. In...
A case study of a south foehn windstorm observed across the Brenner Pass in Wipp Valley near Austrian–Italian border is presented based on detailed comparison and verification high-resolution numerical simulations with observations. The event 24 through 25 October 1999 was part Intensive Observing Period 10 Mesoscale Alpine Programme (MAP). were performed fifth-generation Pennsylvania State University–NCAR Model (MM5). observations collected ground-based scanning Doppler lidar, an airborne...
Abstract Wind‐induced snow transport has remarkable effects on the cover spatial variability and temporal dynamics of snowmelt runoff. For accurate modelling, valid atmospheric forcing fields are essential. Since it is impossible to generate appropriate wind by a simple interpolation station data, new approach was developed: A modified version Penn State University‐National Centre for Atmospheric Research (MM5) model used with 200‐m resolution. Because high computational costs MM5, not...
Three-dimensional simulations of the daytime thermally induced valley wind system for an idealized valley–plain configuration, obtained from nine nonhydrostatic mesoscale models, are compared with special emphasis on evolution along-valley wind. The models use same initial and lateral boundary conditions, standard parameterizations turbulence, radiation, land surface processes. mean (averaged over cross section) is similar all except a time shift between individual up to 2 h slight...
Abstract. Snow transport is one of the most dominant processes influencing snow cover accumulation and ablation in high mountain environments. Hence, spatial temporal variability significantly modified with respective consequences on total amount water pack, dynamics runoff energy balance surface. For present study we used model SnowModel combination MM5 (Penn State University – National Center for Atmospheric Research model) generated wind fields. In a first step fields were downscaled by...
Abstract. Atmospheric composition studies on weather and climate timescales require flexible, scalable models. The ICOsahedral Nonhydrostatic model with Aerosols Reactive Trace gases (ICON-ART) provides such an environment. Here, we introduce the most up-to-date version of flexible tracer framework for ICON-ART explain its application in one numerical forecast related case study. We demonstrate implementation idealised tracers chemistry tendencies different complexity using ART...
Parametrizations for internal gravity waves in atmospheric models are traditionally subject to a number of simplifications. Most notably, they rely on both neglecting wave propagation and advection the horizontal direction (single-column assumption) an instantaneous balance vertical (steady-state assumption). While these simplifications well justified cover some essential dynamic effects keep computational effort small it has been shown that mechanisms potentially significant. In particular,...