Influence of grid aspect ratio on planetary boundary layer turbulence in large-eddy simulations
Summary: The large grid aspect ratio of horizontal to vertical grid spacing is traditionally used in atmospheric large-eddy simulations. The grid aspect ratio could have influences on the simulated turbulence in the atmosphere. In this study, the influences are investigated with a series of sensitivity tests with parameter sweeps of spatial resolution and grid aspect ratio. We confirmed that the grid aspect ratio should be taken account in the sub-grid model to reproduce the theoretical energy spectrum.
Geosci. Model Dev. Discuss., 8, 6021-6094, doi:10.5194/gmdd-8-6021-2015, 2015
Adjoint of the Global Eulerian–Lagrangian Coupled Atmospheric transport model (A-GELCA v1.0): development and validation
Geosci. Model Dev. Discuss., 8, 5983-6019, doi:10.5194/gmdd-8-5983-2015, 2015
A Stochastic, Lagrangian Model of Sinking biogenic aggregates in the ocean (SLAMS 1.0): model formulation, validation and sensitivity
Geosci. Model Dev. Discuss., 8, 5931-5982, doi:10.5194/gmdd-8-5931-2015, 2015
Modelling the dispersion of particle numbers in five European cities
Geosci. Model Dev. Discuss., 8, 5873-5930, doi:10.5194/gmdd-8-5873-2015, 2015
Variability of phenology and fluxes of water and carbon with observed and simulated soil moisture in the Ent Terrestrial Biosphere Model (Ent TBM version 188.8.131.52.0)
Summary: The Ent Terrestrial Biosphere Model is a mixed-canopy dynamic global vegetation model developed specifically for coupling with land surface hydrology and general circulation models. This study describes the leaf phenology submodel implemented in the Ent TBM. We evaluate the performance in reproducing observed leaf seasonal growth as well as water and carbon fluxes for four plant functional types at five Fluxnet sites.
Geosci. Model Dev. Discuss., 8, 5809-5871, doi:10.5194/gmdd-8-5809-2015, 2015
Evaluation of lateral boundary conditions in a regional chemical transport model
Summary: This study investigate the representation of hemispheric transport in a regional chemical transport model (CTM) in terms of lateral boundary conditions (LBCs). We evaluate the LBCs both directly with satellite retrievals and indirectly by forcing a regional CTM with LBCs and compare to in-domain observations. We believe that our work makes an important contribution to the methodology of validating LBCs for regional modelling.
Geosci. Model Dev. Discuss., 8, 5763-5808, doi:10.5194/gmdd-8-5763-2015, 2015
Distributed visualization of gridded geophysical data: a web API for carbon flux
Summary: The Carbon Data Explorer is presented as a prototype application for data management, analysis, visualization, and sharing of Earth system science datasets, particularly gridded spatiotemporal datasets (e.g., NASA Level III data products) such as gridded climate model predictions and reanalysis data. In response to CMIP6, the Carbon Data Explorer provides a framework for the distributed analysis of climate model outputs. It is hoped that it will inspire the future development of similar tools.
Geosci. Model Dev. Discuss., 8, 5741-5761, doi:10.5194/gmdd-8-5741-2015, 2015
Development and evaluation of CNRM Earth-System model – CNRM-ESM1
Summary: This paper presents the first IPCC-class Earth system model developed at Centre National de Recherches Météorologiques (CNRM-ESM1). We detail how the various carbon reservoirs were initialized and analyze the behavior of the carbon cycle and its prominent physical drivers, comparing model results to the most up-to-date climate and carbon cycle dataset over the latest decades.
Geosci. Model Dev. Discuss., 8, 5671-5739, doi:10.5194/gmdd-8-5671-2015, 2015
Experiments on sensitivity of meridional circulation and ozone flux to parameterizations of orographic gravity waves and QBO phases in a general circulation model of the middle atmosphere
Summary: We implemented improved parameterizations of orographic gravity wave dynamical and thermal effects and QBO flows into a general circulation model and study the sensitivity of meridional circulation and vertical velocity to the parameterizations at altitudes up to 100km. Stationary OGW effects gives changes up to 40% in the meridional velocity and associated ozone fluxes in the stratosphere. Transitions from the easterly to westerly QBO phase may alter meridional and vertical velocities by 60%.
Geosci. Model Dev. Discuss., 8, 5643-5670, doi:10.5194/gmdd-8-5643-2015, 2015
Transient simulations of the present and the last interglacial climate using a coupled general circulation model: effects of orbital acceleration
Geosci. Model Dev. Discuss., 8, 5619-5641, doi:10.5194/gmdd-8-5619-2015, 2015
An approach for coupling higher and lower levels in marine ecosystem models and its application to the North Sea
Summary: This paper is a description of how very different higher and lower trophic level models (Ecopath with Ecosim) and ERSEM respectively can be coupled together using a metadata coupling system together with a number of examples of short and long range projections for end to end modelling. An extended discussion section outlines the challenges that will need to be met to develop useful end to end ecological modelling systems
Geosci. Model Dev. Discuss., 8, 5577-5618, doi:10.5194/gmdd-8-5577-2015, 2015
Upscaling with the dynamic two-layer classification concept (D2C): TreeMig-2L, an efficient implementation of the forest-landscape model TreeMig
Summary: Dynamic vegetation models (DVMs) often have high computational expenses, which the presented dynamic two-layer classification concept (D2C) aims to reduce. When implementing D2C into a DVM, a new layer for the dynamic grouping of grid-cells with similar climate and species compositions is introduced. The grouping of cells reduces the number of required calculations. With TreeMig-2L, I present how D2C can be implemented in a DVM and demonstrate that D2C can strongly reduce computational expenses.
Geosci. Model Dev. Discuss., 8, 5535-5575, doi:10.5194/gmdd-8-5535-2015, 2015
Discrete-Element bonded particle Sea Ice model DESIgn, version 1.3 – model description and implementation
Summary: Recent developments in observational and modeling techniques allow us to analyze sea ice with increasingly higher resolution. Instead of a continuous ice cover we observe a complex, constantly changing medium composed of interacting floes. Understanding these aspects of sea ice behavior requires new modeling methods, like the Discrete Element Sea Ice model DESIgn in which sea ice is treated as an assemblage of grains that freeze together or break apart in response to wind and ocean currents.
Geosci. Model Dev. Discuss., 8, 5481-5533, doi:10.5194/gmdd-8-5481-2015, 2015
Sensitivity of the WRF model to PBL parametrizations and nesting techniques: evaluation of surface wind over complex terrain
Geosci. Model Dev. Discuss., 8, 5437-5479, doi:10.5194/gmdd-8-5437-2015, 2015
Application of all relevant feature selection for failure analysis of parameter-induced simulation crashes in climate models
Summary: Climate simulation crashes are caused by inadeqaute knowledge of parameters in models describing physical phenomena. We have performed reanalysis of the data on simulation crashes and have shown that they can be attributed to three parameters of the ocean model. This is significant improvement over original study, where crashes were attributed to eight parameters. Our results will help researchers to develop improved models.
Geosci. Model Dev. Discuss., 8, 5419-5435, doi:10.5194/gmdd-8-5419-2015, 2015
Simulation of atmospheric N2O with GEOS-Chem and its adjoint: evaluation of observational constraints
Summary: This paper introduces a new inversion framework for N2O using GEOS-Chem and its adjoint, which we employed in a series of observing system simulation experiments to evaluate the source and sink constraints provided by surface and aircraft-based N2O measurements. We also applied a new approach for estimating a posteriori uncertainty for high-dimensional inversions, and used it to quantify the spatial and temporal resolution of N2O emission constraints achieved with the current observing network.
Geosci. Model Dev. Discuss., 8, 5367-5418, doi:10.5194/gmdd-8-5367-2015, 2015
Development of a numerical system to improve particulate matter forecasts in South Korea using geostationary satellite-retrieved aerosol optical data over Northeast Asia
Summary: We developed an integrated air quality modeling system using AOD data retrieved from a geostationary satellite sensor, GOCI (Geostationary Ocean Color Imager) over Northeast Asia with an application of spatio-temporal kriging method, and conducted short-term hindcast runs using the developed system. It appears that the ST-kriging approach can greatly reduce not only the errors and biases of AOD and PM10 predictions but also a computational burden of chemical weather forecast (CWF).
Geosci. Model Dev. Discuss., 8, 5315-5366, doi:10.5194/gmdd-8-5315-2015, 2015
Adaptive wavelet simulation of global ocean dynamics
Summary: In order to easily enforce solid-wall boundary conditions in the presence of complex coastlines, we propose a new mass and energy conserving Brinkman penalization for the rotating shallow water equations. This penalization does not lead to higher wave speeds in the solid region. The error estimates for the penalization are derived analytically and verified numerically for linearized one dimensional equations. The penalization is implemented in a conservative dynamically adaptive wavelet method
Geosci. Model Dev. Discuss., 8, 5265-5313, doi:10.5194/gmdd-8-5265-2015, 2015
Implementation of an optimal stomatal conductance model in the Australian Community Climate Earth Systems Simulator (ACCESS1.3b)
Summary: We implement a new stomatal conductance model within a land surface model coupled to a global climate model. The new model differs from the default in that it allows model parameters to vary by the different plant functional types, derived from global synthesis of observations. We show that the new scheme results in improvements in the model climatology and improves existing biases by up to 10-20%.
Geosci. Model Dev. Discuss., 8, 5235-5264, doi:10.5194/gmdd-8-5235-2015, 2015
FORest canopy atmosphere transfer (FORCAsT) 1.0: a 1-D model of biosphere–atmosphere chemical exchange
Summary: Volatile organic compounds released from forests into the atmosphere play a key role in governing atmospheric concentrations of trace gases and aerosol particles. We describe the development of a 1-D model that simulates the processes occurring within and above the forest canopy that regulate the transfer of these compounds and their products. We evaluate model performance by comparison of modelled concentrations against measurements from a field campaign at a northern Michigan forest site.
Geosci. Model Dev. Discuss., 8, 5183-5234, doi:10.5194/gmdd-8-5183-2015, 2015
A soil diffusion-reaction model for surface COS flux: COSSM v1
Geosci. Model Dev. Discuss., 8, 5139-5182, doi:10.5194/gmdd-8-5139-2015, 2015
A simplified gross primary production and evapotranspiration model for boreal coniferous forests – is a generic calibration sufficient?
Geosci. Model Dev. Discuss., 8, 5089-5137, doi:10.5194/gmdd-8-5089-2015, 2015
A unified parameterization of clouds and turbulence using CLUBB and subcolumns in the Community Atmosphere Model
Summary: This study evaluates a unified cloud parameterization and a Monte Carlo microphysics interface that is implemented in CAM v5.3. We show mean climate and tropical variability results from global simulations. The model has a degradation in precipitation skill but improvements in short-wave cloud forcing, liquid water path, long-wave cloud forcing, precipitable water, and tropical wave simulation. We also show estimation of computational expense and sensitivity to number of subcolumns.
Geosci. Model Dev. Discuss., 8, 5041-5088, doi:10.5194/gmdd-8-5041-2015, 2015
Modelling Mediterranean agro-ecosystems by including agricultural trees in the LPJmL model
Geosci. Model Dev. Discuss., 8, 4997-5040, doi:10.5194/gmdd-8-4997-2015, 2015
Conservative interpolation between general spherical meshes
Geosci. Model Dev. Discuss., 8, 4979-4996, doi:10.5194/gmdd-8-4979-2015, 2015
CranSLIK v2.0: improvements on the stochastic prediction of oil spill transport and fate using approximation methods
Summary: CranSLIK is a model that predicts the movement and spread of a surface oil spill at sea via a statistical approach that takes into account the random, and hence unpredictable nature, of the affecting parameters. CranSLIK v2.0 demonstrated significant forecasting improvements by capturing the oil spill accurately in real oil spill validation cases and also proved capable of simulating a broader range of oil spill scenarios, while maintaining the run time efficiency of the method.
Geosci. Model Dev. Discuss., 8, 4949-4977, doi:10.5194/gmdd-8-4949-2015, 2015
Competition between plant functional types in the Canadian Terrestrial Ecosystem Model (CTEM) v. 2.0
Summary: We use a modified form of the Lotka-Volterra (L-V) equations to simulate competition between plant functional types (PFTs) on a global-scale with the Canadian Terrestrial Ecosystem Model (CTEM) version 2.0. Our modified L-V simulations compare well against observation-based records of PFT distributions, while simulations with unmodified L-V equations show significant biases. We include an appendix detailing all aspects of CTEM v. 2.0.
Geosci. Model Dev. Discuss., 8, 4851-4948, doi:10.5194/gmdd-8-4851-2015, 2015
Development of a chlorine chemistry module for the Master Chemical Mechanism
Geosci. Model Dev. Discuss., 8, 4823-4849, doi:10.5194/gmdd-8-4823-2015, 2015
Modelling spatial and temporal vegetation variability with the Climate Constrained Vegetation Index: evidence of CO2 fertilisation and of water stress in continental interiors
Summary: A model was developed to simulate spatio-temporal variations in vegetation in response to temperature, precipitation and atmospheric CO2 levels. The model reproduced variations in vegetation well; it showed a greater response to drought stress in N Hemisphere continents than previous implementations and showed a decline in vegetation during the US dust bowl (1930s and 1950s) and the drought of the century in the Sahel (1984). Vegetation greenness increased in response to atmospheric CO2 levels.
Geosci. Model Dev. Discuss., 8, 4781-4821, doi:10.5194/gmdd-8-4781-2015, 2015
Accounting for anthropic energy flux of traffic in winter urban road surface temperature simulations with TEB model
Summary: An experimental study was conducted to quantify the anthropic energy flux of traffic impact on RST in the winter season. It indicated an RST increase by 1°C to 3 °C with respect to the absence of traffic. An additional work was undertaken so as to evaluate to which extent an accurate description of traffic might improve TEB numerical model when dedicated to RST simulations. Two approaches of traffic integration in this model were detailed and tested.
Geosci. Model Dev. Discuss., 8, 4737-4779, doi:10.5194/gmdd-8-4737-2015, 2015
The Geoengineering Model Intercomparison Project Phase 6 (GeoMIP6): simulation design and preliminary results
Geosci. Model Dev. Discuss., 8, 4697-4736, doi:10.5194/gmdd-8-4697-2015, 2015
ORCHIDEE-CROP (v0), a new process based Agro-Land Surface Model: model description and evaluation over Europe
Geosci. Model Dev. Discuss., 8, 4653-4696, doi:10.5194/gmdd-8-4653-2015, 2015
NCAR global model topography generation software for unstructured grids
Summary: This paper documents the NCAR global model topography generation software. The software generates elevation and related data for global atmospheric models. In the spirit of model development some exploratory simulations, varying the roughness of elevation, are presented.
Geosci. Model Dev. Discuss., 8, 4623-4651, doi:10.5194/gmdd-8-4623-2015, 2015
Sources of interannual yield variability in JULES-crop and implications for forcing with seasonal weather forecasts
Geosci. Model Dev. Discuss., 8, 4599-4621, doi:10.5194/gmdd-8-4599-2015, 2015
A sub-canopy structure for simulating oil palm in the Community Land Model: phenology, allocation and yield
Summary: A perennial oil palm plant function type is introduced and its specific multilayer structure, phenology, and carbon and nitrogen allocation functions are developed for modeling an important agricultural system in the tropics. Simulated LAI and yield were calibrated and validated with multiple sites in Sumatra, Indonesia. The new module allows exploring the effects of tropical land use change, from natural ecosystems to oil palm plantations on carbon, water and energy cycles and regional climate.
Geosci. Model Dev. Discuss., 8, 4545-4597, doi:10.5194/gmdd-8-4545-2015, 2015
SiSeRHMap v1.0: a simulator for mapped seismic response using a hybrid model
Summary: SiSeRHMap is a computer methodology for the mapped simulation of site seismic response (SSR) by means of a hybrid model. It combines physically based methods and adaptive and predictive numerical models that are solved in a layering GIS-geometric model. SiSeRHMap develops sets of different multispectral maps of site seismic response and other relating them, taking into account topography effects. Easy to use, SiSeRHMap seems to assure accuracy and robustness in the prediction performance.
Geosci. Model Dev. Discuss., 8, 4487-4544, doi:10.5194/gmdd-8-4487-2015, 2015
Assessment of valley cold pools and clouds in a very high resolution NWP model
Summary: The formation of cold air pools in valleys under stable conditions represents an important challenge for numerical weather prediction (NWP). In this study a two-month cold pool simulation is presented using a high resolution NWP model. Results are compared to observations and assumptions made in the cloud parametrization scheme about the sub-grid variability of humidity are shown to dominate model bias. Our results show that this is a key area for very high resolution modelling development.
Geosci. Model Dev. Discuss., 8, 4453-4486, doi:10.5194/gmdd-8-4453-2015, 2015
Metos3D: a marine ecosystem toolkit for optimization and simulation in 3-D – Simulation Package v0.2
Summary: In order to fundamentally tackle the problem of parameter identification for marine ecosystem models in 3-D, we introduced a general biogeochemical programming interface that fits into the optimization context. Moreover, we implemented a comprehensive parallel solver software for periodic steady-states that uses the interface to couple marine ecosystem models to a transport matrix driver. We validated the new implementation using a simple biogeochemical model.
Geosci. Model Dev. Discuss., 8, 4401-4451, doi:10.5194/gmdd-8-4401-2015, 2015
Importance of bitwise identical reproducibility in earth system modeling and status report
Geosci. Model Dev. Discuss., 8, 4375-4400, doi:10.5194/gmdd-8-4375-2015, 2015
Open-source modular solutions for flexural isostasy: gFlex v1.0
Summary: Earth's lithosphere bends beneath surface loads, such as ice, sediments, and mountain belts. The pattern of this bending, or flexural isostatic response, is a function of both the loads and the spatially-variable strength of the lithosphere. gFlex is an easy-to-use program to calculate flexural isostastic response, and may be used to better understand how ice sheets, glaciers, large lakes, sedimentary basins, volcanoes, and other surface loads interact with the solid Earth.
Geosci. Model Dev. Discuss., 8, 4245-4292, doi:10.5194/gmdd-8-4245-2015, 2015
Improved simulation of precipitation in the tropics using a modified BMJ scheme in WRF model
Summary: In this study the BMJ scheme, a convective adjustment scheme where temperature and humidity are relaxed towards reference profiles, as implemented in the WRF model version 3.3.1, is modified so that the precipitation produced by the model is in better agreement with that observed as given by the Tropical Rainfall Measuring Mission (TRMM) 3B42 dataset. The "modified BMJ" scheme gives a better representation of the observed rainfall for the whole tropics in both winter and summer seasons.
Geosci. Model Dev. Discuss., 8, 4019-4049, doi:10.5194/gmdd-8-4019-2015, 2015
Enhancement for bitwise identical reproducibility of Earth system modeling on the C-Coupler platform
Geosci. Model Dev. Discuss., 8, 2403-2435, doi:10.5194/gmdd-8-2403-2015, 2015