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
A new multiscale air quality transport model (Fluidity, 4.1.9) using fully unstructured anisotropic adaptive mesh technology
Summary: A new anisotropic hr-adaptive mesh technique has been applied to modelling of multiscale transport phenomena. Over existing air quality models typically based on static-structured grids using a locally nesting technique, the advantage of the anisotropic hr-adaptive model has the ability to adapt the mesh according to the evolving pollutant distribution and flow features. To illustrate its capability, comparisons have been made between the results obtained using adaptive and uniform meshes.
Geosci. Model Dev. Discuss., 8, 4337-4374, doi:10.5194/gmdd-8-4337-2015, 2015
Ice-sheet configuration in the CMIP5/PMIP3 Last Glacial Maximum experiments
Summary: We describe the creation of boundary conditions related to the presence of ice sheets, including ice sheet extent and height, ice shelf extent, and the distribution and altitude of ice-free land, at the Last Glacial Maximum (LGM) for use in LGM experiments conducted as part of the Coupled Modelling Intercomparison Project (CMIP5) and Palaeoclimate Modelling Intercomparison Project (PMIP3). The difference of the ice sheet boundary conditions as well as the climate response to them are discussed.
Geosci. Model Dev. Discuss., 8, 4293-4336, doi:10.5194/gmdd-8-4293-2015, 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
A semi-Lagrangian advection scheme for radioactive tracers in a regional spectral model
Summary: In this study, the non-iteration dimensional-split semi-Lagrangian (NDSL) advection scheme is applied to the National Centers for Environmental Prediction (NCEP) regional spectral model (RSM) to alleviate the Gibbs phenomenon. The model runs for the Fukushima accident case study suggest that the NDSL can successfully advect radioactive tracers (iodine-131 and cesium-137) without noise from the Gibbs phenomenon.
Geosci. Model Dev. Discuss., 8, 4221-4243, doi:10.5194/gmdd-8-4221-2015, 2015
Treatment of non-ideality in the multiphase model SPACCIM – Part 1: Model development
Summary: The present paper was aimed at the further development of SPACCIM to treat both complex multiphase chemistry and phase transfer processes considering newly non-ideality properties of concentrated solutions. Model studies showed the applicability of the new kinetic model approach for complex aerosol mixtures and detailed chemical mechanisms. Simulations have implied that the treatment of non-ideality should be mandatory for modeling multiphase chemical processes in deliquesced particles.
Geosci. Model Dev. Discuss., 8, 4155-4219, doi:10.5194/gmdd-8-4155-2015, 2015
Integration of nitrogen dynamics into the Noah-MP land model v1.1 for climate and environmental predictions
Summary: A terrestrial nitrogen dynamics model is integrated into Noah-MP. The new model performs well in capturing the major nitrogen state/flux variables (e.g., soil nitrate and nitrate leaching). The addition of nitrogen dynamics improves the modeling of the carbon and water cycles (e.g., net primary productivity and evapotranspiration). This improvement advances the capability of Noah-MP to simultaneously predict weather and water quality.
Geosci. Model Dev. Discuss., 8, 4113-4153, doi:10.5194/gmdd-8-4113-2015, 2015
A fully coupled Atmosphere–Ocean Wave modeling system (WEW) for the Mediterranean Sea: interactions and sensitivity to the resolved scales and mechanisms
Summary: This paper includes the entire steps and processes to develop a two-way fully coupled atmosphere-ocean wave model (WEW) aiming a better description and understanding of the exchange processes near the ocean surface. WEW offers a more realistic representation of the extreme weather and sea state events over the ocean bodies and finally leads in an overall improved simulations.
Geosci. Model Dev. Discuss., 8, 4075-4112, doi:10.5194/gmdd-8-4075-2015, 2015
Photolysis rates in correlated overlapping cloud fields: Cloud-J 7.3
Geosci. Model Dev. Discuss., 8, 4051-4073, doi:10.5194/gmdd-8-4051-2015, 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
S4CAST v2.0: sea surface temperature based statistical seasonal forecast model
Geosci. Model Dev. Discuss., 8, 3971-4018, doi:10.5194/gmdd-8-3971-2015, 2015
A global empirical system for probabilistic seasonal climate prediction
Summary: Our paper reports on a simple regression-based system for producing probabilistic forecasts of seasonal climate. We discuss the physical motivation behind the statistical relationships underpinning our empirical model and provide a validation of hindcasts produced for the last half century. The generation of probabilistic forecasts on a global scale along with the use of the long-term trend as a source of skill constitutes a novel approach to empirical forecasting of seasonal climate.
Geosci. Model Dev. Discuss., 8, 3941-3970, doi:10.5194/gmdd-8-3941-2015, 2015
Updating sea spray aerosol emissions in the Community Multiscale Air Quality (CMAQ) model version 5.0.2
Geosci. Model Dev. Discuss., 8, 3905-3939, doi:10.5194/gmdd-8-3905-2015, 2015
Evaluation of the Community Multiscale Air Quality (CMAQ) model v5.0 against size-resolved measurements of inorganic particle composition across sites in North America
Summary: This study is the most comprehensive evaluation of CMAQ inorganic aerosol size-composition distributions conducted to date. We compare two methods of inferring PM2.5 concentrations from the model: (1) based on the sum of the masses in the fine aerosol modes, as is most commonly done in CMAQ model evaluation; and (2) computed using the simulated size distributions. Differences are generally less than 1microgram/m3, and are largest over the eastern United States during the summer.
Geosci. Model Dev. Discuss., 8, 3861-3904, doi:10.5194/gmdd-8-3861-2015, 2015
A new ensemble-based consistency test for the Community Earth System Model
Summary: Climate simulations codes are especially complex, and their on-going state of development requires frequent software quality assurance to both preserve code quality and instill model confidence. To formalize and simplify this previously subjective and expensive process, we have developed a new tool for evaluating climate consistency. The tool has proven its utility in detecting errors in software and hardware environments and providing rapid feedback to model developers.
Geosci. Model Dev. Discuss., 8, 3823-3859, doi:10.5194/gmdd-8-3823-2015, 2015
An automatic and effective parameter optimization method for model tuning
Summary: A “three-step” methodology is proposed to effectively obtain the optimum combination of some key parameters in cloud and convective parameterizations according to a comprehensive objective evaluation metrics. The optimal results improve the metrics performance by 9%. A software framework can automatically execute any part of the “three-step” calibration strategy. The proposed methodology and framework can be easily applied to other GCMs to speed up the model development process.
Geosci. Model Dev. Discuss., 8, 3791-3822, doi:10.5194/gmdd-8-3791-2015, 2015
ECCO version 4: an integrated framework for non-linear inverse modeling and global ocean state estimation
Summary: The ECCO v4 nonlinear inverse modeling framework and its reference solution are made publicly available. The inverse estimate of ocean physics and atmospheric forcing yields a dynamically consistent and global state estimate without unidentified sources of heat and salt that closely fits in-situ and satellite data. Any user can reproduce it accurately. Parametric and external model uncertainties are of comparable magnitudes and generally exceed structural model uncertainties.
Geosci. Model Dev. Discuss., 8, 3653-3743, doi:10.5194/gmdd-8-3653-2015, 2015
Using satellite-based estimates of evapotranspiration and groundwater changes to determine anthropogenic water fluxes in land surface models
Summary: 1. Current land surface models (LSMs) poorly represent irrigation impacts on regional hydrology. 2. Approaches to include irrigation in LSMs are based on either potentially outdated irrigation inventory data or soil moisture curves that are not constrained by regional water balances. 3. We use satellite remote sensing of actual ET and groundwater depletion to develop recent estimates of regional irrigation data. 4. Remote-sensing parameterizations of irrigation improve model performance.
Geosci. Model Dev. Discuss., 8, 3565-3592, doi:10.5194/gmdd-8-3565-2015, 2015
The Louvain-la-Neuve sea ice model LIM3.5: global and regional capabilities
Geosci. Model Dev. Discuss., 8, 3403-3441, doi:10.5194/gmdd-8-3403-2015, 2015
Using field observations to inform thermal hydrology models of permafrost dynamics with ATS (v0.83)
Summary: Development and calibration of a process-rich model representation of thaw-depth dynamics in Arctic tundra is presented. Improved understanding of polygonal tundra thermal hydrology processes, of thermal conduction, surface and subsurface saturation and snowpack dynamics is gained by using measured field data to calibrate and refine model structure. The refined model is then used identify future data needs and observational studies.
Geosci. Model Dev. Discuss., 8, 3235-3292, doi:10.5194/gmdd-8-3235-2015, 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