A size-composition resolved aerosol model for simulating the dynamics of externally mixed particles: SCRAM (v 1.0)
Summary: This article presents a Size-Composition Resolved Aerosol Model (SCRAM) for simulating the dynamics of externally-mixed atmospheric particles. The model is first validated by comparison with a reference solution and with results of simulations using internally-mixed particles. Then, the importance of representing the mixing state when modeling atmospheric aerosol concentrations is investigated in a box model simulation using data representative of air pollution in Greater Paris.
A simulation model to assess groundwater recharge over Europe's karst regions
Summary: We present a new approach to assess groundwater recharge over Europe's karst regions.
We use cluster analysis to subdivide Europe's karst regions into four typical karst landscapes.
We apply a new large-scale simulation model for karst recharge.
We estimate its parameters by a combination of a priori information and observations of soil moisture and evapotranspiration.
We show by independent observations of recharge that present large-scale models significantly under-estimate karst recharge.
A. Hartmann, T. Gleeson, R. Rosolem, F. Pianosi, Y. Wada, and T. Wagener Geosci. Model Dev. Discuss., 7, 7887-7935, 2014 AbstractDiscussion Paper (PDF, 5589 KB)Interactive Discussion (Open, 0 Comments)Manuscript under review for GMD
19 Nov 2014
An observation-constrained multi-physics RCM ensemble for simulating European mega-heatwaves
Summary: Climate models are often not evaluated against observations of past climate extremes, resulting in poor performance during for instance heatwave conditions. We use a regional climate model with different atmospheric physics schemes to simulate the heatwave events of 2003 in Western Europe and 2010 in Russia. The five best performing and diverse physics scheme combinations may be used in the future to perform heatwave analysis and to investigate the impact of climate change in summer in Europe.
Modelling climate change responses in tropical forests: similar productivity estimates across five models, but different mechanisms and responses
Summary: This study evaluates the capability of five vegetation models to simulate the response of forest productivity to changes in temperature and drought, using data collected from an Amazonian forest. This study concludes that model consistencies in the responses of net canopy carbon production to temperature and precipitation change were the result of inconsistent modelled leaf scale process responses and substantial variation in modelled leaf area responses.
L. Rowland, A. Harper, B. O. Christoffersen, D. R. Galbraith, H. M. A. Imbuzeiro, T. L. Powell, C. Doughty, N. M. Levine, Y. Malhi, S. R. Saleska, P. R. Moorcroft, P. Meir, and M. Williams Geosci. Model Dev. Discuss., 7, 7823-7859, 2014 AbstractDiscussion Paper (PDF, 1556 KB)Supplement (1042 KB)Interactive Discussion (Open, 0 Comments)Manuscript under review for GMD
19 Nov 2014
Verifications of the nonlinear numerical model and polarization relations of atmospheric acoustic-gravity waves
Summary: We performed high-resolution numerical simulations of nonlinear acoustic-gravity waves (AGWs) at altitudes 0 – 500 km and compared them with analytical polarization relations of linear AGW theory. After some transition time, t > te, the numbers of numerically simulated and analytical pairs of AGW parameters, which are equal with confidence 95%, are larger at altitudes 30 - 60 km and are smaller at t < te. The differences reveal circumstances, when numerical simulations of waves are required.
Tropospheric chemistry in the integrated forecasting system of ECMWF
Summary: We describe modules for atmospheric chemistry, wet and dry deposition and lightning NO production, which have been newly introduced in ECMWFs weather forecasting model. With that model we want to forecast global air pollution as part of the European Copernicus Atmosphere Monitoring Service. We show that the new model results compare as good or better with in-situ and satellite observations of ozone, CO, NO2, SO2 and formaldehyde than the previous model.
J. Flemming, V. Huijnen, J. Arteta, P. Bechtold, A. Beljaars, A.-M. Blechschmidt, B. Josse, M. Diamantakis, R. J. Engelen, A. Gaudel, A. Inness, L. Jones, E. Katragkou, V. Marecal, V.-H. Peuch, A. Richter, M. G. Schultz, O. Stein, and A. Tsikerdekis Geosci. Model Dev. Discuss., 7, 7733-7803, 2014 AbstractDiscussion Paper (PDF, 8171 KB)Supplement (95 KB)Interactive Discussion (Open, 0 Comments)Manuscript under review for GMDSpecial Issue
18 Nov 2014
Aerosol specification in single-column CAM5
Summary: In this study we explore the problem in running default CAM5-SCM, which initializes the aerosol to zero, and test three potential fixes in four different cloud regimes: DYCOMSRF02, MPACE-B, RICO, and ARM95. Stratiform cloud cases (DYCOMS RF02 and MPACE-B) were found to have a strong dependence on aerosol concentration, while convective cases (RICO and ARM95) were relatively insensitive to aerosol specification.
Summary: This paper provides a full GPU accelerated solution of mpiPOM. We design and implement several optimizing methods:
(i) computation optimization in a single GPU
(ii) communication optimization among multiple GPUs
(iii) I/O optimization between a hybrid GPU and CPU.
Our experimental results indicate that the performance of the gpuPOM on a workstation containing 4 GPUs is comparable to a powerful cluster with 408 CPU cores and it reduces the energy consumption by 6.8 times.
Development and evaluation of the Screening Trajectory Ozone Prediction System (STOPS, version 1.0)
Summary: This paper presents development and evaluation a hybrid Lagrangian-Eulerian modeling tool. In this tool, a small sub-domain follows a trajectory defined by the mean mixed-layer wind. The advantage of this tool compared to other Lagrangian models is its capability of utilizing realistic boundary conditions that change with space and time as well as a detailed treatment of chemical reactions.
Reduction of predictive uncertainty in estimating irrigation water requirement through multi-model ensembles and ensemble averaging
Summary: Irrigation agriculture is required to sustain yields that allow feeding the world population. A robust assessment of irrigation requirement (IRR) relies on a sound quantification of evapotranspiration (ET). We prepared a multi-model ensemble considering several ET methods and investigate uncertainties in simulating IRR. More generally, we provide an example of the value of investigating the uncertainty in models that may be used to inform policy-making and to elaborate best management practices.
S. Multsch, J.-F. Exbrayat, M. Kirby, N. R. Viney, H.-G. Frede, and L. Breuer Geosci. Model Dev. Discuss., 7, 7525-7558, 2014 AbstractDiscussion Paper (PDF, 1366 KB)Interactive Discussion (Open, 0 Comments)Manuscript under review for GMD
10 Nov 2014
Development of a grid-independent GEOS-chem chemical transport model as an atmospheric chemistry module for Earth System Models
Summary: This paper presents results from the modularization of the GEOS-Chem Chemical Transport Model, and its coupling as the chemical operator within the NASA-GMAO GEOS-5 Earth System Model (ESM). The key findings are that chemistry within the modular GEOS-Chem system shows consistent, high strong-scaling properties across the range of distributed processors, transport is the limiting component prohibiting efficient scalability, and GEOS-Chem is able to generate suitable chemical results in an ESM.
M. S. Long, R. Yantosca, J. E. Nielsen, C. A. Keller, A. da Silva, M. P. Sulprizio, S. Pawson, and D. J. Jacob Geosci. Model Dev. Discuss., 7, 7505-7524, 2014 AbstractDiscussion Paper (PDF, 2955 KB)Interactive Discussion (Open, 0 Comments)Manuscript under review for GMD
10 Nov 2014
Carbon isotopes in the ocean model of the Community Earth System Model (CESM1)
Summary: Carbon isotopes have been added to the ocean model of the Community Earth System Model version 1 (CESM1). This paper describes the details of how the abiotic 14C tracer and the biotic 13C and 14C tracers were added to the existing ocean model of the CESM. In addition, it shows first results of the new model features compared to observational data for the 1990s.
A. Jahn, K. Lindsay, X. Giraud, N. Gruber, B. L. Otto-Bliesner, Z. Liu, and E. C. Brady Geosci. Model Dev. Discuss., 7, 7461-7503, 2014 AbstractDiscussion Paper (PDF, 4005 KB)Interactive Discussion (Open, 0 Comments)Manuscript under review for GMD
06 Nov 2014
An approach to enhance pnetCDF performance in environmental modeling applications
Thermo-hydro-mechanical processes in fractured rock formations during glacial advance
Summary: The paper examines the coupled thermo-hydro-mechanical (THM) processes that develop in a fractured rock region within a fluid-saturated rock mass due to loads imposed by an advancing glacier. This scenario needs to be examined in order to assess the suitability of potential sites for the location of deep geologic repositories for the storage of high-level nuclear waste. The THM processes are examined using a computational multiphysics approach.
EDDA: integrated simulation of debris flow erosion, deposition and property changes
Summary: A new numerical model, EDDA, is developed for simulating debris-flow erosion, deposition, and associated changes in debris mass, properties and topography. A variable time step algorithm is adopted to assure both numerical accuracy and computational efficiency. The performance of the model has been verified through four numerical tests and a large-scale case study. EDDA can be a powerful tool for debris-flow risk assessment in a large area and real-time landslide warning.
An integrated user-friendly ArcMAP tool for bivariate statistical modeling in geoscience applications
Summary: The main contributions of this manuscript are:
• A novel an easy to use ArcMap tool is proposed for bivariate statistical analysis model implementation.
• The developed tool facilitated and speed up the BSA modeling process of frequency ratio, weights-of-evidence, and evidential belief function.
• This tool classifies the variables based on the acquired weights automatically.
• All three methods were tested on a study area and landslide susceptibility maps were produced.
Technical challenges and solutions in representing lakes when using WRF in downscaling applications
M. S. Mallard, C. G. Nolte, T. L. Spero, O. R. Bullock, K. Alapaty, J. A. Herwehe, J. Gula, and J. H. Bowden Geosci. Model Dev. Discuss., 7, 7121-7150, 2014 AbstractDiscussion Paper (PDF, 639 KB)Interactive Discussion (Open, 0 Comments)Manuscript under review for GMD
27 Oct 2014
A simple object-oriented and open source model for scientific and policy analyses of the global carbon cycle – Hector v0.1
Summary: Simple climate models play an integral role in policy and scientific communities. Hector v0.1 is an open source, object-oriented, simple global climate carbon-cycle model. It runs essentially instantaneously while still representing the most critical earth system processes. Hector reproduces the global historical trends of atmospheric [CO2] and surface temperatures and simulates all four Representative Concentration Pathways.
C. A. Hartin, P. Patel, A. Schwarber, R. P. Link, and B. P. Bond-Lamberty Geosci. Model Dev. Discuss., 7, 7075-7119, 2014 AbstractDiscussion Paper (PDF, 2188 KB)Interactive Discussion (Open, 0 Comments)Manuscript under review for GMD
24 Oct 2014
14C-age tracers in global ocean circulation models
Summary: The natural abundance of 14C in CO2 dissolved in seawater is often used to evaluate circulation and age in the ocean and in ocean models. We study limitations of using natural 14C to determine the time elapsed since water had contact with the atmosphere. We find that, globally, bulk 14C-age is dominated by two equally important components, (1) the time component of circulation and (2) the “preformed 14C-age”. Considering preformed 14C-age is critical for a assessment of circulation in models.
A user-friendly forest model with a multiplicative mathematical structure: a Bayesian approach to calibration
M. Bagnara, M. Van Oijen, D. Cameron, D. Gianelle, F. Magnani, and M. Sottocornola Geosci. Model Dev. Discuss., 7, 6997-7031, 2014 AbstractDiscussion Paper (PDF, 5515 KB)Interactive Discussion (Open, 1 Comment)Manuscript under review for GMD
22 Oct 2014
GNAQPMS-Hg v1.0, a global nested atmospheric mercury transport model: model description, evaluation and application to trans-boundary transport of Chinese anthropogenic emissions
Summary: 1.A new global nested atmospheric mercury transport model was developed and introduced.
2.Model performance was found significantly better in North America and Europe than in East Asia.
3.Nested simulation has been conducted in East Asia and shows improved skill at capturing the high spatial variability of Hg concentrations and deposition.
4.The trans-boundary transport of Chinese primary anthropogenic mercury emissions was quantified for the first time.
Global sensitivity analysis, probabilistic calibration, and predictive assessment for the Data Assimilation Linked Ecosystem Carbon model
Summary: In this paper we propose a probabilistic framework for an uncertainty quantification study of a Carbon cycle model. We study model parameters via Global Sensitivity Analysis and employ a Bayesian approach to
calibrate these parameters using net ecosystem exchange observations at the Harvard Forest site. Overall, this study leads to a 40% improvement in the predictive skill of the Carbon cycle model and highlights the importance of considering parameter correlations as informed by the data.
C. Safta, D. Ricciuto, K. Sargsyan, B. Debusschere, H. N. Najm, M. Williams, and P. Thornton Geosci. Model Dev. Discuss., 7, 6893-6948, 2014 AbstractDiscussion Paper (PDF, 2971 KB)Interactive Discussion (Open, 1 Comment)Manuscript under review for GMD
15 Oct 2014
A test of an optimal stomatal conductance scheme within the CABLE Land Surface Model
Summary: Stomatal conductance (gs) affects the fluxes of carbon, energy and water between the vegetated land surface and the atmosphere. We test an implementation of an optimal stomatal conductance model within the CABLE land surface model (LSM). The new implementation resulted in a large reduction in the annual fluxes of transpiration across evergreen needleleaf, tundra and C4 grass regions. Optimisation theory can yield a simple and tractable approach to predicting gs in LSMs.
M. G. De Kauwe, J. Kala, Y.-S. Lin, A. J. Pitman, B. E. Medlyn, R. A. Duursma, G. Abramowitz, Y.-P. Wang, and D. G. Miralles Geosci. Model Dev. Discuss., 7, 6845-6891, 2014 AbstractDiscussion Paper (PDF, 5076 KB)Interactive Discussion (Open, 0 Comments)Manuscript under review for GMD
15 Oct 2014
IceChrono v1: a probabilistic model to compute a common and optimal chronology for several ice cores
Summary: This manuscript describes a probabilistic model which aims at optimizing the chronology of ice cores by combining different sources of information.
JULES-crop: a parametrisation of crops in the Joint UK Land Environment Simulator
T. Osborne, J. Gornall, J. Hooker, K. Williams, A. Wiltshire, R. Betts, and T. Wheeler Geosci. Model Dev. Discuss., 7, 6773-6809, 2014 AbstractDiscussion Paper (PDF, 3392 KB)Interactive Discussion (Open, 2 Comments)Manuscript under review for GMD
NEMOTAM: tangent and adjoint models for the ocean modelling platform NEMO
Summary: This paper presents tha tangent and adjoint models for the NEMO ocean modelling framework. They are useful tools for sensitivity and stability analysis. The implementation choices and the validation of the code is presented as well as a selection of applications.
Hindcast regional climate simulations within EURO-CORDEX: evaluation of a WRF multi-physics ensemble
E. Katragkou, M. García-Díez, R. Vautard, S. Sobolowski, P. Zanis, G. Alexandri, R. M. Cardoso, A. Colette, J. Fernández, A. Gobiet, K. Goergen, T. Karacostas, S. Knist, S. Mayer, P. M. M. Soares, I. Pytharoulis, I. Tegoulias, A. Tsikerdekis, and D. Jacob Geosci. Model Dev. Discuss., 7, 6629-6675, 2014 AbstractDiscussion Paper (PDF, 6027 KB)Supplement (1765 KB)Interactive Discussion (Open, 1 Comment)Manuscript under review for GMD
02 Oct 2014
Quantitative evaluation of ozone and selected climate parameters in a set of EMAC simulations
A Global Carbon Assimilation System using a modified EnKF assimilation method
S. Zhang, X. Zheng, Z. Chen, B. Dan, J. M. Chen, X. Yi, L. Wang, and G. Wu Geosci. Model Dev. Discuss., 7, 6519-6547, 2014 AbstractDiscussion Paper (PDF, 3090 KB)Interactive Discussion (Open, 1 Comment)Manuscript under review for GMD
01 Oct 2014
The impact of periodization methods on the kinetic energy spectra for limited-area numerical weather prediction models
Characterising Brazilian biomass burning emissions using WRF-Chem with MOSAIC sectional aerosol
S. Archer-Nicholls, D. Lowe, E. Darbyshire, W. T. Morgan, M. M. Bela, G. Pereira, J. Trembath, J. W. Kaiser, K. M. Longo, S. R. Freitas, H. Coe, and G. McFiggans Geosci. Model Dev. Discuss., 7, 6061-6131, 2014 AbstractDiscussion Paper (PDF, 5877 KB)Supplement (21509 KB)Interactive Discussion (Open, 5 Comments)Manuscript under review for GMD
17 Sep 2014
Integration of Geographic Information System frameworks into domain discretisation and meshing processes for geophysical models
A sparse reconstruction method for the estimation of multiresolution emission fields via atmospheric inversion
J. Ray, J. Lee, V. Yadav, S. Lefantzi, A. M. Michalak, and B. van Bloemen Waanders Geosci. Model Dev. Discuss., 7, 5623-5659, 2014 AbstractDiscussion Paper (PDF, 912 KB)Interactive Discussion (Open, 2 Comments)Manuscript under review for GMD
20 Aug 2014
Assimilation of surface NO2 and O3 observations into the SILAM chemistry transport model
IGCM4: a fast, parallel and flexible intermediate climate model
M. Joshi, M. Stringer, K. van der Wiel, A. O'Callaghan, and S. Fueglistaler Geosci. Model Dev. Discuss., 7, 5517-5545, 2014 AbstractDiscussion Paper (PDF, 1553 KB)Interactive Discussion (Open, 1 Comment)Manuscript under review for GMD
15 Aug 2014
Mapping of satellite Earth observations using moving window block kriging