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Geoscientific Model Development An interactive open-access journal of the European Geosciences Union

Scheduled special issues

The following special issues are scheduled for publication in GMD:

BACCHUS – Impact of Biogenic versus Anthropogenic emissions on Clouds and Climate: towards a Holistic UnderStanding (ACP/AMT/GMD inter-journal SI)
14 Jun 2017–31 Dec 2018 | Coordinator: U. Lohmann | Papers are handled by GMD topical editors | Information

BACCHUS is a European FP7 Collaborative Project aiming at quantifying key processes and feedbacks that control aerosol–cloud interactions by combining advanced measurement techniques of cloud and aerosol properties with emphasis on ice nucleating particles and the ice phase in clouds with state-of-the-art numerical modelling. It investigates the importance of biogenic versus anthropogenic emissions for aerosol–cloud interactions in regions that are key regulators of Earth's climate (Amazonian rainforest) or are regarded as tipping elements in the climate system (Arctic). BACCHUS advances the understanding of biosphere aerosol–cloud–climate feedbacks that occur via emission and transformation of biogenic volatile organic compounds, primary biological aerosols, secondary organic aerosols, and dust. New fundamental understanding gained during BACCHUS will be incorporated into Earth system models through new or improved parameterizations of emissions, aerosol and cloud processes, and properties, which will lead to a reduction in the uncertainty of future climate projections. A unique database linking long-term observations and field campaign data of ice nucleating particles and observed cloud microphysical properties has been generated.

The BACCHUS special issue will be simultaneously presented in the ACP, AMT, and GMD journals and is open for all submissions acknowledging the BACCHUS project. BACCHUS is a collaborative project of 21 partner institutions: ETH Zurich, University of Helsinki, Paul Scherrer Institute, Max Planck Society (MPI-M, MPI-C), University of Oxford, University of Oslo, Finnish Meteorological Institute, University of Leeds, University of Manchester, Leibniz Institute for Tropospheric Research, Goethe University Frankfurt, the University of Crete, National Research Council of Italy – Institute of Atmospheric Sciences and Climate, National University of Ireland Galway, Institute for Nuclear Research and Nuclear Energy, Hebrew University of Jerusalem, National Center for Scientific Research (France), Karlsruhe Institute of Technology, Cyprus Institute, Cyprus University of Technology, and University of Gothenburg. The project is funded by the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 603445.

The Model Intercomparison Project on the climatic response to Volcanic forcing (VolMIP) (ESD/ACP/CP/GMD inter-journal SI)
15 May 2017–30 Apr 2019 | Coordinators: C. Timmreck, M. Khodri, and D. Zanchettin | Papers are handled by GMD topical editors | Information

Volcanic eruptions are one of the major natural factors influencing climate variability at interannual to multidecadal timescales. However, simulating volcanically forced climate variability is a challenging task for climate models and one of the major uncertainties in near-term climate predictions. The Model Intercomparison Project on the climatic response to Volcanic forcing (VolMIP) is an endorsed contribution to the sixth phase of the Coupled Model Intercomparison Project. This multi-journal special issue on VolMIP aims at collecting relevant research results obtained within the VolMIP framework, and specifically concerning different aspects of the radiative and dynamical climatic response to volcanic forcing, detailed description of effects of different implementation of volcanic forcing in current climate models, aspects concerning the dynamical and chemical atmospheric response to volcanic aerosols simulated by global aerosol models, and comparison between reconstructed and simulated climate evolution after major eruptions. Articles in the special issue should contain the following statement: "This article is part of the special issue "The Model Intercomparison Project on the climatic response to Volcanic forcing (VolMIP) (ESD/GMD/ACP/CP inter-journal SI)". It does not belong to a conference."

The Transport Matrix Method (TMM) for ocean biogeochemical simulations
15 Feb 2017–indefinite | Coordinator: S. Khatiwala | Papers are handled by GMD topical editors | Information

Scope: The Transport Matrix Method (TMM) is a computationally efficient "offline" scheme for simulation of ocean biogeochemical tracers. The TMM essentially encapsulates the circulation of any ocean model, including sub-grid-scale parameterizations, as a sparse matrix, and advection-diffusion as a sequence of sparse matrix-vector products that can be efficiently carried out on modern distributed-memory computers. Simulations carried out with the TMM can potentially be orders of magnitude faster than the underlying ocean circulation model. The flexible architecture of the TMM framework also allows "mixing and matching" of circulations and biogeochemical models. The TMM code, various biogeochemical models, and transport matrices from different ocean models are freely available to download from

The aim of this Special Issue is to bring together under one roof papers using the TMM as the underlying simulation method. This can range from manuscripts documenting various technical aspects of the TMM framework to those describing new biogeochemical models/parameterizations and their application.

Paleoclimate Modelling Intercomparison Project phase 4 (PMIP4) (CP/GMD inter-journal SI)
10 Jan 2017–31 Dec 2018 | Coordinator: M. Kageyama | Papers are handled by GMD topical editors | Information

The Paleoclimate Modelling Intercomparison Project (PMIP) has been set up to provide a mechanism for coordinating paleoclimate modelling and model evaluation activities, to understand the mechanisms of climate change and the role of climate feedbacks in these changes. PMIP is now in its fourth phase: PMIP4. Five PMIP4 experiments have been proposed within the framework of the CMIP6 exercise. Other periods and sensitivity experiments are also planned to assess climate sensitivity, changes in hydrology, long-term trends and interannual to millennium variability. This special issue is devoted to the description of the design of the PMIP4 experiments, of data syntheses to which model results can be compared, and to papers analysing single or multi-model results from PMIP4 and CMIP6 experiments. Papers can either be submitted to GMD (model and simulation descriptions, data syntheses in support of the experimental design or of model-data comparisons) or CP (in-depth analyses, multi-model analyses, model-data comparisons).

The Lagrangian particle dispersion model FLEXPART
25 Oct 2016–indefinite | Coordinator: I. Pisso | Papers are handled by GMD topical editors | Information

The Lagrangian particle dispersion model FLEXPART was originally designed for calculating the long-range and mesoscale dispersion of air pollutants from point sources, such as after an accident in a nuclear power plant. The model has now evolved into a comprehensive tool for atmospheric transport modelling and analysis. Its application fields are extended to a range of atmospheric transport processes for both atmospheric gases and aerosols, e.g. greenhouse gases, ozone depletion substances, short-lived climate forces like black carbon, volcanic ash and gases as well as studies of the water cycle. It supports ECMWF, NCEP, mesoscale (WRF) and climate (NorESM, CAM) wind fields in both forward and backwards modes. FLEXTPART is open source (

JULES-crop: a parameterisation of crops in the JULES land surface model
19 Oct 2016–indefinite | Coordinator: K. Williams | Papers are handled by GMD topical editors | Information

The Joint UK Land Environment Simulator (JULES) is a process-based, community model that simulates the fluxes of carbon, water, energy and momentum between the land surface and the atmosphere. JULES-crop is a parameterisation of crops within JULES which was developed with the dual aim of being able to simulate the impact of weather and climate on crop productivity and the impact that croplands have on weather and climate. This ongoing special issue collects together papers on model development, evaluation and application of JULES-crop.

Dynamical Core Model Intercomparison Project 2016
01 Jun 2016–31 Aug 2017 | Coordinator: P. A. Ullrich | Papers are handled by GMD topical editors | Information

The purpose of this special issue is to collect articles related to the Dynamical Core Model Intercomparison Project 2016 and provide a comprehensive review of modern practices for dynamical core model design. Further information on the DCMIP 2016 can be found here.

Changing Permafrost in the Arctic and its Global Effects in the 21st Century (PAGE21) (BG/TC/GMD/ESSD inter-journal SI)
01 Jan 2016–31 Dec 2017 | Papers are handled by GMD topical editors | Information

Permafrost is defined as ground that remains continuously at or below 0°C for at least two consecutive years; some 24% of the land surface in the Northern Hemisphere is classified as permafrost. In the northern high latitudes, strong warming has been observed over the recent decades, and climate models project strong future warming. A projected decline in the extent of permafrost will have a major impact on the Earth system, affecting global climate through the mobilization of carbon and nitrogen stored in permafrost. This special issue invites results of the large-scale European project PAGE21 with the aim to quantify the vulnerability of permafrost environments to a changing global climate, and to investigate the feedback mechanisms associated with increasing greenhouse gas emissions from permafrost zones. The focus is on (i) the combination of field mapping and measurements of permafrost landforms, ground ice content, processes, pools, and fluxes, with remote sensing data and global climate models at local, regional, and pan-Arctic scales, as well as (ii) advancing our understanding of permafrost processes at multiple scales, resulting in improvements in global numerical permafrost modeling.

Chemistry–Climate Modelling Initiative (CCMI) (ACP/AMT/ESSD/GMD inter-journal SI)
23 Oct 2015–30 Sep 2018 | Papers are handled by GMD topical editors | Information

IGAC/SPARC CCMI ( consists of a wide range of researchers, including chemistry-climate modelers, observationalists, and data analysts who are investigating the historical and projected evolution of stratospheric and tropospheric composition and chemistry, including the links between those domains, and the feedbacks with the physical climate. A current CCMI activity is a series of hindcast model simulations in support of upcoming ozone and climate assessments. The goal is to quantify how well the models can reproduce the past behavior (climatology, trends and interannual variability) of tropospheric and stratospheric ozone, other oxidants, and more generally chemistry-climate interactions, as well as to understand processes that govern these interactions. An emphasis is placed on observational based evaluation of model output, including model processes. A future CCMI activity will be to analyze projections of the future evolution of tropospheric and stratospheric ozone.

Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) (ACP/BG/AMT/GMD/GI inter-journal SI)
01 Jun 2015–31 May 2018 | Papers are handled by GMD topical editors | Information

Observations and modelling of the Green Ocean Amazon (GoAmazon2014/5): the GoAmazon2014/5 campaign sought to quantify and understand how aerosol and cloud life cycles in a particularly clean background in the tropics were influenced by pollutant outflow from a large tropical city. The project addressed the susceptibility of cloud–aerosol–precipitation interactions to present-day and future pollution in the tropics. The experiment took place in central Amazonia from 1 January 2014 to 31 December 2015, including intensive operating periods and aircraft in the wet and dry seasons of 2014.

Model infrastructure integration and interoperability (MI3)
01 Jan 2015–indefinite | Coordinator: R. Dunlap | Papers are handled by GMD topical editors | Information

Geoscience model infrastructure provides architecture and services for building physics-based numerical models and combining multiple models into a coupled system. Examples of model infrastructure are software libraries and frameworks that provide data structures and functions for parallel data transfer and grid interpolation, define a common interface for model components, manage a model's control flow, abstract details of parallel programming, or provide supporting capabilities such as configuration management and file I/O. The special issue of GMD is dedicated to exploring all aspects of model infrastructure integration and interoperability. Model infrastructure integration is the software engineering process of adopting an infrastructure package into a numerical model's codebase, to address new scientific requirements, enable interoperability with other models, or to improve a model's performance. Model infrastructure interoperability is required whenever multiple infrastructure packages must interact in some way in a coupled system, for example, to couple model components that originate from different scientific communities into a single cohesive system. Topics of interest for this issue include but are not limited to the following: the design and implementation of geoscience model infrastructure software; experience reports on integrating infrastructure into models; modelling systems that span scientific communities; framework interoperability, metadata and semantic mediation; performance on emerging hardware platforms; configuration and build management; and tools that support infrastructure integration, code refactoring, verification, or debugging.

The SimSphere Land Biosphere Model
01 Feb 2015–indefinite | Coordinator: G. P. Petropoulos | Papers are handled by GMD topical editors | Information

SimSphere is a one-dimensional soil–vegetation–atmosphere transfer model devoted to the study of land surface interactions of the Earth's system. Since its early development, the model has become highly variable in its application use.

Apart from its use as an educational tool at several universities worldwide, SimSphere is used in a number of research studies related to the examination of hypothetical scenarios examining land surface processes and feedbacks. It is also used synergistically with Earth observation (EO) data to retrieve spatiotemporal estimates of energy fluxes and surface soil moisture, involving exploration studies on the development of related operational products.

This special issue hosts contributions concerned with descriptions of further upgrades of SimSphere or its exploitation in any way. It comprises articles on model developments or applications involving the model; this includes – but is not limited to – studies exploring hypothetical scenario examination, model validation, sensitivity analysis and synergies of it with EO data.

Coupled Model Intercomparison Project Phase 6 (CMIP6) – Experimental Design and Organization
01 Dec 2015–31 Dec 2017 | Coordinator: V. Eyring | Papers are handled by GMD topical editors | Information

The Coupled Model Intercomparison Project (CMIP) has been a major, very successful endeavor of the climate community for understanding past climate changes and for making projections and uncertainty estimates of the future in a multi-model framework. CMIP has developed in phases, with the simulations of the fifth phase, CMIP5, mostly completed. This special issue describes the new design and organization of CMIP and the suite of experiments of its next phase (i.e., CMIP6) in a series of invited contributions. The description of the experiments and forcing data sets presented here define CMIP6 in detail. The papers provide the required information to produce a consistent set of climate model simulations that can be scientifically exploited to address the three broad scientific questions of CMIP6: (1) How does the Earth system respond to forcing?, (2) What are the origins and consequences of systematic model biases?, and (3) How can we assess future climate changes given climate variability, predictability and uncertainties in scenarios? The special issue will include an overview paper on the CMIP6 design and organization, contributions from CMIP6-endorsed MIPs and descriptions of the forcing data sets.

The Modular Earth Submodel System (MESSy) (ACP/GMD inter-journal SI)
08 Oct 2014–indefinite | Coordinator: P. Jöckel | Papers are handled by GMD topical editors | Information

The Modular Earth Submodel System (MESSy) is a multi-institutional project providing a strategy and the software for developing Earth System Models (ESMs) with highly flexible complexity.

The strategy follows a bottom-up approach, meaning that the various processes and diagnostic tools are implemented as so-called submodels, which are technically independent of each other and strictly separated from the underlying technical model infrastructure, such as memory management, input/output, flow-control, etc.

The MESSy software provides generalized interfaces for the standardized control and interconnection (coupling) of these submodels.

The present time-unlimited Special Issue hosts scientific and technical documentation and evaluation manuscripts concerned with the Modular Earth Submodel System and the models build upon it. Moreover, it comprises manuscripts about scientific applications involving these models.

The Geoengineering Model Intercomparison Project (GeoMIP): Simulations of solar radiation reduction methods
(ACP/GMD inter-journal SI)

02 Oct 2014–30 Sep 2017 | Coordinator: U. Lohmann, N. Vaughan, L. M. Russell, B. Kravitz, and H. Wang | Papers are handled by GMD topical editors | Information

The Geoengineering Model Intercomparison Project (GeoMIP) has been highly successful in identifying robust climate model response to various geoengineering scenarios. There are currently seven core GeoMIP simulations, with another four submitted as GeoMIP's contribution to CMIP6. These experiments evaluate model response to various forms of geoengineering, focusing on solar dimming, stratospheric sulfate aerosol injections, marine cloud brightening via sea spray, and cirrus cloud thinning. In this special issue, we examine results from these simulations that have been conducted by 15 climate modeling centers from around the world. The results presented here provide a key source of information about the range of potential climate effects from geoengineering, any possible unintended side effects that geoengineering may cause, and the efficacy of geoengineering as a response to climate change. These simulations also reveal fundamental climate responses to radiative forcing, illuminating various feedback processes and interactions between different components of climate models.

Data assimilation in carbon/biogeochemical cycles: consistent assimilation of multiple data streams
(BG/ACP/GMD inter-journal SI)

01 Jan 2015–30 Apr 2017 | Coordinator: M. Scholze | Papers are handled by GMD topical editors

The community version of the Weather Research and Forecasting Model as it is coupled with Chemistry (WRF-Chem)
(GMD/ACP inter-journal SI)

20 Dec 2013–31 Dec 2018 | Coordinator: G. Grell | Papers are handled by GMD topical editors | Information

The Weather Research and Forecast community modelling system coupled with Chemistry (WRF-Chem) provides the capability to simulate and forecast weather, trace gases, and aerosols from hemispheric to urban scales. WRF-Chem is a community model. WRF-Chem is an online modelling system which includes the treatment of the aerosol direct and indirect effect. It incorporates many choices for gas phase chemistry and aerosols with degrees of complexity that are suitable for forecasting and research applications. Due to its versatility WRF-Chem is attracting a large user and developer community world-wide. The present time-unlimited Special Issue hosts scientific technical documentation and evaluation manuscripts concerned with the community version of WRF-Chem.

GA/GL: Description of the Met Office Unified Model Global Atmosphere and JULES Global Land configurations
20 Nov 2013–indefinite | Coordinator: D. Walters | Papers are handled by GMD topical editors | Information

This special issue groups together documentation papers for successive releases of the Met Office Unified Model (UM) Global Atmosphere (GA) and JULES Global Land (GL) configurations. GA and GL are science configurations of the UM and JULES developed for use across weather prediction and climate research timescales. Each paper presents a scientific description of the latest configuration, a fuller description of incremental changes since the previous configuration and a brief summary of their performance.

Nucleus for European Modelling of the Ocean – NEMO
15 Nov 2013–indefinite | Coordinator: P. Oddo | Papers are handled by GMD topical editors | Information

NEMO (Nucleus for European Modelling of the Ocean) is a state-of-the-art modelling framework for oceanographic research, operational oceanography seasonal forecast and climate studies. The NEMO components are NEMO-OPA (the "blue" ocean, modelling the ocean dynamics and solving the primitive equations); NEMO-LIM (the "white ocean" for modelling sea-ice), and NEMO-TOP (the "green ocean" for modelling biogeochemistry). NEMO also includes grid refinement software (AGRIF) and an assimilation component (linear-tangent NEMO-TAM, Observational operators NEMO-OBS, and increment NEMO-ASM). The "blue ocean" component is fundamental to all users. NEMO can also be interfaced to a number of other components such as atmosphere models or alternative other models of sea-ice or biogeochemistry, to enable Earth system modelling.

This Special Issue aims to collect technical and scientific manuscripts dealing with evaluation of model skill and performance as well as development of NEMO components. Submitted manuscripts can cover a wide variety of topics, including process studies, new parameterizations, implementation of new model features and new NEMO configurations. The main scope is to collect relevant and state of the art manuscripts to provide the NEMO users with a single portal to search, discover and understand about the NEMO modelling framework potential and evolution and submit their contributions.

The iLOVECLIM earth system model
01 Jan 2013–indefinite | Coordinator: D. Roche | Papers are handled by GMD topical editors | Information

iLOVECLIM is an intermediate complexity fully coupled climate earth system model that aims at computation and understanding of the climate system on millennial timescale. It is a code fork from the LOVECLIM climate model version 1.2. From its forerunner, iLOVECLIM retains only the physical climate components (atmosphere – ocean – terrestrial vegetation modules). It is developed further to progressively include the components necessary for multi-millenia palaeoclimate and future climate experiments. As such, iLOVECLIM is a tool designed to enhance the integration of model simulations and (palaeo-)data, with an emphasis on the simulation of isotopic tracers throughout all components of the climate system, as indicated by the i prefix. The present, time unlimited, Special Issue hosts the technical documentation of the current version of iLOVECLIM as well as model evaluation manuscripts.

The Norwegian Earth System Model: NorESM; basic development, validation, scientific analyses, and climate scenarios
09 Aug 2012–indefinite | Coordinators: T. Iversen and H. Drange | Papers are handled by GMD topical editors | Information

The Norwegian Earth System Model (NorESM) is a global, coupled model system for the physical climate system, which can be run with various degrees of interactions with bio-geo-chemical processes in the earth system. NorESM is developed as a nationally coordinated effort in Norway, but important parts of the model code are imported from the Community Climate System Model (CCSM) and Community Earth System Model (CESM) projects operated at NCAR on behalf of UCAR in USA.

The NorESM publications in this Special Issue address the first family of NorESM versions which has delivered results to CMIP5. They are based on public releases of CCSM4 (April 1st 2010) and CESM1 (1 July 2010). The full core version includes own developed code for chemistry-aerosol-cloud-radiation interactions in the atmospheric module (CAM4-Oslo); an isopycnic coordinate ocean model developed in Bergen and originating from the Miami Isopycnic Coordinate Ocean Model MICOM); the HAMburg Ocean Carbon Cycle (HAMOCC) model developed at the Max-Plank-Institute for Meteorology, Hamburg and adapted to the isopycnic ocean model framework. Papers developed on the basis of the full core version (NorESM1-ME) or on selected sub-versions (e.g. NorESM1-M, NorESM-L) are welcome in this Special Issue.

Community software to support the delivery of CMIP5
10 Oct 2011–indefinite | Coordinator: S. Easterbrook | Papers are handled by GMD topical editors | Information

CMIP5 represents the most ambitious and computer-intensive model inter-comparison project ever attempted. Integrating a new generation of Earth system models and sharing the model results with a broad community has brought with it many significant technical challenges, along with new community-wide efforts to provide the necessary software infrastructure. This special issue will focus on the software that supports the scientific enterprise for CMIP5, including: couplers and coupling frameworks for Earth system models; the Common Information Model and Controlled Vocabulary for describing models and data; The development of the Earth System Grid Federation; the development of new portals for providing data access to different end-user communities; the scholarly publishing of datasets, and studies of the software development and testing processes used for the CMIP5 models. We especially welcome papers that offer comparative studies of the software approaches taken by different groups, and lessons learnt from community efforts to create shareable software components and frameworks.

Climate model simulations of the last millennium
15 Sep 2011–indefinite | Coordinator: G. A. Schmidt | Papers are handled by GMD topical editors | Information

The climate record of the last millennium holds much promise for identifying the links between forcings and responses at the global, hemispheric and regional scale. The specifications for the Paleoclimate Model Intercomparison Project (PMIP) and the Coupled Model Intercomparison Project (CMIP) simulations include controlled experiments for the period 850 to 1850 CE. The implementation of those experiments, the collation and development of the climate drivers over this period, and the assessment of the model responses are the focus of this special issue of Geoscientific Model Development.

The CSIRO Mk3L climate system model
24 Jun 2011–indefinite | Coordinator: S. Phipps | Papers are handled by GMD topical editors | Information

The CSIRO Mk3L climate system model is a computationally-efficient coupled general circulation model, designed primarily for the study of climate variability and change on millennial timescales. The model distribution is freely available to the research community. This Special Issue allows the history and evolution of Mk3L to be comprehensively documented within a single issue of a journal. Papers are welcome which describe and evaluate components of the model, and which describe and evaluate subsequent enhancements to the modelling system. The issue is also intended for papers which document specific experiments, particularly those which contribute towards Model Intercomparison Projects.

The externalised surface model SURFEX
27 Jan 2011–indefinite | Coordinator: P. Le Moigne | Papers are handled by GMD topical editors

The FAMOUS climate model
28 Jul 2008–indefinite | Coordinator: R. Smith | Papers are handled by GMD topical editors | Information

FAMOUS is climate model based on the widely-used "HadCM3" atmosphere-ocean general circulation code, a version of the UK Met Office Unified Model. Run at a lower resolution than HadCM3 its computational requirements make it suitable for large ensembles and millennial-scale climate simulations. This ongoing Special Issue collects technical documentation and evaluations of the model climatology as FAMOUS is developed and coupled to models of other Earth system components.

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