Explicit silicate cycling in the Kiel Marine Biogeochemistry Model version 3 (KMBM3) embedded in the UVic ESCM version 2.9

Abstract. We describe and test a new model of biological marine silicate cycling, implemented in the Kiel Marine Biogeochemical Model version 3 (KMBM3), embedded in the University of Victoria Earth System Climate Model (UVic ESCM) version 2.9. This new model adds diatoms, which are a key component of the biological carbon pump, to an existing ecosystem model. This new model combines previously published parameterizations of a diatom functional type, opal production and export with a novel, temperature-dependent dissolution scheme. Modelled steady-state biogeochemical rates, carbon and nutrient distributions are similar to those found in previous model versions. The new model performs well against independent ocean biogeochemical indicators and captures the large-scale features of the marine silica cycle to a degree comparable to similar Earth system models. Furthermore, it is computationally efficient, allowing both fully coupled, long-timescale transient simulations and “offline” transport matrix spinups. We assess the fully coupled model against modern ocean observations, the historical record starting from 1960 and a business-as-usual atmospheric CO2 forcing to the year 2300. The model simulates a global decline in net primary production (NPP) of 1.4 % having occurred since the 1960s, with the strongest declines in the tropics, northern midlatitudes and Southern Ocean. The simulated global decline in NPP reverses after the year 2100 (forced by the extended RCP8.5 CO2 concentration scenario), and NPP returns to 98 % of the pre-industrial rate by 2300. This recovery is dominated by increasing primary production in the Southern Ocean, mostly by calcifying phytoplankton. Large increases in calcifying phytoplankton in the Southern Ocean offset a decline in the low latitudes, producing a global net calcite export in 2300 that varies only slightly from pre-industrial rates. Diatom distribution moves southward in our simulations, following the receding Antarctic ice front, but diatoms are outcompeted by calcifiers across most of their pre-industrial Southern Ocean habitat. Global opal export production thus drops to 75 % of its pre-industrial value by 2300. Model nutrients such as phosphate, silicate and nitrate build up along the Southern Ocean particle export pathway, but dissolved iron (for which ocean sources are held constant) increases in the upper ocean. This different behaviour of iron is attributed to a reduction of low-latitude NPP (and consequently, a reduction in both uptake and export and particle, including calcite scavenging), an increase in seawater temperatures (raising the solubility of particulate iron) and stratification that “traps” the iron near the surface. These results are meant to serve as a baseline for sensitivity assessments to be undertaken with this model in the future.

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Explicit silicate cycling in the Kiel Marine Biogeochemistry Model, version 3 (KMBM3) embedded in the UVic ESCM version 2.9

10.5194/gmd-2020-235 ◽

2020 ◽

Author(s):

Karin Kvale ◽

David P. Keller ◽

Wolfgang Koeve ◽

Katrin J. Meissner ◽

Chris Somes ◽

...

Keyword(s):

Southern Ocean ◽

Primary Production ◽

Large Scale ◽

Climate Model ◽

Net Primary Production ◽

Coupled Model ◽

Co2 Concentration ◽

Ecosystem Model ◽

New Model ◽

Fully Coupled

Abstract. We describe and test a new model of biological marine silicate cycling, implemented in the University of Victoria Earth System Climate Model (UVic ESCM) version 2.9. This new model adds diatoms, which are a key aspect of the biological carbon pump, to an existing ecosystem model. The new model performs well against important ocean biogeochemical indicators and captures the large-scale features of the marine silica cycle. Furthermore it is computationally efficient, allowing both fully-coupled, long-timescale transient simulations, as well as "offline" transport matrix spinups. We assess the fully-coupled model against modern ocean observations, the historical record since 1960, and a business-as-usual atmospheric CO2 forcing to the year 2300. The model simulates a global decline in net primary production (NPP) of 1.3 % having occurred since the 1960s, with the strongest declines in the tropics, northern mid-latitudes, and Southern Ocean. The simulated global decline in NPP reverses after the year 2100 (forced by the extended RCP CO2 concentration scenario), and NPP returns to pre-industrial rates by 2300. This recovery is dominated by increasing primary production in the Southern Ocean, mostly by calcifying phytoplankton. Large increases in calcifying phytoplankton in the Southern Ocean offset a decline in the low latitudes, producing a global net calcite export in 2300 that varies only slightly from pre-industrial rates. Diatoms migrate southward in our simulations, following the receding Antarctic ice front, but are out-competed by calcifiers across most of their pre-industrial Southern Ocean habitat. Global opal export production thus drops to 50 % of its pre-industrial value by 2300. Model nutrients phosphate, silicate, and nitrate build up along the Southern Ocean particle export pathway, but dissolved iron (for which ocean sources are held constant) increases in the upper ocean. This different behaviour of iron is attributed to a reduction of low-latitude NPP (and consequently, a reduction in both uptake and export and particle, including calcite, scavenging), an increase in seawater temperatures (raising the solubility of particle forms), and stratification that "traps" the iron near the surface. These results are meant to serve as a baseline for sensitivity assessments to be undertaken with this model in the future.

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Marine biogeochemical cycling and oceanic CO2 uptake simulated by the NUIST Earth System Model version 3 (NESM v3)

Geoscientific Model Development ◽

10.5194/gmd-13-3119-2020 ◽

2020 ◽

Vol 13 (7) ◽

pp. 3119-3144

Author(s):

Yifei Dai ◽

Long Cao ◽

Bin Wang

Keyword(s):

Primary Production ◽

Carbon Concentration ◽

Large Scale ◽

Net Primary Production ◽

Earth System Model ◽

System Model ◽

Upper Ocean ◽

Co2 Uptake ◽

Earth System ◽

Model Version

Abstract. In this study, we evaluate the performance of the Nanjing University of Information Science and Technology (NUIST) Earth System Model version 3 (hereafter NESM v3) in simulating the marine biogeochemical cycle and carbon dioxide (CO2) uptake. Compared with observations, the NESM v3 reproduces the large-scale patterns of biogeochemical fields reasonably well in the upper ocean, including nutrients, alkalinity, dissolved inorganic, chlorophyll, and net primary production. Some discrepancies between model simulations and observations are identified and the possible causes are investigated. In the upper ocean, the simulated biases in biogeochemical fields are mainly associated with shortcomings in the simulated ocean circulation. Weak upwelling in the Indian Ocean suppresses the nutrient entrainment to the upper ocean, thus reducing biological activities and resulting in an underestimation of net primary production and the chlorophyll concentration. In the Pacific and the Southern Ocean, nutrients are overestimated as a result of strong iron limitation and excessive vertical mixing. Alkalinity is also overestimated in high-latitude oceans due to excessive convective mixing. The major discrepancy in biogeochemical fields is that the model overestimates nutrients, alkalinity, and dissolved inorganic carbon in the deep North Pacific, which is caused by the excessive deep ocean remineralization. The model reasonably reproduces present-day oceanic CO2 uptake. Model-simulated cumulative oceanic CO2 uptake is 149 PgC between 1850 and 2016, which compares well with data-based estimates of 150±20 PgC. In the 1 % yr−1 CO2 increase (1ptCO2) experiment, the diagnosed carbon-climate (γ=-7.9 PgC K−1) and carbon-concentration sensitivity parameters (β=0.88 PgC ppm−1) in the NESM v3 are comparable with those in Coupled Model Intercomparison Project phase 5 (CMIP5) models (β: 0.69 to 0.91 PgC ppm−1; γ: −2.4 to −12.1 PgC K−1). The nonlinear interaction between carbon-concentration and carbon-climate sensitivity in the NESM v3 accounts for 10.3 % of the total carbon uptake, which is within the range of CMIP5 model results (3.6 %–10.6 %). Overall, the NESM v3 can be employed as a useful modeling tool to investigate large-scale interactions between the ocean carbon cycle and climate change.

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Effects of large-scale floating (solar photovoltaic) platforms on hydrodynamics and primary production in a coastal sea from a water column model

Ocean Science ◽

10.5194/os-16-195-2020 ◽

2020 ◽

Vol 16 (1) ◽

pp. 195-208

Author(s):

Thodoris Karpouzoglou ◽

Brigitte Vlaswinkel ◽

Johan van der Molen

Keyword(s):

Primary Production ◽

Water Column ◽

Large Scale ◽

Net Primary Production ◽

Biogeochemical Model ◽

Solar Photovoltaic ◽

Column Model ◽

Coastal Sea ◽

Floating Platforms ◽

The Impact

Abstract. An improved understanding of the effects of floating solar platforms on the ecosystem is necessary to define acceptable and responsible real-world field implementations of this new marine technology. This study examines a number of potential effects of offshore floating solar photovoltaic (PV) platforms on the hydrodynamics and net primary production in a coastal sea for the first time. Three contrasting locations within the North Sea (a shallow and deeper location with well-mixed conditions and a seasonally stratifying location) have been analysed using a water column physical–biogeochemical model: the General Ocean Turbulence Model coupled with the European Regional Seas Ecosystem Model – Biogeochemical Flux Model (GOTM-ERSEM-BFM). The results show strong dependence on the characteristics of the location (e.g. mixing and stratification) and on the density of coverage with floating platforms. The overall response of the system was separated into contributions by platform-induced light deficit, shielding by the platforms of the sea surface from wind and friction induced by the platforms on the currents. For all three locations, light deficit was the dominant effect on the net primary production. For the two well-mixed locations, the other effects of the platforms resulted in partial compensation for the impact of light deficit, while for the stratified location, they enhanced the effects of light deficit. For up to 20 % coverage of the model surface with platforms, the spread in the results between locations was relatively small, and the changes in net primary production were less than 10 %. For higher percentages of coverage, primary production decreased substantially, with an increased spread in response between the sites. The water column model assumes horizontal homogeneity in all forcings and simulated variables, also for coverage with floating platforms, and hence the results are applicable to very-large-scale implementations of offshore floating platforms that are evenly distributed over areas of at least several hundreds of square kilometres, such that phytoplankton remain underneath a farm throughout several tidal cycles. To confirm these results, and to investigate more realistic cases of floating platforms distributed unevenly over much smaller areas with horizontally varying hydrodynamic conditions, in which phytoplankton can be expected to spend only part of the time underneath a farm and effects are likely to be smaller, spatial detail and additional processes need to be included. To do so, further work is required to advance the water column model towards a three-dimensional modelling approach.

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Marine biogeochemical cycling and oceanic CO2 uptake simulated by the NUIST Earth System Model version 3

10.5194/gmd-2019-288 ◽

2019 ◽

Author(s):

Yifei Dai ◽

Long Cao ◽

Bin Wang

Keyword(s):

Primary Production ◽

Large Scale ◽

Net Primary Production ◽

Earth System Model ◽

System Model ◽

Upper Ocean ◽

Carbon Uptake ◽

Co2 Uptake ◽

Earth System ◽

Cmip5 Model

Abstract. In this study, we evaluate the performance of Nanjing University of Information Science and Technology Earth System Model, version 3 (hereafter NESM v3) in simulating the marine biogeochemical cycle and CO2 uptake. Compared with observations, NESM v3 reproduces reasonably well the large-scale patterns of upper ocean biogeochemical fields including nutrients, alkalinity, dissolved inorganic, chlorophyll, and net primary production. The model also reasonably reproduces current-day oceanic CO2 uptake, the total CO2 uptake is 149 PgC from 1850 to 2016. In the 1ptCO2 experiment, the NESM v3 produced carbon-climate (γ=-7.9 PgC/K) and carbon-concentration sensitivity parameters (β=0.8 PgC/ppm) are comparable with CMIP5 model results. The nonlinearity of carbon uptake in the NESM v3 accounts for 10.3% of the total carbon uptake, which is within the range of CMIP5 model results (3.6%~10.6%). Some regional discrepancies between model simulations and observations are identified and the possible causes are investigated. In the upper ocean, the simulated biases in biogeochemical fields are mainly associated with the shortcoming in simulated ocean circulation. Weak upwelling in the Indian Ocean suppresses the nutrient entrainment to the upper ocean, therefore reducing the biological activities and resulting in underestimation of net primary production and chlorophyll concentration. In the Pacific and the Southern Ocean, high-nutrient and low-chlorophyll result from the strong iron limitation. Alkalinity shows high biases in high-latitude oceans due to the strong convective mixing. The major discrepancy in biogeochemical fields is seen in the deep Northern Pacific. The simulated high concentration of nutrients, alkalinity and dissolved inorganic carbon water is too deep due to the excessive deep ocean remineralization. Despite these model-observation discrepancies, it is expected that the NESM v3 can be employed as a useful modeling tool to investigate large scale interactions between the ocean carbon cycle and climate change.

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Climate engineering and the ocean: effects on biogeochemistry and primary production

Biogeosciences ◽

10.5194/bg-14-5675-2017 ◽

2017 ◽

Vol 14 (24) ◽

pp. 5675-5691 ◽

Cited By ~ 12

Author(s):

Siv K. Lauvset ◽

Jerry Tjiputra ◽

Helene Muri

Keyword(s):

Primary Production ◽

Radiative Forcing ◽

Large Scale ◽

Net Primary Production ◽

Stratospheric Aerosol ◽

Climate Impacts ◽

Environmental Drivers ◽

Earth System ◽

Climate Engineering ◽

Induced Changes

Abstract. Here we use an Earth system model with interactive biogeochemistry to project future ocean biogeochemistry impacts from the large-scale deployment of three different radiation management (RM) climate engineering (also known as geoengineering) methods: stratospheric aerosol injection (SAI), marine sky brightening (MSB), and cirrus cloud thinning (CCT). We apply RM such that the change in radiative forcing in the RCP8.5 emission scenario is reduced to the change in radiative forcing in the RCP4.5 scenario. The resulting global mean sea surface temperatures in the RM experiments are comparable to those in RCP4.5, but there are regional differences. The forcing from MSB, for example, is applied over the oceans, so the cooling of the ocean is in some regions stronger for this method of RM than for the others. Changes in ocean net primary production (NPP) are much more variable, but SAI and MSB give a global decrease comparable to RCP4.5 (∼ 6 % in 2100 relative to 1971–2000), while CCT gives a much smaller global decrease of ∼ 3 %. Depending on the RM methods, the spatially inhomogeneous changes in ocean NPP are related to the simulated spatial change in the NPP drivers (incoming radiation, temperature, availability of nutrients, and phytoplankton biomass) but mostly dominated by the circulation changes. In general, the SAI- and MSB-induced changes are largest in the low latitudes, while the CCT-induced changes tend to be the weakest of the three. The results of this work underscore the complexity of climate impacts on NPP and highlight the fact that changes are driven by an integrated effect of multiple environmental drivers, which all change in different ways. These results stress the uncertain changes to ocean productivity in the future and advocate caution at any deliberate attempt at large-scale perturbation of the Earth system.

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A skill assessment of the biogeochemical model REcoM2 coupled to the finite element sea-ice ocean model (FESOM 1.3)

Geoscientific Model Development Discussions ◽

10.5194/gmdd-7-4153-2014 ◽

2014 ◽

Vol 7 (4) ◽

pp. 4153-4249

Author(s):

V. Schourup-Kristensen ◽

D. Sidorenko ◽

D. A. Wolf-Gladrow ◽

C. Völker

Keyword(s):

Finite Element ◽

Southern Ocean ◽

Primary Production ◽

Net Primary Production ◽

Global Scale ◽

Ocean Model ◽

Biogeochemical Model ◽

Biogeochemical Models ◽

The Pacific ◽

The Pacific Ocean

Abstract. In coupled ocean-biogeochemical models, the choice of numerical schemes in the ocean circulation component can have a large influence on the distribution of the biological tracers. Biogeochemical models are traditionally coupled to ocean general circulation models (OGCMs), which are based on dynamical cores employing quasi regular meshes, and therefore utilize limited spatial resolution in a global setting. An alternative approach is to use an unstructured-mesh ocean model, which allows variable mesh resolution. Here, we present initial results of a coupling between the Finite Element Sea-ice Ocean Model (FESOM) and the biogeochemical model REcoM2, with special focus on the Southern Ocean. Surface fields of nutrients, chlorophyll a and net primary production were compared to available data sets with focus on spatial distribution and seasonal cycle. The model produced realistic spatial distributions, especially regarding net primary production and chlorophyll a, whereas the iron concentration became too low in the Pacific Ocean. The modelled net primary production was 32.5 Pg C yr−1 and the export production 6.1 Pg C yr−1. This is lower than satellite-based estimates, mainly due to the excessive iron limitation in the Pacific along with too little coastal production. Overall, the model performed better in the Southern Ocean than on the global scale, though the assessment here is hindered by the lower availability of observations. The modelled net primary production was 3.1 Pg C yr−1 in the Southern Ocean and the export production 1.1 Pg C yr−1. All in all, the combination of a circulation model on an unstructured grid with an ocean biogeochemical model shows similar performance to other models at non-eddy-permitting resolution. It is well suited for studies of the Southern Ocean, but on the global scale deficiencies in the Pacific Ocean would have to be taken into account.

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Water Mass Analysis of Effect of Climate Change on Air–Sea CO2 Fluxes: The Southern Ocean

Journal of Climate ◽

10.1175/jcli-d-11-00291.1 ◽

2012 ◽

Vol 25 (11) ◽

pp. 3894-3908 ◽

Cited By ~ 31

Author(s):

Roland Séférian ◽

Daniele Iudicone ◽

Laurent Bopp ◽

Tilla Roy ◽

Gurvan Madec

Keyword(s):

Climate Change ◽

Carbon Cycle ◽

Southern Ocean ◽

Large Scale ◽

Climate Model ◽

Water Mass ◽

Water Masses ◽

Biogeochemical Model ◽

Carbon Uptake ◽

Intermediate Water

Impacts of climate change on air–sea CO2 exchange are strongly region dependent, particularly in the Southern Ocean. Yet, in the Southern Ocean the role of water masses in the uptake of anthropogenic carbon is still debated. Here, a methodology is applied that tracks the carbon flux of each Southern Ocean water mass in response to climate change. A global marine biogeochemical model was coupled to a climate model, making 140-yr Coupled Model Intercomparison Project phase 5 (CMIP5)-type simulations, where atmospheric CO2 increased by 1% yr−1 to 4 times the preindustrial concentration (4 × CO2). Impacts of atmospheric CO2 (carbon-induced sensitivity) and climate change (climate-induced sensitivity) on the water mass carbon fluxes have been isolated performing two sensitivity simulations. In the first simulation, the atmospheric CO2 influences solely the marine carbon cycle, while in the second simulation, it influences both the marine carbon cycle and earth’s climate. At 4 × CO2, the cumulative carbon uptake by the Southern Ocean reaches 278 PgC, 53% of which is taken up by modal and intermediate water masses. The carbon-induced and climate-induced sensitivities vary significantly between the water masses. The carbon-induced sensitivities enhance the carbon uptake of the water masses, particularly for the denser classes. But, enhancement strongly depends on the water mass structure. The climate-induced sensitivities either strengthen or weaken the carbon uptake and are influenced by local processes through changes in CO2 solubility and stratification, and by large-scale changes in outcrop surface (OS) areas. Changes in OS areas account for 45% of the climate-induced reduction in the Southern Ocean carbon uptake and are a key factor in understanding the future carbon uptake of the Southern Ocean.

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Long term trend of increasing iron stress in Southern Ocean phytoplankton

10.5194/egusphere-egu21-7488 ◽

2021 ◽

Author(s):

Sandy Thomalla ◽

Thomas Ryan-Keogh ◽

Alessandro Tagliabue ◽

Pedro Monteiro

Keyword(s):

Southern Ocean ◽

Primary Production ◽

Net Primary Production ◽

Earth System ◽

Iron Stress ◽

Temporal Scales ◽

Spatial And Temporal Scales ◽

Earth System Models

Net primary production is a major contributor to carbon export in the Southern Ocean and supports rich marine ecosystems [Henley et al., 2020], driven in part by high macronutrient availability and summertime light levels, but ultimately constrained by seasonal changes in light and scarce supply of the essential micronutrient iron [Martin et al., 1990; Boyd, 2002; Tagliabue et al., 2016]. Although changing iron stress is a component of climate-driven trends in model projections of net primary production [Bopp et al., 2013; Laufkotter et al., 2015; Kwiatkowski et al., 2020], our confidence in the accuracy of their predictions is undermined by a lack of in situ constraints at appropriate spatial and temporal scales [Tagliabue et al., 2016; Tagliabue et al., 2020]. Earth System Models tend to predict increased Southern Ocean net primary production by the end of the 21st century, but are characterized by significant inter-model disagreement [Bopp et al., 2013; Kwiatkowski et al., 2020 Biogeosciences].&#160; We show a significant multi-decadal increase in in situ iron stress from 1996 to 2020 that is positively correlated to the Southern Annular Mode and reflected by diminishing in situ net primary production over the last five years. It is not possible to directly infer Fe stress from observed concentrations, which necessitate experimental approaches (in situ open ocean fertilization / bottle nutrient addition experiments or proteomics). These experimental methods cannot be easily applied at appropriate spatial and temporal scales across the Southern Ocean that are required to assess trends in ecosystem status linked to climate drivers. Our novel proxy for in situ iron stress is based on the degree of non-photochemical quenching in relation to available light as a measurable photophysiological response to iron availability [Alderkamp et al., 2019; Schuback & Tortell, 2019; Schallenberg et al., 2020; Ryan-Keogh & Thomalla, 2020]. The proxy was able to reproduce expected variations in iron stress that occur seasonally [Boyd, 2002] and from natural and artificial fertilization [Boyd et al., 2000; Coale et al., 2004; Blain et al., 2008]. A particular strength of this iron stress proxy is that it can be retrospectively applied to data from ships and autonomous platforms with coincident measurements of fluorescence, photosynthetically active radiation and backscatter or beam attenuation to deliver a long-term time series. An iron stress trend of this magnitude in the Southern Ocean, where the primary constraint on net primary production is known to be iron limitation, is likely to have significant implications for the effectiveness of the biological carbon pump globally and may impact the trajectory of climate. The progressive in situ trend of increasing iron stress is however much stronger than net primary production trends from a suite of remote sensing and earth system models, indicating hitherto potential underestimation of ongoing Southern Ocean change.

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The Brazilian Earth System Model version 2.5: Evaluation of its CMIP5 historical simulation

10.5194/gmd-2018-91 ◽

2018 ◽

Author(s):

Sandro F. Veiga ◽

Paulo Nobre ◽

Emanuel Giarolla ◽

Vinicius Capistrano ◽

Manoel Baptista Jr. ◽

...

Keyword(s):

Large Scale ◽

Climate Model ◽

Earth System Model ◽

Meridional Overturning Circulation ◽

System Model ◽

Historical Period ◽

Earth System ◽

Historical Simulation ◽

Model Version ◽

The North

Abstract. The performance of the coupled ocean-atmosphere component of the Brazilian Earth System Model version 2.5 (BESM-OA2.5) simulating the historical period 1850–2005 is evaluated. Following climate model validation procedure, in which the atmospheric and oceanic main variabilities are validated against observation and Reanalysis datasets, the evaluation particularly focuses the mean climate state and the most important large-scale climate variability patterns simulated in the historical run, which is forced by observed greenhouse gas concentration. The most significant upgrades in the model’s components are also presented briefly. BESM-OA2.5 is able to reproduce the most important large-scale variabilities, particularly over the Atlantic (e.g. the North Atlantic Oscillation, the Atlantic Meridional Mode and the Atlantic Meridional Overturning Circulation) and the extratropical modes that occur in both hemispheres. The model's ability in simulating large-scale variabilities indicates its usefulness for seasonal climate prediction and climate change studies.

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Improving climate model coupling through a complete mesh representation: a case study with E3SM (v1) and MOAB (v5.x)

Geoscientific Model Development ◽

10.5194/gmd-13-2355-2020 ◽

2020 ◽

Vol 13 (5) ◽

pp. 2355-2377

Author(s):

Vijay S. Mahadevan ◽

Iulian Grindeanu ◽

Robert Jacob ◽

Jason Sarich

Keyword(s):

Large Scale ◽

Climate Models ◽

Climate Model ◽

Climate Modeling ◽

System Modeling ◽

Spectral Element ◽

Scientific Workflow ◽

Model Coupling ◽

Earth System ◽

Modeling Framework

Abstract. One of the fundamental factors contributing to the spatiotemporal inaccuracy in climate modeling is the mapping of solution field data between different discretizations and numerical grids used in the coupled component models. The typical climate computational workflow involves evaluation and serialization of the remapping weights during the preprocessing step, which is then consumed by the coupled driver infrastructure during simulation to compute field projections. Tools like Earth System Modeling Framework (ESMF) (Hill et al., 2004) and TempestRemap (Ullrich et al., 2013) offer capability to generate conservative remapping weights, while the Model Coupling Toolkit (MCT) (Larson et al., 2001) that is utilized in many production climate models exposes functionality to make use of the operators to solve the coupled problem. However, such multistep processes present several hurdles in terms of the scientific workflow and impede research productivity. In order to overcome these limitations, we present a fully integrated infrastructure based on the Mesh Oriented datABase (MOAB) (Tautges et al., 2004; Mahadevan et al., 2015) library, which allows for a complete description of the numerical grids and solution data used in each submodel. Through a scalable advancing-front intersection algorithm, the supermesh of the source and target grids are computed, which is then used to assemble the high-order, conservative, and monotonicity-preserving remapping weights between discretization specifications. The Fortran-compatible interfaces in MOAB are utilized to directly link the submodels in the Energy Exascale Earth System Model (E3SM) to enable online remapping strategies in order to simplify the coupled workflow process. We demonstrate the superior computational efficiency of the remapping algorithms in comparison with other state-of-the-science tools and present strong scaling results on large-scale machines for computing remapping weights between the spectral element atmosphere and finite volume discretizations on the polygonal ocean grids.

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Explicit silicate cycling in the Kiel Marine Biogeochemistry Model version 3 (KMBM3) embedded in the UVic ESCM version 2.9