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Abstract. The numerical model GEOCLIM, a coupled Earth system model for long-term biogeochemical cycle and climate, has been revised. This new version (v 7.0) allows a flexible discretization of the oceanic module, for any paleogeographic configuration, the coupling to any General Circulation Model (GCM), and the determination of all boundary conditions from the GCM coupled to GEOCLIM, notably, the oceanic water exchanges and the routing of land-to-ocean fluxes. These improvements make GEOCLIM7 a unique, powerful tool, devised as an extension of GCMs, to investigate the Earth system evolution at timescales, and with processes that could not be simulated otherwise. We present here a complete description of the model, whose current state gathers features that have been developed and published in several articles since its creation, and some that are original contributions of this article, like the seafloor sediment routing scheme, and the inclusion of orbital parameters. We also present a detailed description of the method to generate the boundary conditions of GEOCLIM, which is the main innovation of the present study. In a second step, we discuss the results of an experiment where GEOCLIM7 is applied to the Turonian paleogeography, with a 10 Myr orbital cycle forcings. This experiment focus on the effects of orbital parameters on oceanic O2 concentration, particularly in the proto-Atlantic and Arctic oceans, where the experiment revealed the largest O2 variations. 

Version 2.0 of GEOCLIM-DynSoil-steady-states with input and configuration files used for the experiments presented in The rise of New Guinea and the fall of Neogene global temperatures; (Martin et al., PNAS, 2023) 

Abstract. The warmer early Pliocene climate featured changes to global sea surface temperature (SST) patterns, namely a reduction in the Equator–pole gradient and the east–west SST gradient in the tropical Pacific, the so-called “permanent El Niño”. Here we investigate the consequences of the SST changes to silicate weathering and thus to atmospheric CO2 on geological timescales. Different SST patterns than today imply regional modifications of the hydrological cycle that directly affect continental silicate weathering in particular over tropical “hotspots” of weathering, such as the Maritime Continent, thus leading to a “weatherability pattern effect”. We explore the impact of Pliocene-like SST changes on weathering using climate model and silicate weathering model simulations, and we deduce CO2 and temperature at carbon cycle equilibrium between solid Earth degassing and silicate weathering. In general, we find large regional increases and decreases in weathering fluxes, and the net effect depends on the extent to which they cancel. Permanent El Niño conditions lead to a small amplification of warming relative to the present day by 0.4 ∘C, suggesting that the demise of the permanent El Niño could have had a small amplifying effect on cooling from the early Pliocene into the Pleistocene. For the reducedEquator–pole gradient, the weathering increases and decreases largely cancel, leading to no detectable difference in global temperature at carbon cycle equilibrium. A robust SST reconstruction of the Pliocene is needed for a quantitative evaluation of the weatherability pattern effect. 

This dataset contains the output files of numerical simulations of the model GEOCLIM-DynSoil-steady-state, that were conducted for the study "The rise of New Guinea and the fall of Neogene global temperatures". Those outputs are modeled fields of erosion rate, silicate weathering flux, regolith thickness and primary phases depletion, on the island of New Guinea, at 30 minutes resolution, and for 19 time slices from 15 Ma to present-day. This dataset also contains additional Python scripts for generating inputs of the model (namely, slope field) and for projecting the 2D New Guinea erosion field on the 1D transect highlighted in the above-mentioned study. files description The 19 files "gdss_output_NG_slope_X.X-X.X.nc" are output files from the model GEOCLIM-DynSoil-steady-state. "X.X-X.X" indicates the time slice targeted by the simulation (e.g., "14.4-13.2" is "14.4 Ma -- 13.2 Ma). Metadata in each file (netCDF format) describes the fields computed by the model and outputted in the files. Instruction to reproduce those outputs are given in the corresponding branch of the model's Github repository (https://doi.org/10.5281/zenodo.8245945) "Total_erosion.csv" is a 3-column table indicating, for each time interval targeted by the modeling study, the beginning and ending of the time interval, and the total eroded material during that interval, as computed by the model MOVE2D, on the New Guinea 1D transect (see "Transect_locations" files) Because the transect is 1D, the "total eroded material" during a time interval is a 2D value, and its units is km^2. "make_slope_inputs.py" is the Python script that generates the slope field for each time interval, accordingly to the erosion rate during that interval. It uses, as input, a modern (0.5-0Ma) slope field, that can be found in the model's Github repository https://doi.org/10.5281/zenodo.8245945. "erosion_projection.py": script to project the erosion field computed by GEOCLIM-DynSoil-steady-state on the 1D transect, and generate the 2 figures (already present in the current repertory): "erosion_transect_map.png": map the New Guinea erosion with the transect location. "transect_erosion.pdf": plot of the erosion rate along the transect. "geoclim.py": Python script storing the erosion function taken from the GEOCLIM model. This function may be used by "erosion_projection.py", as an alternative way to recompute erosion "from scratch". "Transect_location.*": shapefile indicating the location of 1D New Guinea transect (line). 

The modern configuration of the South East Asian Islands (SEAI) evolved over the last fifteen million years, as a result of subduction, arc magmatism, and arc-continent collisions, contributing to both increased land area and high topography.  The presence of the additional land area has been postulated to enhance convective rainfall, facilitating both increased silicate weathering and the development of the modern-day Walker circulation.  Using an Earth System Model in conjunction with a climate-silicate weathering model, we argue instead for a significant role of SEAI topography for both effects.  This dataset archives model output used in this investigation, including simulations using the Community Earth System Model version 1.2, and the climate-silicate weathering model GEOCLIM. All data are in Netcdf format, and were generated either by the Community Earth System Model 1.2 (Hurrell et al. 2013) or the climate-silicate weathering model GEOCLIM (Park et al. 2020).  Model output is organized into 4 tar files: 1) B1850C5.tar Contains model output for the fully coupled CESM1.2 runs, for 2D fields and for 3D pressure vertical velocity (W) between 10S-10N.  Monthly mean data for years 41-110 of the simulations.   Naming convention is No SEAI topography: B1850C5_noSEAItopo_y41-110.nc and B1850C5_noSEAItopo_W_y41-110.nc 50% SEAI topography: B1850C5_0.5SEAItopo_y41-110.nc and B1850C5_0.5SEAItopo_W_y41-110.nc 100% SEAI topography: B1850C5_y41-110.nc and B1850C5_W_y41-110.nc 150% SEAO topogaphy: B1850C5_1.5SEAItopo_y41-110.nc and B1850C5_1.5SEAItopo_W_y41-110.nc 2) E1850C5.tar Contains model output for the slab ocean CESM1.2 runs, for 2D fields and for 3D pressure vertical velocity (W) between 10S-10N.  Monthly mean data for years 21-50 of the simulations.  Naming convention is No SEAI topography: E1850C5_noSEAItopo_y21-50.nc and E1850C5_noSEAItopo_W_y21-50.nc 50% SEAI topography: E1850C5_0.5SEAItopo_y21-50.nc and E1850C5_0.5SEAItopo_W_y21-50.nc 100% SEAI topography: E1850C5_y21-50.nc and E1850C5_W_y21-50.nc 150% SEAO topogaphy:  E1850C5_1.5SEAItopo_y21-50.nc and E1850C5_1.5SEAItopo_W_y21-50.nc 3) GEOCLIM.tar Contains model output from the climate-silicate weathering model GEOCLIM.  Data is provided for all 573 parameter combinations.  All values are climatological annual means. All files contain these variables: GMST: global mean surface temperature (in K) atm_CO2_level: atmospheric pCO2 (in ppm) degassing: globally-integrated CO2 flux (in mol/yr) The files ending with 1xCO2.nc also contain these spatial fields: lithology fraction: fraction of land covered by a lithology class erosion: Regolith erosion rate (m/yr) weathering: Ca-Mg weathering rate (mol/m^2/yr) E1850C5_1xCO2.nc - GEOCLIM output using the Modern SEAI simulation as input, and for CO2 fixed to 286.7ppm.  E1850C5_noSEAI_1xCO2.nc - GEOCLIM output using the no SEAI simulation as input, and for CO2 fixed to 286.7ppm.  E1850C5_noSEAItopo_1xCO2.nc - GEOCLIM output using the flat SEAI simulation as input, and for CO2 fixed to 286.7ppm.  E1850C5_noSEAI_equil.nc - GEOCLIM output using the no SEAI simulation as input, and CO2 adjusted so that system is in carbon flux equilibrium.   E1850C5_noSEAItopo_flatSEAIslope_equil.nc - GEOCLIM output using the flat SEAI simulation as input, and CO2 adjusted so that system is in carbon flux equilibrium.   4) Surface.tar Contains land fraction and surface geopotential fields for the modern SEAI (Landfrac.nc) and no SEAI (Landfrac_noSEAI.nc) simulations References Hurrell, J.W., Holland, M.M., Gent, P.R., Ghan, S., Kay, J.E., Kushner, P.J., Lamarque, J.F., Large, W.G., Lawrence, D., Lindsay, K. and Lipscomb, W.H., 2013. The community earth system model: a framework for collaborative research. Bulletin of the American Meteorological Society, 94(9), pp.1339-1360. Park, Y., Maffre, P., Goddéris, Y., Macdonald, F.A., Anttila, E.S. and Swanson-Hysell, N.L., 2020. Emergence of the Southeast Asian islands as a driver for Neogene cooling. Proceedings of the National Academy of Sciences, 117(41), pp.25319-25326. 

This dataset stores the data of the article The effect of Pliocene regional climate changes on silicate weathering: a potential amplifier of Pliocene-Pleistocene cooling P. Maffre, J. Chiang & N. Swanson-Hysell, Climate of the Past). This study uses a climate model (GCM) to reproduce an estimate of Pliocene Sea Surface Temperature (SST). The main GCM outputs of this modeling (with a slab ocean model) are stored in "GCM_outputs_for_GEOCLIM/", as well as the climatologies from ERA5 reanalysis. The other GCM outputs that were used in intermediary steps (coupled ocean-atmosphere, and fixed SST simulations) are stored in "other_GCM_outputs/". The forcing files (Q-flux) and other boundary conditions to run the "main" GCM simulations can be found in "other_GCM_outputs/Q-flux_derivation/", as well as the scripts used to generate them. Secondly, the mentioned study uses the GCM outputs in "GCM_outputs_for_GEOCLIM/" as inputs for the silicate weathering model GEOCLIM-DynSoil-Steady-State (https://github.com/piermafrost/GEOCLIM-dynsoil-steady-state/tree/PEN), to investigate weathering and equilibrium CO2 changes due to Pliocene SST conditions. The results of these simulations are stored in "GEOCLIM-DynSoil-Steady-State_outputs/". The purpose of this dataset is to provide the raw outputs used to draw the conclusions of Maffre et al. (2023), and to allow the experiments to be reproduced, by providing the scripts to generate the boundary conditions. 

Abstract The geography of the Southeast Asian Islands (SEAI) has changed over the last 15 million years, as a result of tectonic processes contributing to both increased land area and high topography. The presence of the additional land area has been postulated to enhance convective rainfall, facilitating both increased silicate weathering and the development of the modern‐day Walker circulation. Using an Earth System Model in conjunction with a climate‐silicate weathering model, we argue instead for a significant role of SEAItopographyfor both effects. SEAI topography increases orographic rainfall over land, through intercepting moist Asian‐Australian monsoon winds and enhancing land‐sea breezes. Large‐scale atmospheric uplift over the SEAI region increases by ∼14% as a consequence of increased rainfall over the SEAI and enhancement through dynamical ocean‐atmosphere feedback. The atmospheric zonal overturning circulation over the Indo‐Pacific increases modestly arising from dynamical ocean‐atmosphere feedback, more strongly over the tropical Indian Ocean. On the other hand, the effect of the SEAI topography on global silicate weathering is substantial, resulting in a ∼109 ppm reduction in equilibriumpCO₂and decrease in global mean temperature by ∼1.7ºC. The chemical weathering increase comes from both enhanced physical erosion rates and increased rainfall due to the presence of SEAI topography. The lowering ofpCO₂by SEAI topography also enhances the Indo‐Pacific atmospheric zonal overturning circulation. Our results support a significant role for the progressive emergence of SEAI topography in global cooling over the last several million years. 

Steep topography, a tropical climate, and mafic lithologies contribute to efficient chemical weathering and carbon sequestration in the Southeast Asian islands. Ongoing arc–continent collision between the Sunda-Banda arc system and Australia has increased the area of subaerially exposed land in the region since the mid-Miocene. Concurrently, Earth’s climate has cooled since the Miocene Climatic Optimum, leading to growth of the Antarctic ice sheet and the onset of Northern Hemisphere glaciation. We seek to evaluate the hypothesis that the emergence of the Southeast Asian islands played a significant role in driving this cooling trend through increasing global weatherability. To do so, we have compiled paleoshoreline data and incorporated them into GEOCLIM, which couples a global climate model to a silicate weathering model with spatially resolved lithology. We find that without the increase in area of the Southeast Asian islands over the Neogene, atmosphericpCO₂would have been significantly higher than preindustrial values, remaining above the levels necessary for initiating Northern Hemisphere ice sheets.