This is supplementary material to the journal article, Mather, B., Müller, D., Dutkiewicz, A., & Zahirovic, S. Carbon emissions along divergent plate boundaries modulate icehouse-greenhouse climates. Communications Earth and Environment. 2025. It contains: carbon_fluxes_Muller2022_x264_rev2.mp4 - animation showing the carbon outflux from mid-ocean ridges and volcanic arcs (including slab devolatilization and carbonate platform degassing components), carbon influx along subduction zones, and the location of carbonate platforms through the Phanerozoic. Zahirovic_etal_2022_mod-ActiveCarbonatePlatforms.gpml - a GPlates gpml file containing the location and active ages of carbonate platforms from 500 Ma to the present day. plate tectonic stats and carbon fluxes.xlsx - an Excel spreadsheet containing plate tectonic statistics and carbon fluxes presented in the paper. water_fluxes.xlsx - an Excel spreadsheet containing water fluxes used in the melting rates calculation. Muller_etal_2022_SE_1Ga_Opt_PlateMotionModel_v1.1.zip - a zip archive containing the Muller et al 2022 plate motion model and associated rasters. Workflows to constrain the rate of carbonate platform degassing through geological time can be found in the GItHub repository: https://github.com/brmather/carbonate-platform-degassing