Volcanism

How deeply does the climate system connect with the rest of Earth?

• A global survey of midocean ridge spacing shows the influence of Late-Pleistocene sea-level variations on ridge spacing, supporting a link between glacial sea-level variations and mid-ocean ridge magmatic variations 2022. Another approach is to consider crustal thickness and bathymetry data, which also indicates a sea-level influence on variations at the East Pacific Rise 2020.
• A model of how melt production changes at mid-ocean ridges in response to sealevel-induced pressure variations was presented along with evidence from the Australian-Antarctic ridge for significant wavelengths of variability corresponding to the 100 ky, 41 ky, and 23 ky variations in Pleistocene sealevel (2015). Apperance of a sea-level response in ridge bathymetry was criticized in favor of the standard faulting model by Olive et al. (2016), and the discussion is continued in this comment and reply. A good popular overview of how sea level variations may influence ridge processes is here. Much of this work is part of the NSF-funded VOICE project.
• The frequency of ash layer deposits in marine sediments has also been shown to have a significant spectral peak at the obliquity frequency (2012).
• Although generally ascribed to variations in marine carbon pools, changes in atmospheric CO2 concentrations may also involve variations in fluxes from the solid Earth. Glacial unloading appears to have roughly tripled global volcanic activity during the last deglaciation and, quite possibly, also increased the volcanic emission of CO2 (2009).

References

• Huybers, Liautaud, Proistosescu, Boulahanis, Carbotte, Katz, and Langmuir, Influence of late Pleistocene sea-level variations on midocean ridge spacing in faulting simulations and a global analysis of bathymetry, Proceedings of the National Academy of Sciences 119(28), 2022. link.
• Boulahanis, Carbotte, Huybers, Nedimovic, Aghaei, Canales, and Langmuir Do sea level variations influence mid-ocean ridge magma supply? A test using crustal thickness and bathymetry data from the East Pacific Rise , Earth and Planetary Science Letters, 2020. link.
• Crowley, Katz, Huybers, Langmuir, and Park Glacial cycles drive variations in the production of oceanic crust, Science, 2015. pdf
• Huybers and Langmuir, Feedback between deglaciation, volcanism and atmospheric CO2 , Earth and Planetary Science Letters, 2009. pdf and supplementary data
• Huybers, Langmuir, Katz, Ferguson, Priostosescu, and Carbotte Comment on "Sensitivity of seafloor bathymetry to climate-driven fluctuations in mid-ocean ridge magma supply, Science, 2016. pdf
• Kutterolf, Jegen, Mitrovica, Kwasnitschka, Freundt and Huybers A detection of Milankovitch frequencies in global volcanic activity, Geology, 2012. pdf