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In the ocean and on land, many biogeochemical processes have feedbacks on climate. How these processes affect climate or respond to climate changes over long timescales is not always well understood as they are difficult to study in the modern day. The research reported here aims to better understand some of these processes, specifically erosion and sediment deposition, as well as the biogeochemical cycling of barium in the oceans. This research is separated into four projects that use geochemical and computational techniques to link long-term regional climate changes with atmosphere and ocean dynamics. The first two projects use samples from the Arabian Sea, collected during International Ocean Discovery Program Expedition 355 Arabian Sea Monsoon. During this expedition two sites were drilled, Sites U1456 and U1457 located within Laxmi Basin in the Arabian Sea. Samples range in age from 0-11 Ma. In project one, strontium isotope ratios (87Sr/86Sr) from pore fluids from Sites U1456 (n = 21) and U1457 (n = 20) were measured to characterize diagenetic reactions. Pore fluid 87Sr/86Sr is useful to establish fluid-rock reactions, sources, and fluid mixing that may have occurred after deposition, processes that could influence the signal recorded by proxy records from these marine sediment cores. The measured pore fluid 87Sr/86Sr has significant variations at both sites and three distinct zones of diagenetic processes are identified, with similar characteristics at both sites. In the second project, 87Sr/86Sr (n=127) and neodymium isotopes (εNd) (n=38) are measured from the separated clay fraction in sediments from the same cores to investigate their provenance. Provenance is the geographic origin of sediments deposited in a basin and is important to reconstruct so we can understand sediment pathways and constrain paleoclimate and erosion records. The records produced are also compared to 87Sr/86Sr and εNd of the carbonate-free bulk sediment from the same sites in order to investigate the influence of sediment transport on isotopic records. The relationships of 87Sr/86Sr and εNd with grain size suggests the isotopic records are impacted by sediment transport processes. The records reveal changes in provenance, which correlate with monsoon variability at 8-7 Ma, and a link to glacial-interglacial cycles beginning ~3.5 Ma. These new records highlight the potential for proxy records from the clay fraction to not only reveal provenance, but also information on sediment transport processes occurring during deposition. The last two projects use computational techniques to model the marine barium cycle, an element that has been shown to be linked to marine productivity and is applied in many paleoproductivity studies. The third project reviews the processes that affect the formation and preservation of marine barite, as well as those controlling the relationship between the barium and carbon biogeochemical cycles. Additionally, a new approach to modeling the marine barium cycle as a box model is made, with results compared to past modeling efforts. The final project increases the complexity of the modeled marine barium cycle by including it in a global biogeochemical model. The Hamburg Oceanic Carbon Cycle Model Version 2.0 (HAMOCC 2.0) is expanded to include the marine barium (Ba) cycle. The expanded model helps to solidify our understanding of Ba distribution in the ocean and marine sediments, which is then used to test Ba sensitivity to perturbations in the environment.