A quantitative study on the terrestrial input to the tropical Northeast Atlantic

Eolian dust and riverine discharge are identified as two key components of terrestrial input to the oceans. They supply micronutrients to the oceans and modify marine carbon biogeochemistry and global climate through dust-land-ocean interactions. However, it is challenging to accurately constrain regional terrestrial inputs in the past, with currently available models and geochemical proxies. The present study utilizes sedimentary wtCaCO₃% records to estimate lithogenic fluxes. The depth-dependance of CaCO₃ preservation in the Holocene and Last Glacial Maximum (LGM) sediments in two major basins of the tropical Northeast Atlantic Ocean is described using a carbonate dissolution model. Results show that during the LGM, reduced dust deposition and slight drops of fluvial input are found in the Canary Basin and Cape Verde margins, respectively. To supplement, carbonate deposition during the LGM indicates that the deep subtropical Northeast Atlantic is seized by more sluggish deep waters relative to today.