TEX86 and U_37^k' Applications to Amplify Information on Western Boundary Currents During the Mid- to Late Miocene

Abstract

The Middle Miocene Climatic Optimum (MMCO) is a time period that demonstrated significantly high temperatures, which interrupted the mid-Cenozoic cooling trend. While there is abundant data on deep ocean temperatures during this mid-late Miocene, there is a lack of information on sea surface temperatures (SSTs) in the Northern Pacific Ocean and in other areas of the world. Additionally, climate models based on various CO2 concentrations underestimate mean annual temperature values suggested by proxy records. Thus, more SST data must be gathered to lessen the disparity between proxy data and climate models. Additionally, SSTs can be a useful tool to track the subtropical gyre pattern during the mid- to late Miocene, which plays a pivotal role in the carbon cycle and global heat distribution. An important part of the North Pacific gyre system is the western boundary current, an area where carbon, water, and heat exchanges with the atmosphere are concentrated. Therefore, the proposed research would employ TEX86 and U_37^k' proxies to reconstruct continuous SST records from core sites around the North Pacific western boundary current, specifically the Kuroshio Current, in the mid- to late Miocene to further knowledge of ocean circulation and currents and its effects on past climate.