Modeling ²³⁰Th (and ²³¹Pa) : as an approach to study the intermediate and deep water circulation in the Arctic Ocean ...

• Main Author: Yu, Xiaoxin
• Format: Text
• Language: English
• Published: University of British Columbia 2017
• Subjects: alpha ridge; Arctic; Arctic Ocean; canada basin
• Online Access: https://dx.doi.org/10.14288/1.0343591; https://doi.library.ubc.ca/10.14288/1.0343591

Recently observed ²³⁰Th concentrations in 2007 and 2009 documented very high ²³⁰Th values within the Atlantic layer in the Canada Basin of the Arctic Ocean. Similar levels of high ²³⁰Th had only been previously observed in the Alpha Ridge region, implying that the Alpha Ridge is the potential source of the high ²³⁰Th waters. As the Alpha Ridge is downstream in the classic cyclonic circulation, that circulation is believed to have changed. Motivated by this, a three-dimensional Arctic ²³⁰Th model is configured for the first time to study such change. To simulate the tracer, I coupled a scavenging model, which describes the exchange of ²³⁰Th (and ²³¹Pa) between the dissolved and particulate phases, to an offline NEMO model (the Nucleus for European Modelling of the Ocean) that provides the advection and mixing processes that redistribute the tracers within the ocean. As the scavenging rates of such tracer elements are strongly affected by oceanic particle concentrations, the scavenging rates are parameterized ...