2023/06/07 by Charine Collins, Joanne O’Callaghan, Malcolm R. Clark +1 · 1 voice
Earth and Planetary Sciences · Environmental Science · #Marine and coastal ecosystems #Marine and fisheries research #Oceanographic and Atmospheric Processes
paper · pdf · doi:10.1080/00288330.2023.2215533
openalex publication_date 2023/06/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/05/22
ABSTRACT The Subtropical Front (STF) and associated biological productivity are topographically locked to the Chatham Rise. Year‐to‐year differences of upper ocean dynamics and associated responses of phytoplankton are valuable for understanding variability in fisheries biomass as well as providing new knowledge of environmental condition for potential seabed mining in this keystone ecosystem. In‐situ observations collected over three consecutive years are used to examine the oceanographic variability on Chatham Rise and its potential causal mechanisms are evaluated from satellite observations and a global atmospheric reanalysis. The water column over Chatham Rise consists of a three‐layer structure comprised of a stable intermediate layer sandwiched between a well‐mixed surface and bottom layer. The in‐situ data showed that different water masses can dominate the surface mixed layer at different times. This variability in surface water masses appears to be related to the position of the STF modulated by wind forcing. Spatial and temporal variability was also observed in the mixed layer depth with the temporal variability driven mainly by wind forcing. A strong relationship was observed between phytoplankton biomass and the depth of the mixed layer with implications for the distribution of biological communities and fisheries at the year‐to‐year timescale on the Chatham Rise.