Physical control of the distributions of a key Arctic copepod in the northeast Chukchi Sea
Elliott, Stephen M.
MetadataShow full item record
The copepod Calanus glacialis is one of the most important zooplankton taxa in the Arctic shelf seas where it serves as a key grazer, predator, and food source. Its summer distribution and abundance have direct effects on much of the food web, from blooming phytoplankton to migrating bowhead whales. The Chukchi Sea represents a highly advective regime dominated by a barotropicly driven northward flow modulated by wind driven currents that reach the bottom boundary layer of this shallow environment. In addition, a general northward gradient of decreasing temperature and food concentration leads to geographically divergent copepod growth and development rates. The physics of this system establish the connection potential between specific regions. Unless biological factors are uniform and ideal the true connections will be an uneven subset of this physically derived connection potential. In August 2012 and 2013, C. glacialis distributions were observed over Hanna Shoal in the northeast Chukchi Sea. Here we used the Finite Volume Community Ocean Model i-State Configuration Model to advect these distributions forward and back in time to determine the source and sink regions of the transient Hanna Shoal C. glacialis population. We found that Hanna Shoal supplies diapause competent C. glacialis to both the Beaufort Slope and the Chukchi Cap, mainly receives juveniles from the broad slope between Hanna Shoal and Herald Canyon and receives second year adults from as far as the Anadyr Gulf and as close as the broad slope between Hanna Shoal and Herald Canyon. These connection potentials were not sensitive to precise times and locations of release, but were quite sensitive to depth of release. Deeper particles often traveled further than shallow particles due to strong vertical shear in the shallow Chukchi. The 2013 sink region was shifted west relative to the 2012 region and the 2013 adult source region was shifted north relative to the 2012 region.
Submitted in partial fulfillment of the requirements for the degree of Master of Science at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2015
Suggested CitationThesis: Elliott, Stephen M., "Physical control of the distributions of a key Arctic copepod in the northeast Chukchi Sea", 2015-06, DOI:10.1575/1912/7366, https://hdl.handle.net/1912/7366
Showing items related by title, author, creator and subject.
Moffat Varas, Carlos F. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2007-09)Observations of current velocity, temperature, salinity and pressure from a 2-year moored array deployment and four hydrographic cruises conducted by the United States Southern Ocean GLOBEC program on the western Antarctic ...
Frame, Caitlin H. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2011-06)Atmospheric nitrous oxide N2O concentrations have been rising steadily for the past century as a result of human activities. In particular, human perturbation of the nitrogen cycle has increased the N2O production rates ...
Redfield, Alfred C. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1950-07)The tides of coastal embayments derive their energy from the ocean tides rather than from the direct action of lunar and solar gravitational forces. They are considered to be part of co-oscilating systems in which the ...