Zooplankton in a Thermohaline Staircase: Do fine-scale temperature and salinity gradients affect the distribution and abundance of zooplankton in the tropical N. Atlantic?
Peter H. Wiebe, Biology
Nancy Copley, Biology
Raymond W. Schmitt, Physical Oceanography
Grant Funded 2010
This Ocean Life Institute (OLI) project will enable the analysis of previously collected samples from a unique stratification regime in the thermocline of the tropical N. Atlantic. The site is within a large area of “thermohaline staircases” where temperature and salinity profiles display a remarkably regular staircase structure, with thin interfaces where temperature and salinity change rapidly alternating with well-mixed layers, 10-30 m thick, with uniform properties. These staircases are a permanent feature of the region, having been observed since the late 1960’s. They are maintained by salt finger convection in the high gradient interfaces and are characterized by enhanced vertical mixing. During a cruise for the Census of Marine Zooplankton (CMarZ) in 2006, a MOCNESS