CaVortEx IV
OCEANOGRAPHIC CRUISE
OBSERVERSHIP
by
Ava Maxam
Department of Life Sciences
University of the West Indies
Introduction
Mesoscale eddies are large, oceanic whirlpools that have been found to traverse the Caribbean from east
to west at a rate of about 4-5 per year. They tend to become stronger as they reach the western Caribbean,
maintaining diameters of hundreds of kilometers with effective depths of over 800 m. One such feature
was the center of investigations during the CaVortEx IV (Caribbean Vorticity Experiment) expedition
undertaken by scientists from the University of Puerto Rico during March 12-25, 2005. The objective was
to investigate eddy effects on biological processes, their contribution to large scale ocean circulation, and
their variability in response to global change.
The eddy known as the Haiti-Jamaica Anti-cyclone (HJA) is a large, mature, anticyclonic feature (see
Figure 1) believed to have originated from complex interactions amongst southern flow through the Mona
Passage, westward Caribbean flow and the Hispaniola coastal projection.
Figure 1: Satellite imagery of sea surface height in the central Caribbean for March 19, 2005. Red
portions depict the Haiti-Jamaica
anticyclonic eddy under investigation during the CaVortEx IV Cruise March 12-26, 2005.
(Processed satellite imagery provided by R. Lopez, UPR, and used with permission.)
Research was conducted on board the RV Pelican (see Photo 2) owned and operated by the Louisiana
University Marine Consortium (LUMCON). The Office of Naval Research (U. S. Navy) serves as the
sponsoring institution for the study of Caribbean eddies with additional support from the NASA-UPR
Tropical Center for Earth and Space Studies (TCESS) and the Department of Marine Sciences (DMS),
UPR (see Photo 1).
In the above photograph (Photo 1) it shows section of Magueyes Island showing facilities at the
Department of Marine Sciences, UPR, where graduate students have access to modern laboratories
equipped with state of the art equipment and Research Vessels for marine and oceanographic research.
In Photo 2 the R/V Pelican docked at Magueyes Island March 11, 2005. The 116
Vessel was designed and outfitted to conduct a variety of oceanographic research missions, including
scientific trawling, large box core sampling, shallow seismic surveys, current meter array and benthic
boundary array deployment and recovery, pla
systems, and underway sampling with towed water sampling systems. The Louisiana Universities Marine
Consortium operates the vessel.
CaVortEx IV Crew
Members on board consisted of twelve scientific crew
Marine Consortium (LUMCON) crew. The scientific team were all from the University of Puerto Rico
Photo1: Magueyes Island.
) it shows section of Magueyes Island showing facilities at the
nt of Marine Sciences, UPR, where graduate students have access to modern laboratories
equipped with state of the art equipment and Research Vessels for marine and oceanographic research.
Photo 2 The R/V Pelican
In Photo 2 the R/V Pelican docked at Magueyes Island March 11, 2005. The 116 – foot long
Vessel was designed and outfitted to conduct a variety of oceanographic research missions, including
scientific trawling, large box core sampling, shallow seismic surveys, current meter array and benthic
boundary array deployment and recovery, plankton sampling, hydrographic casts with CTD
systems, and underway sampling with towed water sampling systems. The Louisiana Universities Marine
Members on board consisted of twelve scientific crew, one observer and six Louisiana Universities
Marine Consortium (LUMCON) crew. The scientific team were all from the University of Puerto Rico
) it shows section of Magueyes Island showing facilities at the
nt of Marine Sciences, UPR, where graduate students have access to modern laboratories
equipped with state of the art equipment and Research Vessels for marine and oceanographic research.
foot long Research
Vessel was designed and outfitted to conduct a variety of oceanographic research missions, including
scientific trawling, large box core sampling, shallow seismic surveys, current meter array and benthic
nkton sampling, hydrographic casts with CTD-rosette
systems, and underway sampling with towed water sampling systems. The Louisiana Universities Marine
, one observer and six Louisiana Universities
Marine Consortium (LUMCON) crew. The scientific team were all from the University of Puerto Rico
and included Drs. José M. López (Principal Investigator), Jorge E. Corredor (Co
(Co - P. I.), Jorge E. Capella, and Fernando Gilbes; and graduate students Alvaro Cabrera, Miguel Canals,
Ramón López, Ana Lozada, Marla Mendez
was invited on board to represent the coastal state of Jamaic
research. As a PhD marine scientist studying physical and biological characteristics of water circulation
around reefs, Ava Maxam of the Life Sciences Dept., UWI, represented the government of Jamaica.
The ship’s crew was provided by LUMCON with Dave Pond as captain, supported by Craig LeBouef
(relief captain), Jim Dorrance (marine technician), Jack Pennington (engineer), José Montoya (marine
technician) and Steve Joltki (chef).
Scientific Methods and Instrumen
Several oceanographic and bio-optical instruments for the measurement of parameters that influence the
photosynthetic behaviour of phytoplankton were employed, including the rosette of instruments in Photo
3 assembled by the Geological and Environme
irradiance and radiance, spectral transmittance and light absorption, variable fluorescence, attenuation and
backscattering.
Photo 3 Bio-optical rosette assembled by scientists from UPR.
The FASTtracka
Fluorometer was another bio
measurements of photosynthetic characteristics of phytoplankton. Also deployed was the Profiling
Reflectance Radiometer (PRR), an optical instrument designed to make profiles of downwelling
irradiance and upwelling radiance through the upper 200 m of t
and included Drs. José M. López (Principal Investigator), Jorge E. Corredor (Co - P. I.), Julio M. Morell
. I.), Jorge E. Capella, and Fernando Gilbes; and graduate students Alvaro Cabrera, Miguel Canals,
Ramón López, Ana Lozada, Marla Mendez-Silvagnoli, Milton Muñoz, and Wilson Rovira. One observer
was invited on board to represent the coastal state of Jamaica and to participate in the oceanographic
research. As a PhD marine scientist studying physical and biological characteristics of water circulation
around reefs, Ava Maxam of the Life Sciences Dept., UWI, represented the government of Jamaica.
s crew was provided by LUMCON with Dave Pond as captain, supported by Craig LeBouef
(relief captain), Jim Dorrance (marine technician), Jack Pennington (engineer), José Montoya (marine
Scientific Methods and Instrumentation
optical instruments for the measurement of parameters that influence the
photosynthetic behaviour of phytoplankton were employed, including the rosette of instruments in Photo
3 assembled by the Geological and Environmental Remote Sensing Laboratory at UPR to measure
irradiance and radiance, spectral transmittance and light absorption, variable fluorescence, attenuation and
optical rosette assembled by scientists from UPR.
Fluorometer was another bio-optical instrument that offered rapid, real-time,
measurements of photosynthetic characteristics of phytoplankton. Also deployed was the Profiling
Reflectance Radiometer (PRR), an optical instrument designed to make profiles of downwelling
irradiance and upwelling radiance through the upper 200 m of the water column, and its sister instrument
P. I.), Julio M. Morell
. I.), Jorge E. Capella, and Fernando Gilbes; and graduate students Alvaro Cabrera, Miguel Canals,
Silvagnoli, Milton Muñoz, and Wilson Rovira. One observer
a and to participate in the oceanographic
research. As a PhD marine scientist studying physical and biological characteristics of water circulation
around reefs, Ava Maxam of the Life Sciences Dept., UWI, represented the government of Jamaica.
s crew was provided by LUMCON with Dave Pond as captain, supported by Craig LeBouef
(relief captain), Jim Dorrance (marine technician), Jack Pennington (engineer), José Montoya (marine
optical instruments for the measurement of parameters that influence the
photosynthetic behaviour of phytoplankton were employed, including the rosette of instruments in Photo
ntal Remote Sensing Laboratory at UPR to measure
irradiance and radiance, spectral transmittance and light absorption, variable fluorescence, attenuation and
time, in situ
measurements of photosynthetic characteristics of phytoplankton. Also deployed was the Profiling
Reflectance Radiometer (PRR), an optical instrument designed to make profiles of downwelling
he water column, and its sister instrument
the PRR 610 for simultaneous reference downwelling irradiance measurements at the sea surface. The
Chelsea N×-Shuttle towed vehicle system measured fluorometry and CTD parameters while undulating
underwater behind a moving vessel at speeds of 5
and 5).
Photo 4 Pelican Marine technicians deploy the N
Photo 5 Deck unit of the N×-Shuttle
underwater.
BIOGEOCHEMICAL
the PRR 610 for simultaneous reference downwelling irradiance measurements at the sea surface. The
Shuttle towed vehicle system measured fluorometry and CTD parameters while undulating
a moving vessel at speeds of 5-15 knots, to operational depths of 150m (see Photos. 4
Marine technicians deploy the N×-Shuttle towed vehicle system.
Shuttle towed vehicle system displaying relayed data as the vehicle ‘flew’
the PRR 610 for simultaneous reference downwelling irradiance measurements at the sea surface. The
Shuttle towed vehicle system measured fluorometry and CTD parameters while undulating
15 knots, to operational depths of 150m (see Photos. 4
Shuttle towed vehicle system.
towed vehicle system displaying relayed data as the vehicle ‘flew’
Water samples were collected using a rosette sampling system (see Photos 6 and 7). Samples were
subjected to a variety of biochemical tests. For dissolved oxyge
carried out on immediately fixed samples. Productivity analysis via radioactive
measurements was carried out in the radioisotope lab. Samples for chlorophyll
analyses were collected directly from Niskin sampling bottles into brown polyethylene sampling bottles.
Nutrients analyses were performed for dissolved organic and inorganic compounds content after filtration
and cold storage of samples.
Photo 6 Pelican Marine technicians deploy the smaller rosette sampler from the J
Water samples were collected using a rosette sampling system (see Photos 6 and 7). Samples were
subjected to a variety of biochemical tests. For dissolved oxygen content an iodometric titration was
carried out on immediately fixed samples. Productivity analysis via radioactive 14
C assimilation
measurements was carried out in the radioisotope lab. Samples for chlorophyll a and primary productivity
llected directly from Niskin sampling bottles into brown polyethylene sampling bottles.
Nutrients analyses were performed for dissolved organic and inorganic compounds content after filtration
Marine technicians deploy the smaller rosette sampler from the J-frame.
Photo 7 The Large A-Frame
Water samples were collected using a rosette sampling system (see Photos 6 and 7). Samples were
n content an iodometric titration was
C assimilation
and primary productivity
llected directly from Niskin sampling bottles into brown polyethylene sampling bottles.
Nutrients analyses were performed for dissolved organic and inorganic compounds content after filtration
frame.
In photograph 7, we see the large A
sampler (on the left) deployed. The van on the right of the photo houses the radioisotope lab.
PHYSICAL
A self-contained broadband 150 kHz RDI ADCP was mounted on a standard R
to provide top-to-bottom velocity profile with each CTD cast, a method known as LADCP profiling. Raw
velocity data were processed to utilize CTD and navigation information. The Sippican Expendable
Bathythermograph (XBT) shown in
of the ocean to depths of up to 1000 meters. XBT’s were deployed over 24
moved between stations.
Photo 8 Larger rosette frame being deployed with the yellow LADCP attached bottom right of frame.
he large A-frame is shown in the background from which the larger rosette
sampler (on the left) deployed. The van on the right of the photo houses the radioisotope lab.
contained broadband 150 kHz RDI ADCP was mounted on a standard Rosette frame (see Photo. 8)
bottom velocity profile with each CTD cast, a method known as LADCP profiling. Raw
velocity data were processed to utilize CTD and navigation information. The Sippican Expendable
Bathythermograph (XBT) shown in Photo. 9 was used to obtain information on the temperature structure
of the ocean to depths of up to 1000 meters. XBT’s were deployed over 24-hour schedules as the ship
Larger rosette frame being deployed with the yellow LADCP attached bottom right of frame.
frame is shown in the background from which the larger rosette
sampler (on the left) deployed. The van on the right of the photo houses the radioisotope lab.
osette frame (see Photo. 8)
bottom velocity profile with each CTD cast, a method known as LADCP profiling. Raw
velocity data were processed to utilize CTD and navigation information. The Sippican Expendable
was used to obtain information on the temperature structure
hour schedules as the ship
Larger rosette frame being deployed with the yellow LADCP attached bottom right of frame.
Photo 9 An XBT is being deployed from the
Stations and Schedule
The CaVortEx IV cruise track comprised of ten sampling stations
Island to Port Antonio and only three on the return leg because of bad weather (see Figure 2). After
leaving Puerto Rican waters bearing west, the cruise first chartered waters of the Dominican Republic,
then Haiti, into Jamaican territory, south towards Columbia, and then north again into Jamaican waters to
dock at Port Antonio for a two-day stopover.
An XBT is being deployed from the Pelican.
The CaVortEx IV cruise track comprised of ten sampling stations – seven on the first leg from Magueyes
Island to Port Antonio and only three on the return leg because of bad weather (see Figure 2). After
leaving Puerto Rican waters bearing west, the cruise first chartered waters of the Dominican Republic,
can territory, south towards Columbia, and then north again into Jamaican waters to
day stopover.
n the first leg from Magueyes
Island to Port Antonio and only three on the return leg because of bad weather (see Figure 2). After
leaving Puerto Rican waters bearing west, the cruise first chartered waters of the Dominican Republic,
can territory, south towards Columbia, and then north again into Jamaican waters to
Figure 2 Map of CaVortEx IV cruise track and sampling stations, March 12
The first station was arrived at after three days of traveling to the general eddy vicinity and then searching
for the center of the circulation. Projection models of sea surface height topography (ssht) were used as a
guide to locate the center. Sampling then
from the centre of the eddy to its periphery. On the return leg a transect from West
but rough seas prevented its completion.
Sampling at each station involved deployment
Water samples were collected or filtered from the Niskins and data downloaded from the instruments.
While in transit between stations the N
released every hour on the hour until arrival at the next stop.
Map of CaVortEx IV cruise track and sampling stations, March 12-25, 2005.
first station was arrived at after three days of traveling to the general eddy vicinity and then searching
for the center of the circulation. Projection models of sea surface height topography (ssht) were used as a
guide to locate the center. Sampling then occurred along a South-North transect (Stations 1
from the centre of the eddy to its periphery. On the return leg a transect from West-East was attempted
but rough seas prevented its completion.
Sampling at each station involved deployment of the Niskin and Optics rosette systems to about 300m.
Water samples were collected or filtered from the Niskins and data downloaded from the instruments.
While in transit between stations the N× – Shuttle System was continuously deployed. Also, XBT’s we
released every hour on the hour until arrival at the next stop.
25, 2005.
first station was arrived at after three days of traveling to the general eddy vicinity and then searching
for the center of the circulation. Projection models of sea surface height topography (ssht) were used as a
North transect (Stations 1-6), extending
East was attempted
of the Niskin and Optics rosette systems to about 300m.
Water samples were collected or filtered from the Niskins and data downloaded from the instruments.
Shuttle System was continuously deployed. Also, XBT’s were
Preliminary Results
In summary, initial results showed that waters were of exceptional optical purity, that is, there was very
little suspended or dissolved material content. The dat
will be made available at a later date to the Department of Life Sciences, UWI, in an official CaVortEx
IV research publication to be completed by the scientists from the UPR.
BIOGEOCHEMICAL DATA
The following graphs in Figure 3 depict salinity, temperature and chlorophyll
of the cruise.
Figure 3 Depth profiles of Salinity, Temperature and Chlorophyll
n summary, initial results showed that waters were of exceptional optical purity, that is, there was very
little suspended or dissolved material content. The data is presented here in preliminary form and the rest
will be made available at a later date to the Department of Life Sciences, UWI, in an official CaVortEx
IV research publication to be completed by the scientists from the UPR.
following graphs in Figure 3 depict salinity, temperature and chlorophyll a along the S to N transect
Depth profiles of Salinity, Temperature and Chlorophyll
n summary, initial results showed that waters were of exceptional optical purity, that is, there was very
a is presented here in preliminary form and the rest
will be made available at a later date to the Department of Life Sciences, UWI, in an official CaVortEx
along the S to N transect
.
In Figure 3, the Depth profiles of Salinity, Temperature and Chlorophyll a along the S-N transect of the
CaVortEx IV cruise. The HJA eddy core is located closest to the south end of the transect. The warmer,
low salinity central core of the eddy was exceptionally deep (see Figure 3 (a) and (b)), depressing
nutrient-rich bottom layers and resulting in low productivity from phytoplankton as evidenced by lowered
chlorophyll a eddy core values in Figure 3 (c).
PHYSICAL DATA
At stations 1 and 2 the eddy structure was clearly defined, with circulation occurring clockwise as
expected with an anti-cyclonic eddy (see Figure 4). LADCP results in Figure 4 showed that current
speeds were strongest just around the centre of the eddy (at Station 1) and at surface. The most active
parts of the eddy seemed to be confined to the top 400m.
CaVortEx IV preliminary LADCP data provided by M. Canals, UPR, and used with permission.
CaVortEx IV preliminary LADCP data provided by M. Canals, UPR, and used with permission.
CaVortEx IV LADCP Vector Field
Figure 4 Graphs of CaVortEx IV LADCP vector fields
Graphs of CaVortEx IV LADCP vector fields
In Figure 4, Graphs of CaVortEx IV LADCP vector fields showing current vectors (m/s) of the
anticyclonic eddy at depth. The uppermost mixed layer depicts the strongest currents near to the center of
the HJA. Circulation is in a clockwise direction.
OPTICAL DATA
Optical data showed that waters of the HJA contained very little suspended or dissolved m
The waters showed very high optical purity.
Observership Experience
During the cruise Ms. Maxam carried out XBT deployments and logs, collected water samples from the
Niskin rosettes and assisted the biogeochemical team in preparing
samples for scintillation analysis in the radioactive laboratory. Her role during the CaVortEx IV mission
allowed her to contribute to the data collection and get exposure to instrumentation and methodology not
available in Jamaica. A small team of graduate students from the University of the West Indies (including
Ms. Maxam) has sought to carry out graduate work in physical oceanography but lack of instrumentation
and local scientific instruction in the field has limited the
participating in this oceanographic cruise is therefore bifold in that the
her personal studies and opens the way for adding a new oceanographic field to the Jamaican curriculum.
The experience to be gained from oceanographic cruises such as the CaVortEx IV is valuable, even more
so if comprehensive pre-cruise collaboration is achieved. For future observer
suggested that their role be more applied and usefu
training beforehand in one unfamiliar component of oceanography with the organizing academic
institution. This can be organized as a student exchange between the University of the West Indies and the
organizing institution.
In Figure 4, Graphs of CaVortEx IV LADCP vector fields showing current vectors (m/s) of the
cyclonic eddy at depth. The uppermost mixed layer depicts the strongest currents near to the center of
the HJA. Circulation is in a clockwise direction.
Optical data showed that waters of the HJA contained very little suspended or dissolved m
The waters showed very high optical purity.
During the cruise Ms. Maxam carried out XBT deployments and logs, collected water samples from the
Niskin rosettes and assisted the biogeochemical team in preparing 14
C-spiked, incubated phytoplankton
samples for scintillation analysis in the radioactive laboratory. Her role during the CaVortEx IV mission
allowed her to contribute to the data collection and get exposure to instrumentation and methodology not
amaica. A small team of graduate students from the University of the West Indies (including
Ms. Maxam) has sought to carry out graduate work in physical oceanography but lack of instrumentation
and local scientific instruction in the field has limited the scope of analysis. The significance of
participating in this oceanographic cruise is therefore bifold in that the knowledge gained contributes to
her personal studies and opens the way for adding a new oceanographic field to the Jamaican curriculum.
xperience to be gained from oceanographic cruises such as the CaVortEx IV is valuable, even more
cruise collaboration is achieved. For future observer-scientists from Jamaica it is
suggested that their role be more applied and useful to both parties by at least a month of academic
training beforehand in one unfamiliar component of oceanography with the organizing academic
institution. This can be organized as a student exchange between the University of the West Indies and the
In Figure 4, Graphs of CaVortEx IV LADCP vector fields showing current vectors (m/s) of the
cyclonic eddy at depth. The uppermost mixed layer depicts the strongest currents near to the center of
Optical data showed that waters of the HJA contained very little suspended or dissolved material content.
During the cruise Ms. Maxam carried out XBT deployments and logs, collected water samples from the
piked, incubated phytoplankton
samples for scintillation analysis in the radioactive laboratory. Her role during the CaVortEx IV mission
allowed her to contribute to the data collection and get exposure to instrumentation and methodology not
amaica. A small team of graduate students from the University of the West Indies (including
Ms. Maxam) has sought to carry out graduate work in physical oceanography but lack of instrumentation
scope of analysis. The significance of
knowledge gained contributes to
her personal studies and opens the way for adding a new oceanographic field to the Jamaican curriculum.
xperience to be gained from oceanographic cruises such as the CaVortEx IV is valuable, even more
scientists from Jamaica it is
l to both parties by at least a month of academic
training beforehand in one unfamiliar component of oceanography with the organizing academic
institution. This can be organized as a student exchange between the University of the West Indies and the
Photo 10 Ms. Maxam (right), scientific observer, in the physical oceanography lab to which she was
assigned. To her right are graduate students Messrs. Canals and Rovira, also assigned to the same area.
Application of Covortex Science to Jamaica
The annual path of the HJA places the eddy in the vicinity of the Pedro Cays, one of Jamaica’s most
productive offshore fishing banks. NLOM Operational Models show that eddies (cyclonic or
anticyclonic) are especially strengthened in this area. Eddies are also responsible for mass
ichthyoplanktonic transport and basin ventilation across the Caribbean. The science utilized by the
CaVortEx expeditions can be applied to our offshore fisheries to document the seasonal effects of these
eddy systems on primary productivity values, current circulation and bio-optical properties of the waters.
Cyclonic eddies are especially important in upwelling nutrient rich bottom waters and increasing
productivity. Anti-cyclonic eddies give the opposite effect of depressing nutrient rich layers and
decreasing productivity.
The implication of the Windward Passage in its contribution to the propagation of these eddies is also
important. This is a busy shipping channel located off the east coast of Jamaica. In the event of
operational discharge, oil spills or other maritime disasters, knowledge of the circulation of the area is
crucial as this can directly affect water quality on the east and southeast coasts.
The remote sensing techniques combined with bio-optical measurements utilized for the CaVortEx
missions are not only useful for wide scale productivity measurements but also for a synoptic overview of
water quality and pollution. This can be very useful in mariculture management, change detection in
habitats (especially after natural disasters), erosion and suspended sediment drift observations,
eutrophication and toxic algal bloom detection.
An obvious advantage is the educational contribution of oceanography components that are not developed
for study in Jamaica. There is much scope for growth of oceanography and pre- and post-cruise
collaboration can allow for didactic exposure of Jamaican students to these fields.
Movies of the 1/16° Global NLOM link, March 2005:
http://www7320.nrlssc.navy.mil/global_nlom/globalnlom/ias.html
Astor, Y., F. Muller-Karger, and M. Scranton (2003), Seasonal and interannual variation in the
hydrography of the Cariaco Basin: Implications for Basin ventilation, Cont. Shelf Res., 23, 125-144.
Blough, N.V., O.C. Zafiriou, and J. Bonilla (1993), Optical absorption spectra of waters from the Orinoco
River outflow: Terrestrial input of colored organic matter to the Caribbean, J. Geophys. Res., 98, 2271-
2278.
For additional information contact:
Ava Maxam,
Department of Life Sciences,
University of the West Indies, Mona,
Kgn 7, Jamaica.
Tel: (876) 927 1202/2753
Fax: (876) 927 1075
Mob: (876) 396 1777
Email: [email protected]