NOAA and Ships of Opportunity on the US Northeast Continental Shelf
Jack W. Jossi, Robert L. Benway, and Julien R. Goulet
NOAA, National Marine Fisheries Service
Jack Jossi received a BS (biology) from Pacific
University and a BS (physical oceanography) from the University of Washington.
He earned an MS (marine science) from the University of Miami Florida. He has
been with NOAA and its predecessor agencies since 1961 and has designed and
directed various regional and international ocean monitoring programs.
Bob Benway
received his initial training in marine science as a member of the United States
Coast Guard. He earned an AS (Electronics Technology) from the New England Institute
of Technology and has completed course work at the University of Rhode Island
and the Graduate School of Oceanography. Since joining NOAA in 1972 he has been
involved in the development and operation of NMFS's Ships of Opportunity Program
(SOOP) and oversees and coordinates all field operations for SOOP and the MARMAP
Ecosystems Monitoring Surveys.
Julien Goulet
received a BS in earth sciences from Massachusetts Institute of Technology,
and earned an MS in physical oceanography from the University of Rhode Island.
He has been with NOAA and its predecessor agencies since 1965, designing and
implementing database management systems and applying statistical analyses to
fisheries-oceanography problems.
The use of private, merchant, and military vessels on an opportunistic basis
to collect oceanographic and meteorological information has a centuries-long
history. Information was initially gathered by people to help them make a living
from the oceans. It was shared within their communities and passed down through
generations along with other valuable cultural information. As the tools for
using the oceans expanded, so did the geographical range of the information
being gathered. The evolution of maritime commerce and exploration went hand
in hand with an increasing requirement for information about ocean currents,
weather, and the location of marine resources. This information was of great
value and was fiercely guarded against competing interests. The eighteenth century
provided a slight easing of this proprietary policy when Benjamin Franklin,
then Postmaster General, happened to discuss with Nantucket sea captain, Timothy
Folger, the sluggish nature of the delivery of mail from England to New England.
Folger explained that Gulf Stream information, well known to his colleagues
but rejected by the mail packet captains, would reduce these trans-Atlantic
crossings by two weeks. Franklin took advantage of this information to improve
the mail service and began a systematic, cooperative collection of ocean current
and temperature data that continues today. By the middle of the nineteenth century,
the US Navy Hydrographic Office, under the command of Lt. Matthew Fontaine Maury,
had compiled existing information from mariners' log books and inaugurated a
hydrographic reporting program among ships' masters that led to the publication
of the Wind and Current Chart of the North Atlantic. Maury proposed exchanging
this information between maritime nations; his idea was enthusiastically adopted.
In 1925 the British scientist, Alister Hardy,
took his newly designed Continuous Plankton Recorder (CPR) (see Fig. 1)
to the Antarctic on the Discovery expedition. His idea was to apply methods
similar to those employed in meteorology to study the changing plankton distribution,
its causes and effects. In 1932, he began a survey using merchant vessels in
the North Sea to collect plankton at a standard depth of 10m. This survey has
expanded to include the entire North Atlantic. It is the longest and most extensive
marine plankton-monitoring database in existence.
An event in 1937 must be noted for its eventual
role in the use of volunteer observing ships. Athelstan Spilhaus (geophysicist,
inventor, first US ambassador to UNESCO, and Sea Grant visionary) developed
the mechanical bathythermograph used to obtain continuous tracings of temperature
versus depth in the surface layers of the ocean. This instrument was the predecessor
to the expendable bathythermograph which remains a cornerstone in ships of opportunity
sampling today.
With the formation of the National Oceanic and
Atmospheric Administration (NOAA) in 1970, the US and the United Kingdom joined
forces to extend the CPR survey into additional areas of the northwest Atlantic.
Together they worked to develop a new generation of CPR which would continue
the collection of biological data while also sampling the upper layers of the
ocean with sensors for measuring physical and chemical characteristics of the
environment. This partnership, represented in the US by the NOAA-Fisheries Narragansett
Laboratory near the URI Bay Campus, has developed a new suite of ships of opportunity
tools, such as the NuShuttle (see Fig. 2). The formation of NOAA also enhanced
collaboration between the National Weather Service, the National Ocean Service,
the US Maritime Administration, and the National Marine Fisheries Service to
use merchant and other cooperating ocean-going ships for the collection of meteorological,
physical, and biological data along regular routes extending from the United
States coast. The geographical extent of this program, the sophistication of
instrumentation, the kinds of data collected, and the value to the United States
have all grown and should continue to do so. The program is now under the organizational
umbrella of NOAA's Volunteer Ocean Ships (VOS) Program.
The NOAA-Fisheries Narragansett
Laboratory is a major participant in the VOS program, both historically and
scientifically. Monthly monitoring of ocean temperature, salinity, phytoplankton,
and zooplankton has been conducted between Boston and Nova Scotia for nearly
40 years; between New York and Bermuda for more than 28 years; near Georges
Bank for six years (see Fig. 3). The resulting data records are among the longest
of their kind for the US Atlantic coast. These time series play an essential
role in NOAA's responsibility as stewards of the coastal waters of the United
States. They are used to look at broadscale ecological and climatic variations,
natural versus anthropogenic changes, and to develop indices of ocean health
for management purposes to be used much the way economic indices are used. One
important project, now underway, seeks to determine how climatic temperature
change might alter the abundance and composition of lower food chain organisms.
Plankton abundance and temperature in the Middle
Atlantic Bight vary considerably throughout the year and from one year to the
next. We are examining how patterns in the annual and multi-annual temperature
are related to patterns of plankton abundance. Temperature is well known to
affect the growth, migration, reproduction, and metabolic rates of marine organisms
and is also the topic of intense research on global climate change. Any changes
in the timing and magnitude of plankton cycles could have a significant impact
on fish stocks which, at least during their early life stages, depend on sufficient
quantities of certain plankton for their sustenance. For our research, we chose
the early stages of the planktonic copepod, Calanus finmarchicus. This
organism when full grown is slightly smaller than a grain of rice and, like
all plankton, is carried about by ocean currents. We chose it because, in addition
to being an important source of food for young fish, it has a preference for
slightly colder environments. The preference for colder water is useful for
analyzing the effect of changing temperature on planktonic life. Figure
4 shows the average annual variation in temperature and abundance of Calanus
finmarchicus from samples taken between 1978 and 1997. All values come from
a depth of 10m below the surface. The continental shelf (approximately the first
190km from the coast to water depths of about 100m) and the continental slope
(from the edge of the shelf to the Gulf Stream) portions of our transect are
shown in Figure 3a. The temperature on the shelf is generally colder than on
the slope; both reach their annual minimum between March and April and their
maximum in August. Our samples show that young Calanus finmarchicus begin
the annual increase in abundance slightly before the coldest time of the year
and peak four to five months before the hottest. A second pulse in abundance
is seen in both water masses, the more prominent occurring in October in the
shelf water. Figure 5 shows the temperature and abundance
data over the two-decade period and provides a useful perspective for examining
multi-year trends, cycles, and relationships between the two features. Unlike
Figure 4, these features are portrayed as departures above and below the long-term
average (the zero line on the y-axis) in units which have been standardized
to emphasize their importance. Further, because lower temperatures were expected
to relate to higher abundances of Calanus finmarchicus, the scale for
plankton departures on the right of the panels has been inverted. Both features
in both water masses exhibit multi-year cycles of increase and decrease. Except
for a few years in either water mass series, there are no consistent, shared
relationships between trends in water temperature and Calanus abundance.
This is to be expected because relationships in nature are rarely so simple.
However, it does suggest other approaches that may be effective. For example,
Figure 4 shows that on average Calanus finmarchicus abundance begins
a dramatic increase one month (in shelf waters) and at least two months (in
slope waters) before the temperatures begin their spring increase. To successfully
investigate the role of temperature on abundance, one must understand how the
organism increases its biomass when its food is not yet plentiful. Or perhaps
plankton populations are carried to the Middle Atlantic Bight from other regions,
such as the western Gulf of Maine. And finally, our example combines conditions
from the entire continental shelf (nearly 200km wide in this study area) and
ignores annual cycles (see Fig. 4) that differ somewhat between very nearshore,
midshelf, and outer shelf waters. Fortunately, data gathered by ships of opportunity
permit us at the NOAA-Fisheries Narragansett Laboratory to ask and answer these
questions.
Acknowledgments
The authors wish to express their appreciation to the owners, officers,
and crews of the many private, military, government, and academic institutions
who, over the years, have contributed their efforts to make this program possible.