In mid-June Barney Balch, a scientist at Bigelow Laboratory in West Boothbay In Harbor, saw a nice few days forecast on the heels of a line of thunderstorms and an atmospheric cleansing northwest wind. So he made a round trip reservation for himself and two colleagues on the SCOTIA PRINCE
, the Portland-to-Nova Scotia cruise ferry that carries up to 220 vehicles. They left for Yarmouth, N.S., the evening of June 19, returning the next day.
A well deserved mini-vacation? Not exactly.
Balch had arranged for something most oceanographic research scientists dream of – a spur-of-the-moment trip to gather data on the Gulf of Maine. In good weather. At low cost.
Balch is looking for a special kind of phytoplankton, a single-celled plant called coccolithophore. Its study could teach us about carbon dioxide absorption in the ocean.
If he had to engage a typical research vessel, Balch says, he could have to plan two years in advance to book a five- to ten-day cruise. When packing time and driving time to Woods Hole are included, the event could consume about 20 days of crew and scientists’ time.
The weather on the Gulf of Maine averages one good day out of five. The cost of the research vessel amounts to $50,000 to $100,000 – and two years of planning – for maybe one clear day and one pixel of a satellite image.
Balch needs those clear days to correlate his collected data with satellite imagery.
He figured there had to be a better way. When he learned that in 1972 a scientist from Dalhousie University in Halifax had measured nutrients and zooplankton biomass aboard the SCOTIA PRINCE, he was inspired.
In 1995 Balch came to work at Bigelow Lab full time. After receiving his PhD at Scripps Institution of Oceanography, he worked as a post-doctorate fellow in Nova Scotia and California. He next taught at University of Miami’s Rosenstiel School before moving to Bigelow full-time.
Balch credits Charlie Yentsch for hooking him at age 14 on oceanography. Yentsch, then director of the University of Massachusetts’ research center in Gloucester, went on to found the Bigelow Laboratory for Ocean Sciences in 1974. Balch kept his ties to Yentsch, returning each summer to Bigelow with his wife where they had adjunct positions.
1996, after his move to Maine, Balch began to meet with SCOTIA PRINCE officials. He had to develop a proposal to convince them that he knew what he was doing. With funding from NASA for the project, Balch fabricated a laboratory on a container to take on the Scotia Prince.
In 1998, Balch began to conduct his experiments aboard the SCOTIA PRINCE. He can choose his days now – providing space is available aboard the popular ferry. His success rate with weather is 85-90 percent on the SCOTIA PRINCE, compared to 10-20 percent on the research vessel. With data gathered aboard the ferry he is able to extend the survey from one pixel to 200 to 300 pixels for the 11-hour transit.
Balch tries to fit in 12 trips a season, the equivalent of 120 days on a research vessel. This year he will gather a fifth year of data on the Gulf of Maine.
He’s grateful to the SCOTIA PRINCE owner and crew for their assistance and cooperation. “They are a wonderful company,” Balch says. “None of this would be possible without their terrific attitude.”
On board the SCOTIA PRINCE, Balch looks for evidence of coccolithophores, the phytoplankton whose bloom can turn sea water the color of turquoise. Blooms can cover areas as large as a half a million kilometers and are easily seen by satellites.
While the satellite measures the bloom in space and time, Balch and his colleagues sample the water. The timing of the ferry’s return from Yarmouth allows Balch to sample within a few hours of the satellite’s pass over the Gulf of Maine. The SCOTIA PRINCE crosses over the Jordan Basin, a site of frequent blooms. Blooms often occur around the summer solstice, when the water reaches a certain level of stratification and affects the coccolithophores’ growth.
Balch saw his first coccolithophore bloom in 1988. He moved quickly, calling up some funding agencies and finding time on a research vessel which had free days due to a cancellation. He was able to document that the bloom was coccolithophores.
Balch was applying for grants as fine blooms occurred in 1989 and 1990. His first funding came through in 1991, and Balch found himself with gear, but no blooms that summer to study. Or in 1992, or 1993. Instead, the next several years found blooms in northern waters such as the Bering Sea. Balch participated in a cruise south of Iceland 1991 that studied the biggest bloom ever recorded.
Crossing the Gulf of Maine on the SCOTIA PRINCE beginning in 1998, Balch gathered data but didn’t see a coccolithophore bloom until 2000. He found some in 2001. In the June 20, 2002, crossing, Balch says there wasn’t much coming up in the sampling. But a June 24 satellite indicated a small bloom in the Gulf of Maine.
The portable lab the scientists take aboard the SCOTIA PRINCE is carried in a pickup truck and packed with equipment. Balch has developed sampling equipment to compensate for the ferry’s 18-knot speed.
He uses Bigelow Laboratory’s FlowCAM, which allows a constant flow of seawater through a microscope to be counted and measured while latitude and longitude are assigned to the data. The FlowCAM measures the amount of chlorophyll, water temperature, water salinity and how they mix in the water.
Balch’s five years of study is evolving into a time series studying the health of the Gulf of Maine as a food web on which the health of the sea depends. Already Balch sees major differences.
The deep water of the North Atlantic belches and burps into the bowl of the Gulf of Maine, bringing in new nutrients that drive food production there. Measurements of water temperature and salinity at 100 to 200 meters indicate where the cold water nutrients settle.
Other instruments study how sunlight is absorbed and scattered. The attenuation of light is the sum of its absorption and scattering.
Balch’s interest in light absorption and scattering in the coccolithophores has implications from the minute single-celled plant itself to the health of Earth’s atmosphere and oceans.
Phytoplankton, of which coccolithophores are only one of 5,000 species, are the plants of the ocean. They form the foundation of the complex marine food webs and their number is enormous. The total phytoplankton biomass outweighs the total of all marine animals – zooplankton to whales.
As photosynthesizing organisms, phytoplankton exert a huge influence in the earth’s climate.
The coccolithophore Emiliania huxley interests scientists because it forms calcium carbonate platelets (CaCO3) called coccoliths. When this phytoplankton blooms, it turns sea water a beautiful turquoise.
“You think you have gone aground in Bimini,” says Balch. “It’s a visual marvel.”
Chlorophyll is visible to satellites, but scientists usually can’t identify which kind of phytoplankton produce it. The coccolith plates act as mirrors or sequins. They scatter a significantly greater amounts of light than other phytoplankton so their bloom is specifically identifiable in satellite imagery.
The blooming coccolithophores play a role in the Earth’s complex carbon cycle and man’s 130-year or so effect on it. Right now only half of the anthropogenic (man-made) carbon dioxide (CO2) is found in the atmosphere.
The other half of the man-made CO2 is part of the biological pump that is the earth’s oceans. The fixation of CO2 into plant matter – photoplankton – helps determine how fast this biological pump goes. It influences weather systems around the globe.
The more CO2 is pumped into the ocean, the more acidic the oceans become. Already the amount of manmade CO2 in the ocean is measurable.
Balch also looks at the naturally produced carbon acid from decaying leaf and organic matter that fresh water brings into the Gulf of Maine. So much fresh water enters that it also changes the color of the water. Balch is applying that data to better read satellite imagery.
Dennis Bailey, speaking for the SCOTIA PRINCE, says Balch’s research fits the interests of Prof. Matthew Hudson, owner of the SCOTIA PRINCE. “We’re glad we can save them money,” said Bailey. “We operate in the marine environment and we’re dependent too on a healthy environment.”
It’s a terrific story – Balch and the SCOTIA PRINCE have found a neat way for science and commerce to work together.
For more information, visit www.bigelow.org and www.soes.soton.ac.uk/staff/tt/