An oceanographer comes ashore to study a mysterious Antarctic lake.

Illustrations and Design by HEIDI NOLAND


AS SHE CROSSED the ice, Bess Ward turned to look again at the research camp along the shore. Yellow tents dotted the dark sands of Antarctica, and a glacier's edge loomed behind them.
      She stepped inside a canvas-covered hut and peered down a shaft that ran through the ice to Lake Bonney. A steel cable disappeared into the frigid depths to a bottle that waited 100 feet below.
      The bottle collected water rich with tiny creatures. The bacteria of the lake are holding their breath, and Bess Ward is determined to find out why.

THE BARREN LANDSCAPE of Antarctica's McMurdo valleys contains eight lakes. The lakes are the only ones in the world to maintain a year-round ice cover, and they've been capped for at least 2,000 years. Though ice coats 98 percent of the continent, winds howling off nearby glaciers keep the McMurdo valleys relatively dry.
      This harsh environment looks like a destination fit only for thrill-seeking explorers, but the lakes have attracted the scientific community. The saltwater depths contain microscopic organisms but no other living creatures. For scientists like Ward, the small lakes serve as extremely simple oceans -- nowhere else can scientists find tiny model oceans complete with icy lids. Each lake has its own chemical quirks, but one steals the show.
      "Lake Bonney is a weird cookie," says John Priscu. Priscu is a professor of biology at the University of Montana. He discovered confusing contents in the twin lobes of Lake Bonney during the 1980s. A short and shallow channel connects the two lobes. These Siamese twins of water could hardly be more different. Priscu found astounding levels of dissolved gases in the east lobe, including the world's highest natural concentration of nitrous oxide. His analysis of the west lobe, however, showed more-normal levels of dissolved gases. In such a simple and isolated body of water, the living residents were the logical suspects for causing the lobe's different personalities. Up to one million bacteria lived in each thimble-full of water -- not an unusual amount for saltwater. The bacteria all looked alike under a microscope, leaving Priscu with a contradiction like none he'd seen before: the chemicals of the lobes told a story of opposites, but the bacteria preached unity.
      He decided to seek help from a marine biologist -- one who knew a lot about saltwater bacteria, and one who could work outside a laboratory. He called Bess Ward, a 37-year-old scientist who was already changing the rules of her field. Ward uses the techniques of genetic research to study the DNA of ocean bacteria. While working at Scripps Institution of Oceanography in 1986, Ward began scrutinizing bacteria DNA molecules piece by piece to find genes that could serve as identification tags. Before this technique came to oceanography, marine biologists could identify bacteria only after watching them closely over several days. What the bacteria ate, what they excreted, and how long they lived allowed biologists to guess the bacteria's specific identity. "It's really embarrassing when you think about it," Ward says. "Identification is the most basic question you could ask."
      Her parents raised her to question soft spots in science. Ward was born to two chemists, Charlotte and Curtis Ward, in 1954. Both taught at Auburn University in Alabama, and Bess spent her childhood there with an older sister and two younger brothers. Family members recall Bess asking questions about chemistry research at the dinner table before her young feet could reach the floor.
      While her parents and three siblings stayed in the South, Bess Ward went to Michigan State University and graduated in 1976. The university labeled her degree Zoology, she says, "because my freshman counselor didn't understand what I meant when I said biochemistry."
      To this day, colleagues find it difficult to classify her. In a modern scientific world that encourages a narrow research focus, Ward prefers the big picture. Officially, she is a "biogeochemist," which means she is a biologist, but a biologist who studies geology, and, well, a biologist who also studies chemistry.
      In her graduate career at the University of Washington, this broad view became her trademark. She took lab techniques from immunology, (the study of the body's response to disease), and used them to study ocean bacteria. A graduate student rarely makes a major contribution to science, but her early results now commonly appear in the footnotes of oceanography research papers.
      She wasn't a one-hit wonder of science. After earning her Ph.D. in 1982, she spent the next seven years at Scripps Institution of Oceanography in San Diego. Now 43, Ward heads the marine sciences department at the University of California, Santa Cruz. "I've always loved to work in the field," she says. Ward has collected bacteria from the Arabian Sea, from Antarctic lakes, and from the northern and southern Pacific Ocean. In 1997, she became the youngest scientist -- and the only woman -- to ever receive the Evelyn Hutchinson award, an international prize given to a mid-career scientist who has made exemplary contributions to oceanography and who promises more to come.
      Her success in California hasn't taken Alabama from her personality. She knows how to nurture a conversation. Whether chatting with a colleague, addressing a group of students, or talking over pink solutions of bacterial cultures, she speaks as if she's thinking of a joke. The corners of mouth appear ready to leap into a full smile at any moment.

IN HER OFFICE, she smiles as she sketches a flow chart of chemical compounds. Ward wants to understand how oceans cope with nitrogen. The oceans, the atmosphere, and the land exchange nitrogen gas and chemical compounds built from nitrogen, including ammonium and nitrous oxide. This continuous swapping is called the nitrogen cycle. Ward is trying to uncover the exact role of ocean bacteria in this cycle since they trade nitrogen with ocean water as they excrete and breathe. Bacteria pervade every gallon of every sea, and they have a monumental effect on ocean chemistry.
      Understanding the oceans' nitrogen cycle becomes more crucial every year as scientists recognize that the planet's delicate nitrogen balance is changing rapidly. Humans have doubled the rate at which nitrogen moves between land and sea -- the most severe human effect in all of global chemistry. A 1997 report published by the Ecological Society of America, a professional organization of about 8,000 environmental scientists, outlines a potentially catastrophic combination: ignorance of the global nitrogen cycle mixed with an unparalleled level of human nitrogen tampering. The ESA warns that humans are setting changes in motion without perceiving the consequences.
      The use of nitrogen-based fertilizers accounts for most nitrogen-cycle vandalism, and humans use more every year. World agriculture used more nitrogen fertilizer in the 1980s than in the entire history of agriculture prior to 1980. A great amount of that fertilizer finds its way to the oceans. The ammonia in fertilizers flees readily into the air, and from there, the nitrogen is just one rainy step from the sea.
      "We're basically fertilizing the oceans," Ward says. "And we will see a measurable effect. It may have already started in the deep oceans, but we can only monitor the surface." Scientists know too little about the oceans to predict the impact of ocean fertilization, but Ward says that it might be jarring. Many marine plants and animals depend on nature's supply of nitrogen-based nutrients. In coastal estuary systems, nitrogen poisoning has already caused the population of a few species of algae to explode. The thick swarms of algae appear as brown and red tides which choke fish, plants, and even birds.
      Ward says that certain types of bacteria might be able to process some of the excess nitrogen, in effect softening humanity's careless blow.
      For watching the interplay of nitrogen and bacteria, there is no better venue than the salty confines of Lake Bonney . The capped lake lacks many of the complications that make the study of ocean chemistry difficult -- namely rain, fish, and the mixing of water caused by wind and strong currents. Other scientists are watching Ward's work in Antarctica, hoping it will reveal the private inner workings of the oceans.
      One lobe of Lake Bonney provides an example of chemistry and bacteria in harmony, while the other provides an example of what can go wrong. Nitrous oxide is the most alarming of the east lobe's wealth of nitrogen-based chemicals. A bucket of water from the east lobe contains 5,000 times more nitrous oxide gas than a bucket of ocean water. The lake holds so much nitrous oxide and other gases that the water bubbles when Ward and her colleagues haul it to the surface.
      By analyzing chemicals deposited deep in Antarctic glaciers, scientists have found that the atmosphere contains more nitrous oxide today than it has for the last 45,000 years. Nitrous oxide is a greenhouse gas, meaning it contributes to global warming. Though carbon dioxide is at least 50 times more abundant, nitrous oxide packs more of a warming punch in each molecule.
      Commonly known as laughing gas, nitrous oxide does not just billow from dentists' offices. Industrial sources of nitrous oxide include nylon manufacturing, fossil-fuel burning, and nitrogen fertilizing. When all these sources are added together, they still do not completely account for the abundance of nitrous oxide. Natural factors are also at play, but scientists don't fully understand these factors -- especially the role of oceans and ocean bacteria.
      Lake Bonney is too small to contribute significantly to global increases of nitrous oxide; nevertheless, scientists tie the chemical questions of Lake Bonney to a prognosis for the joint health of the oceans and the atmosphere. In December of 1997, the National Science Foundation decided to fund Ward's continuing work on Lake Bonney with half a million dollars -- 10 times the average NSF research grant.

EVEN THOUGH the study of Lake Bonney promised to be an intriguing experiment, Alabama-bred Ward did not pine for Antarctica. "I never had any intention of being that cold," she says. When asked to join an Antarctic expedition in 1991, Ward agreed to go only after being prodded by her graduate student, Mary Voytek. Voytek had been to Antarctica before, as part of a different research effort. She and Ward joined 1992 and 1994 expeditions to the coldest place on earth.
     The north and south poles receive the same paltry dose of sunshine, but Antarctica is still far colder than its northern cousin. On average, Antarctica is three times higher than any other continent, and since temperature drops with elevation, Antarctica has earned its nickname, "the freezer."
     Ward didn't warm to it. She even met the first hardship before she arrived. A U.S. Navy cargo plane carried scientists from New Zealand to Antarctica's McMurdo Station in an eight-hour flight. "There's no bathroom," Ward says. "They have a bucket, but you're just sitting there with all these Navy guys." In two round trips, Ward has yet to urinate in transit.
     The situation didn't improve much at McMurdo Station, a spartan outpost. It sits next to Robert Falcon Scott's wooden hut, frozen since 1911, when Scott died making his return from the south pole. "McMurdo isn't a very nice place," says Voytek. "It has a disproportionate number of men and an industrial sort of hustle bustle, with the constant noise of machinery." The facility balloons from 150 permanent staff members to more than 1,000 people in the less severe months from November to February. Many of those who arrive for Antarctica's version of summer are scientists. The permanent support staff derisively call the scientists "beakers," in reference to the laboratory flasks used to hold and analyze chemicals. "You get so you like a tent more than you do McMurdo," Ward says.
     Tent life gave her beautiful views and beastly weather. Navy helicopter pilots flew Ward and her scientific colleagues from McMurdo to the shore of Lake Bonney. Photographs from the expeditions show tents and equipment boxes sitting on a lifeless terrain of brown sand. Some of the nearby glaciers wear rust-colored streaks after centuries of gouging metal deposits from the ground, and others glow electric blue. Even in the warmer months, winds dive over these glaciers to destroy experiments and send tents tumbling. Microscopic organisms -- plankton and bacteria -- are the only native life in the area, and they lie deep under the ice.
     "My first trip to Antarctica was horrible," Ward says. A mysterious flu-like illness struck Ward in her first two weeks by the lake. Her worried companions urged her to return to McMurdo Station, but she decided to take her chances in the tent.
     Ward recovered and even tended John Priscu when he suffered a similar illness later that month. "She made me some turkey soup," Priscu says. "Even though she's a vegetarian."
     She also helped run the experiments. The idea of studying Lake Bonney is simple: drill a hole, collect water samples from various depths, and take the bottles home to a comfortable laboratory where no one risks freezing to death. However, the 12 feet of ice, the extreme cold, and the sand-bearing wind complicated each task. After the scientists had created a hole about three feet across, they put together an aluminum and canvas hut around the ice shaft and prepared for their scientific ice-fishing.
     After two months working on the ice, Ward flew back to her Santa Cruz laboratories with dozens of gallons of Lake Bonney. By carefully analyzing the DNA of the lake's bacteria collected in 1992 and 1994, Ward uncovered surprising lake tenants. Many of the bacteria in Lake Bonney were "denitrifiers." Bacteria usually take in oxygen to run their biological engines, but when oxygen is in short supply, denitrifying bacteria can switch fuels. "These bacteria wear denitrification like a necklace," Ward says. "They can put it on or take it off as the situation requires."
     Despite the east lobe's army of denitrifying bacteria, Ward found that it still contained much higher concentrations of nitrogen-based chemicals than the west lobe. When exposed to so much nitrogen, denitrifying bacteria normally treat it as a hungry person would treat a plate of warm biscuits. "They're just not doing their job in the east lobe," Ward says. "Maybe they're pickled." She's only half kidding. Some biologists have suggested that the lake is so cold that the bacteria sit dazed, breathing only sporadically, but the west lobe's bacteria busily process nitrogen in water that is even marginally colder than the east lobe. So why has one neighborhood fallen on hard times? "We really have no idea," Ward says.
     The answer that sits in Lake Bonney may well apply to ocean-sized questions. Ward has identified patches of denitrifying bacteria in the world's seas, and she thinks these bacteria might be able to nullify the harmful effects of nitrogen-fertilizer pollution. However, scientists don't yet understand the series of events that can lead these bacteria to start breathing nitrogen instead of oxygen. Ward hopes to discover a trace mineral or metallic element in the east lobe that has somehow convinced the bacteria that they don't want nitrogen.
     "I'm really excited about the project," she says. "And I want to get back to studying the lake." Her scientific drive opposes her gut reaction to Antarctica itself. Though Ward says she loved her various ocean voyages, Antarctic colleagues say that she did not relish the demanding camping experience. "I don't live or die to go there," Ward says, but she's been there twice and will go again.
     "I'm sure its due to my parents," she says. "I just realize more and more that they're an overwhelming influence for good and bad. A lot of my drive comes from my mother." Ward's parents are southern Baptists, and she says her mother worked to stave off a deep puritanical guilt. High expectations for Charlotte's daughter were a natural extension. If a scientist needs to postpone sleep until the lab electronics are working, so be it, and if the important questions point to the bottom of the planet, that's where she goes.
     In the south pole's warmer season of 1999, Ward and a few colleagues plan to spend another eight weeks testing Lake Bonney. Reinforcing the geology part of her biogeochemist reputation, Ward will search for minerals, trace metals, or anything else that might cause bacteria to lose their appetite for nitrogen. Once again, she will board the cargo plane, visit McMurdo Station with the other "beakers," and take a helicopter ride to Lake Bonney. She will endure the climate, living in a tent for more than a month. She will lean into the wind, cross the ice, and drill for an answer.