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Pederson started working in the lab asa technician after completing his master’sdegree in forest ecology at Auburn University.He quickly became “hooked on treerings and went on to complete his Ph.D.in Earth and Environmental Science atColumbia in 2005. His primary researchfocuses on the “interaction between climateand ecology, how the climate impacts theenvironment.” He uses trees to reconstructan environment, and his reconstructionshave been used to further our understandingof drought, ecology, and carbon dynamics.Martin-Benito came to Lamont-Dohertyfrom Spain last September to study theforests of Southeast Asia, the dynamicswithin those forests, and their relation tothe environment. Despite their researchfocus on ecology, both Pederson andMartin-Benito were interested in the ship’sremains. Martin-Benito had read aboutthe ship in the newspaper prior to comingto the States. When he arrived at the lab tobegin his work, he was excited to have theopportunity to analyze the ship’s samplesand learn about New York City history inthe process.Finding a ship in Manhattan is rare. Thelast such discovery was made in 1982 nearthe South Street Seaport. Like that ship,the one at the World Trade Center site hadlikely been sunk in the late eighteenth orearly nineteenth century when the city useddebris to expand lower Manhattan into theHudson River. The site was close to whatwas once the location of Lindsey’s Wharfand Lake’s Wharf, and it had been leftundisturbed for at least two hundred years;its location was not included in the originalWorld Trade Center towers’ construction.The sizeable remains of the USS Adrian—named after the excavation site manager—and their condition also made this particularfind exciting. Approximately thirty feetof the wooden hull—estimated to be abouthalf of the original—was intact and relativelywell preserved in its encasement ofsludge.Despite the general enthusiasm, Pedersonand Martin-Benito had their concernsregarding the project. In total, 24 sampleswere taken from the keel, keelson, andplanks of the ship; they were likely to be inan extremely unstable state from havinglain in mud for two centuries. Along withthe condition of the samples, Pederson hadquestions about the original condition ofthe ship itself as debris. “If the city decidedto sink a ship into a landfill, something hadto be seriously wrong with it in the firstplace.” Moreover, the ship’s origins wereentirely unknown. If the Adrian had beenbuilt in a part of the world for which notree-ring chronologies have been derived,the study would come to an abrupt anddisappointing end.Luck, however, was on their side. WhenMartin-Benito began examining thesamples, he discovered that they were inexcellent condition and sturdy enough toallow for drying and sanding, making therings clearer to see and record. One samplewas identified as hickory, which meant thewood was from either eastern Asia or easternNorth America. Logic pointed to NorthAmerica, and since the remaining sampleswere oak—the species for which the labhad the best and most extensive chronologies—theproject quickly became a matterof matching a master chronology.Master chronologies are the lab’s recordsof historic tree-ring data from around thecountry, compiled by director and founderDr. Edward Cook over the last few decades.They are the “perfectly dated yearly seriesof tree-ring width” the lab uses to locatesamples in place and time and to tell thestory of regional forests. Like written andoral accounts in history, the collective groupand the individual tell slightly differentstories. “If you have one piece of woodand you want to compare it to a chronology,you could do that,” Pederson explains.“But if you had three or four from the sameforest, you could date those and make amaster chronology by averaging out theLink back to contents page4 Superscript