Dendrochronological Dating of the World Trade Center Ship, Lower Manhattan, New York City

Abstract

On July 2010, archaeologists monitoring excavation at the World Trade Center site (WTC) in Lower Manhattan found the remains of a portion of a ship's hull. Because the date of construction and origin of the timbers were unknown, samples from different parts of the ship were taken for dendrochronological dating and provenancing. After developing a 280-year long floating chronology from 19 samples of the white oak group (Quercus section Leucobalanus), we used 21 oak chronologies from the eastern United States to evaluate absolute dating and provenance. Our results showed the highest agreement between the WTC ship chronology and two chronologies from Philadelphia (r 5 0.36; t 5 6.4; p , 0.001; n 5 280) and eastern Pennsylvania (r 5 0.35; t 5 6.3; p , 0.001; n 5 280). The last ring dates of the seven best-preserved samples suggest trees for the ship were felled in 1773 CE or soon after. Our analyses suggest that all the oak timbers used to build the ship most likely originated from the same location within the Philadelphia region, which supports the hypothesis independently drawn from idiosyncratic aspects of the vessel's construction, that the ship was the product of a small shipyard. Few late-18 th Century ships have been found and there is little historical documentation of how vessels of this period were constructed. Therefore, the ship's construction date of 1773 is important in confirming that the hull encountered at the World Trade Center represents a rare and valuable piece of American shipbuilding history.

Eleventh-century shift in timber procurement areas for the great houses of Chaco Canyon

“…These techniques are underused in North America, but recent efforts in the northeastern United States have revealed distant, inland sources for 18th-and 19th-century nautical timbers (21,22).…”

Integrating tree-ring and inventory-based measurements of aboveground biomass growth: research opportunities and carbon cycle consequences from a large snow breakage event in the Swiss Alps

“…Projected gradual environmental change and impacts from climate extreme events such as droughts are expected to heavily affect the magnitude of the forest carbon sink in the future (Nemani et al 2003;Beer et al 2010;Reichstein et al 2013;Zscheischler et al 2014). Carbon stocks in regions already prone to drought under current climate conditions will likely decrease, e.g., through increased mortality (Allen et al 2010), while forests at the upper timberline are expected to benefit from the projected climate change, e.g., through prolongation of the growing season (Jolly et al 2005;Manusch et al 2014). Severe droughts can cause more than a 2 standard deviation reduction in carbon uptake, as reported by Bastos et al (2014) for the 2003 and 2010 heat waves in Europe and can even cause some forests being a short-term carbon source (Ciais et al 2005).…”

“…Tree-ring data have been previously used for a variety of research fields ranging from climate reconstructions (Esper et al 2014;Frank et al 2010), forest ecology studies (Esper et al 2007;Svoboda et al 2014), archeological dating (Martin-Benito et al 2014) to reconstructions of geomorphic activity (Gärtner et al 2004;Stoffel and Corona 2014). Tree-rings are a direct measure of radial stem growth, which is closely linked to annual wood formation and carbon accumulation (Bouriaud et al 2005;Kerhoulas and Kane 2012).…”

Assessing site signal preservation in reference chronologies for dendro-provenancing

“…In the literature, t �15 is an uncommon threshold: often, researchers applied more or less rigorously fixed thresholds between t �9 and t �11 [7,8,[40][41][42][43]. Some studies even considered t-values <9 to narrow down the area of provenance [44][45][46][47]. Strictly speaking, the t-value thresholds are not directly comparable between different studies.…”