Dataset: Dongsha Calcification Rates

Coral core collection and age model. The two coral skeletal cores were collected from living Porites sp. colonies in June 2013 using an underwater pneumatic drill. The north reef flat core (“751”) was  drilled to the base of the colony and reached 1 m in length, whereas the east lagoon core  (“762”) is 0.5 m in length. Both corals lived in approximately 2 m deep water. The cores  were passed through the Siemens Volume Zoom Spiral computed tomography (CT)  scanner at Woods Hole Oceanographic Institution. Skeletal density was determined from the CT scans following the methods of DeCarlo et al. (2014). Annual calcification rates (g cm-2 yr-1 (DeCarlo et al., 2014)) were calculated as the product of annual density (g cm-3 ) and extension (cm yr-1), measured using the automated software program coralCT (DeCarlo & Cohen, 2016).  The age model determined by counting annual growth bands in CT scan images was validated by comparing skeletal δ18 O with satellite sea-surface temperature by matching midpoints of δ18 O and SST. We observe a good correlation when comparing this remote sensing SST product with higher resolution NOAA SST product and with in situ measurement of SST from the northern reef flat.