Northwest Atlantic 115 Year Coralline Algae Growth Increment Data Halfar, J.; Hetzinger, S.; Adey, W.; Zack, T.; Gamboa, G.; Kunz, B.; Williams, B.; Jacob, D.E. Halfar, J. Hetzinger, S. Adey, W. Zack, T. Gamboa, G. Kunz, B. Williams, B. Jacob, D.E. earth science/paleoclimate/corals and sclerosponges (growth rate,Clathromorphum nereostratum,null,micrometer,null,corals and sclerosponges,null,null,N,growth increment width of coralline red algae species) earth science/paleoclimate/paleoceanography (age,null,null,year Common Era,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleocean (Cape St. Martin>LATITUDE 50.025>LONGITUDE -55.8833) (Ile Longue>LATITUDE 50.2733>LONGITUDE -62.8) (Bay Bulls>LATITUDE 47.3083>LONGITUDE -52.7892) (Quirpon Island>LATITUDE 51.5856>LONGITUDE -55.4248) (Outer Wapitagun Island>LATITUDE 50.195>LONGITUDE -60.0133) Over the past decade coralline algae have increasingly been used as archives of paleoclimate information. Encrusting coralline algae, which deposit annual growth increments in a high Mg-calcite skeleton, are amongst the longest-lived shallow marine organisms. In fact, a live-collected plant has recently been shown to have lived for at least 850 years based on radiometric dating. While a number of investigations have successfully used geochemical information of coralline algal skeletons to reconstruct sea surface temperatures, less attention has been paid to employ growth increment widths as a temperature proxy. Here we explore the relationship between growth and environmental parameters in Clathromorphum compactum collected in the subarctic Northwestern Atlantic. Results indicate that growth-increment widths of individual plants are poorly correlated with instrumental sea surface temperatures (SST). However, an averaged record of multiple growth increment-width time series from a regional network of C. compactum specimens up to 800 km apart reveals strong correlations with annual instrumental SST since 1950. Hence, similar to methods applied in dendrochronology, averaging of multiple sclerochronological records of coralline algae provides accurate climate information. A 115-year growth-increment width master chronology created from modern-collected and museum specimens is highly correlated to multidecadal variability seen in North Atlantic sea surface temperatures. Positive changes in algal growth anomalies record the well-documented regime shift and warming in the northwestern Atlantic during the 1990s. Large positive changes in algal growth anomalies were also present in the 1920s and 1930s, indicating that the impact of a concurrent large-scale regime shift throughout the North Atlantic was more strongly felt in the subarctic Northwestern Atlantic than previously thought, and may have even exceeded the 1990s event with respect to the magnitude of the warming. STUDY NOTES: 115 year growth increment chronology of the massive coralline alga Clathromorphum compactum from the Northwest Atlantic. A network of modern-collected and museum specimens from the shelf regions of Newfoundland and the Gulf of St. Lawrence, Canada, were used to develop a 115-year annual-resolution growth-increment width master chronology. Table 1 Correlation coefficients and significance levels of annually resolved C. compactum growth time series from the Northwest Atlantic, Canada. Note that correlations improve when two transects within the same sample are averaged (e.g. SJ28-L1+2), and when averaging all transects (Master). Correlation coefficients (r) and significance levels (p) from 1950 to end of record with annually averaged ERSSTJul-Sept (Smith et al., 2008); n = number of years used in correlation. AnnualGrowth(um) Sample Site Location Lat. N Long. W Period Average 1SD r p n SJ28-L1 Bay Bulls, St. Johns Newfoundland 47°18.496' 52°47.354' 1933-2007 276 44 0.13 0.333 58 SJ28-L2 Bay Bulls, St. Johns Newfoundland 47°18.496' 52°47.354' 1920-2007 251 39 0.19 0.155 58 SJ21-L2 Bay Bulls, St. Johns Newfoundland 47°18.496' 52°47.354' 1914-2007 335 80 0.26 0.044 58 QP4-4-L1 Quirpon Island Newfoundland 51°35.135' 55°25.490' 1941-2007 303 75 0.34 0.009 58 QP4-4-L2 Quirpon Island Newfoundland 51°35.135' 55°25.490' 1941-2007 335 77 0.28 0.036 58 QP4-3-L1 Quirpon Island Newfoundland 51°35.135' 55°25.490' 1933-2007 326 105 0.2 0.133 58 QP4-3-L2 Quirpon Island Newfoundland 51°35.135' 55°25.490' 1941-2007 358 114 0.2 0.127 58 170176 Cape St. Martin Newfoundland 50°1.5' 55°53' 1871-1963 298 84 0.09 0.761 14 64-27-C Outer Wapitagun Island Gulf St. Lawrence 50°11.7' 60°0.8' 1893-1963 265 73 0.07 0.824 14 64-22-H Ile Longue, Quetachu Bay Gulf St. Lawrence 50°16.4' 62°48' 1872-1963 220 65 0.15 0.606 14 SJ28-L1+2 Bay Bulls, St. Johns Newfoundland 47°18.496' 52°47.354' 1920-2007 264 42 0.23 0.076 58 QP4-4-L1+2 Quirpon Island Newfoundland 51°35.135' 55°25.490' 1941-2007 319 76 0.38 0.003 58 QP4-3-L1+2 Quirpon Island Newfoundland 51°35.135' 55°25.490' 1933-2007 342 110 0.27 0.037 58 Master All Sites 1893-2007 296 43 0.48 0.0001 58 NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Halfar, J. Investigator : Hetzinger, S. Investigator : Adey, W. Investigator : Zack, T. Investigator : Gamboa, G. Investigator : Kunz, B. Investigator : Williams, B. Investigator : Jacob, D.E. 2012-05-23 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/12945 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/halfar2011b/halfar2011b.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/halfar2011b/halfar2011b.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/halfar2011b/halfar2011b.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/halfar2011b/halfar2011b.xls English https://www.ncdc.noaa.gov/paleo/study/12945 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/halfar2011b/halfar2011b.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/halfar2011b/halfar2011b.xls Halfar, J., S. Hetzinger, W. Adey, T. Zack, G. Gamboa, B. Kunz, B. Williams, and D.E. Jacob. 2011. Coralline algal growth-increment widths archive North Atlantic climate variability. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 302, Issues 1-2, March 2011, pp. 71-80. doi:10.1016/j.palaeo.2010.04.009 START YEAR: 1871 AD * END YEAR: 2007 AD -62.8 47.3083 -52.7892 51.5856