Amchitka Island Alaska 65 Year Corraline Algae Mg/Ca Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: Please cite original reference when using these data, plus the data file URL and date accessed. NAME OF DATA SET: Amchitka Island Alaska 65 Year Corraline Algae Mg/Ca Data LAST UPDATE: 4/2012 (Original receipt by WDC Paleo) CONTRIBUTORS: Hetzinger, S., J. Halfar, A. Kronz, R.S. Steneck, W. Adey, P.A. Lebednik, and B.R. Schöne IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2012-035 WDC PALEO CONTRIBUTION SERIES CITATION: Hetzinger, S., et al. 2012. Amchitka Island Alaska 65 Year Corraline Algae Mg/Ca Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2012-035. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Hetzinger, S., J. Halfar, A. Kronz, R.S. Steneck, W. Adey, P.A. Lebednik, and B.R. Schöne. 2009. High-Resolution Mg/Ca Ratios in a Coralline Red Alga as a Proxy for Bering Sea Temperature variations from 1902 to 1967. Palaios, June 2009, Vol. 24, no. 6, pp. 406-412. doi: 10.2110/palo.2008.p08-116r http://palaios.geoscienceworld.org/content/24/6/406.abstract ABSTRACT: We present the first continuous, high-resolution record of Mg/Ca variations within an encrusting coralline red alga, Clathromorphum nereostratum, from Amchitka Island, Aleutian Islands. Mg/Ca ratios of individual growth increments were analyzed by measuring a single-point, electron-microprobe transect, yielding a resolution of ~15 samples/year and a 65-year record (1902-1967) of variations. Results show that Mg/Ca ratios in the high-Mg calcite algal framework display pronounced annual cyclicity and archive late spring-late fall sea-surface temperatures (SST) corresponding to the main season of algal growth. Mg/Ca values correlate well to local SST, as well as to an air temperature record from the same region. High spatial correlation to large-scale SST variability in the subarctic North Pacific is observed, with patterns of strongest correlation following the direction of major oceanographic features that play a key role in the exchange of water masses between the North Pacific and the Bering Sea. Our data correlate well with a shorter Mg/Ca record from a second site, corroborating the ability of the alga to reliably record regional environmental signals. In addition, Mg/Ca ratios relate well to a 29-year d18O time series measured on the same sample, providing additional support for the use of Mg in coralline red algae as a paleotemperature proxy that, unlike algal-d18O, is not influenced by salinity fluctuations. Moreover, electron microprobe-based analysis enables higher sampling resolution and faster analysis, thus providing a promising approach for future studies of longer C. nereostratum records and applications to other coralline species. GEOGRAPHIC REGION: North Pacific PERIOD OF RECORD: 1902 - 1967 AD FUNDING SOURCES: DATA FILE URLS: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/hetzinger2009/hetzinger2009.txt ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/hetzinger2009/hetzinger2009.xls DESCRIPTION: 65 year Mg/Ca data from coralline alga collected near Amchitka Island, Aleutian Islands, Alaska. C. nereostratum is a long-lived, shallow-marine crustose coralline algae. Specimen AM-KR-80 8-69-14B collected in August 1969, 25 water depth, coralline algae, species: Clathromorphum nereostratum Sampling location: Kirlof Point, Amchitka Island, Alaska, 51°24.936'N, 179°17.976'E. DATA: Year Mg/Ca (ratio calculated using atom % of Mg and Ca) 1902 0.11937 1903 0.12579 1904 0.12496 1905 0.11982 1906 0.11968 1907 0.10924 1908 0.12843 1909 0.12037 1910 0.12887 1911 0.11449 1912 0.13700 1913 0.11797 1914 0.12821 1915 0.12059 1916 0.12696 1917 0.13283 1918 0.13573 1919 0.12101 1920 0.13987 1921 0.12569 1922 0.12675 1923 0.12365 1924 0.13035 1925 0.13145 1926 0.13788 1927 0.12520 1928 0.12888 1929 0.13815 1930 0.11784 1931 0.13668 1932 0.11993 1933 0.11771 1934 0.13104 1935 0.11983 1936 0.14266 1937 0.13455 1938 0.13949 1939 0.13559 1940 0.12407 1941 0.13457 1942 0.15900 1943 0.13329 1944 0.12856 1945 0.12891 1946 0.13296 1947 0.12835 1948 0.12874 1949 0.13468 1950 0.13997 1951 0.12057 1952 0.12682 1953 0.13399 1954 0.12610 1955 0.13410 1956 0.13652 1957 0.13887 1958 0.13552 1959 0.14190 1960 0.15320 1961 0.13851 1962 0.14268 1963 0.13338 1964 0.14250 1965 0.12433 1966 0.14661 1967 0.12358