# Galapagos Islands and Great Barrier Reef coral and geochemical data from 1729-2010 CE #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # Template Version 4.0 # Encoding: UTF-8 # NOTE: Please cite original publication, NOAA Landing Page URL, dataset and publication DOIs (where available), and date accessed when using downloaded data. # If there is no publication information, please cite investigator, study title, NOAA Landing Page URL, and date accessed. # # Description/Documentation lines begin with '#' followed by a space # Data lines have no '#' # # NOAA_Landing_Page: https://www.ncdc.noaa.gov/access/paleo-search/study/35193 # Landing_Page_Description: NOAA Landing Page of this file's parent study, which includes all study metadata. # # Study_Level_JSON_Metadata: https://www.ncei.noaa.gov/pub/data/metadata/published/paleo/json/noaa-coral-35193.json # Study_Level_JSON_Description: JSON metadata of this data file's parent study, which includes all study metadata. # # Data_Type: Corals and Sclerosponges # # Dataset_DOI: 10.25921/y68n-1x24 # # Science_Keywords: ocean acidification #--------------------------------------- # Resource_Links # # Data_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/coral/east_pacific/thompson2021/gw10-5density-thompson2021.txt # Data_Download_Description: NOAA Template File; Galápagos GW10-5 Monthly Density Data # #--------------------------------------- # Contribution_Date # Date: 2022-01-06 #--------------------------------------- # File_Last_Modified_Date # Date: 2022-04-07 #--------------------------------------- # Title # Study_Name: Galapagos Islands and Great Barrier Reef coral and geochemical data from 1729-2010 CE #--------------------------------------- # Investigators # Investigators: Thompson, Diane M.; McCulloch, Malcolm; Cole, Julia E.; Reed, Emma V.; D'Olivo, Juan P.; Dyez, Kelsey; Lofverstrom, Marcus; Lough, Janice; Cantin, Neal; Tudhope, Alexander W.; Cheung, Anson, H., Vetter, Lael; Edwards, R. Lawrence #--------------------------------------- # Description_Notes_and_Keywords # Description: We leverage geochemical tracers of coral biomineralization–skeletal B/Ca ([CO3-]), d11B (pHcf), and U/Ca ([CO3-])–that constrain the calcifying fluid chemistry, including the aragonite saturation that governs calcification rate (DeCarlo et al., 2018, 2015). We combine these with paleo-environmental tracers that primarily reflect factors external to the coral calcification environment: Sr/Ca (Beck et al., 1992; Corrège et al., 2000), Li/Mg (Hathorne, Felis, et al., 2013; Montagna et al., 2014), and d18O (Weber & Woodhead, 1972; McConnaughey, 1989) (all primarily controlled by SST); Ba/Ca (upwelling, Lea et al., 1989; Shen et al., 1992); and d13C (upwelling, metabolic carbon / photosynthesis, respiration, and reproduction, G. T. Shen et al., 1992). These new recent (1976-2010) and fossil (1729-1733) Galápagos records (Wolf Island, 1o23.15’N, 91o49.90’W) significantly extend the multi-tracer data coverage prior to the industrial era, which allows us to assess the capacity of corals to buffer against changing environmental conditions. We compare our new Galápagos results with published data from the Great Barrier Reef (McCulloch et al., 2017) to contextualize results from the marginal Galápagos reef environment–a comparatively cold, low-saturation, and highly variable environment. # Provided Keywords: boron isotopes, trace elemental geochemistry, ocean acidification, heat stress, ENSO #--------------------------------------- # Publication # Authors: Thompson, Diane M.; McCulloch, Malcolm; Cole, Julia E.; Reed, Emma V.; D'Olivo, Juan P.; Dyez, Kelsey; Lofverstrom, Marcus; Lough, Janice; Cantin, Neal; Tudhope, Alexander W.; Cheung, Anson, H., Vetter, Lael; Edwards, R. Lawrence # Published_Date_or_Year: 2022-02-01 # Published_Title: Marginal reefs under stress: physiological limits render Galápagos corals susceptible to ocean acidification and thermal stress # Journal_Name: AGU Advances # Volume: 3 # Edition: # Issue: 1 # Pages: # Report_Number: e2021AV000509 # DOI: 10.1029/2021AV000509 # Online_Resource: # Full_Citation: # Abstract: Ocean acidification and thermal stress may undermine corals’ ability to calcify and support diverse reef communities, particularly in marginal environments. Coral calcification depends on aragonite supersaturation (Ω>>1) of the calcifying fluid (cf) from which the skeleton precipitates. Corals actively upregulate pHcf relative to seawater to buffer against changes in temperature and dissolved inorganic carbon (DICcf), which together control Ωcf. Here we assess the buffering capacity in modern and fossil corals from the Galápagos Islands that have been exposed to sub-optimal conditions, extreme thermal stress, and ocean acidification. We demonstrate a significant decline in pHcf and Ωcf since the pre-industrial era, trends which are exacerbated during extreme warm years. These results suggest that there are likely physiological limits to corals’ pH buffering capacity, and that these constraints render marginal reefs particularly susceptible to ocean acidification. #--------------------------------------- # Publication # Authors: McCulloch, M.T.; D’Olivo, J. P.; Falter, J.; Holcomb, M.; & Trotter, J. A. # Published_Date_or_Year: 2017 # Published_Title: Coral calcification in a changing world and the interactive dynamics of pH and DIC upregulation.  # Journal_Name: Nature Communications # Volume: 8 # Edition: # Issue: # Pages: # Report_Number: 15686 # DOI: 10.1038/ncomms15686 # Online_Resource: # Full_Citation: # Abstract: Coral calcification is dependent on the mutualistic partnership between endosymbiotic zooxanthellae and the coral host. Here, using newly developed geochemical proxies (d11B and B/Ca), we show that Porites corals from natural reef environments exhibit a close (r2 ~0.9) antithetic relationship between dissolved inorganic carbon (DIC) and pH of the corals’ calcifying fluid (cf). The highest DICcf (~ × 3.2 seawater) is found during summer, consistent with thermal/light enhancement of metabolically (zooxanthellae) derived carbon, while the highest pHcf (~8.5) occurs in winter during periods of low DICcf (~ × 2 seawater). These opposing changes in DICcf and pHcf are shown to maintain oversaturated but stable levels of carbonate saturation (Ocf ~ × 5 seawater), the key parameter controlling coral calcification. These findings are in marked contrast to artificial experiments and show that pHcf upregulation occurs largely independent of changes in seawater carbonate chemistry, and hence ocean acidification, but is highly vulnerable to thermally induced stress from global warming. #--------------------------------------- # Publication # Authors: Reed, E.V.; Thompson, D.M.; Cole, J.E.; Lough, J.M; Cantin, N.E.; Cheung, A.H., Tudhope, A.; Vetter, L., Jimenez, G.; and Edward, R.L. # Published_Date_or_Year: 2021-04-01 # Published_Title: Impacts of coral growth on geochemistry: Lessons from the Galapagos Islands # Journal_Name: Paleoceanography and Paleoclimatology # Volume: 36 # Edition: # Issue: 4 # Pages: # Report_Number: e2020PA004051 # DOI: 10.1029/2020PA004051 # Online_Resource: # Full_Citation: # Abstract: Coral geochemical climate reconstructions can extend our knowledge of global climate variability and trends over timescales longer than those of instrumental data. However, such reconstructions can be biased by coral growth and skeletal architecture, such as growth troughs, off-axis corallite orientation, and changing growth direction. This study quantifies the impact of skeletal architecture and growth on geochemistry using measurements of coral skeletal density, extension rate, and calcification rate, and uses these metrics to improve paleoclimate reconstructions. We present paired geochemistry-density records at Wolf Island, Galápagos, from three Porites lobata corals: two new paired density and geochemistry records from one fossil coral, and new density data from two previously published modern geochemistry records. We categorize each sampling transect used in this record by the quality of its orientation with respect to skeletal architecture. We observe relationships between geochemistry and density that are not detected using extension or calcification rate alone. These density-geochemistry relationships likely reflect both the response of coral growth to environmental conditions and the non-climatic impact of skeletal architecture on geochemistry in sub-optimal sampling transects. Correlations of density with Sr/Ca, Ba/Ca, and Mg/Ca are consistent with the Rayleigh fractionation model of trace element incorporation into coral skeletons. Removing transects with sub-optimal skeletal architecture increases mean reconstructed SST closer to instrumental mean SST, and lowers errors of reconstruction by up to 20%. These results demonstrate the usefulness of coral density data for assessing skeletal architecture and growth when generating coral paleoclimate records. #--------------------------------------- # Publication # Authors: Jimenez, G.; Cole, J.E.; Thompson, D.M.; and Tudhope, A.W. # Published_Date_or_Year: 2018 # Published_Title: Northern Galápagos Corals Reveal Twentieth Century Warming in the Eastern Tropical Pacific # Journal_Name: Geophysical Research Letters # Volume: 45 # Edition: # Issue: # Pages: 1981-1988 # Report_Number: # DOI: 10.1002/2017GL075323 # Online_Resource: # Full_Citation: # Abstract: Models and observations disagree regarding sea surface temperature (SST) trends in the eastern tropical Pacific. We present a new Sr/Ca-SST record that spans 1940–2010 from two Wolf Island corals (northern Gala´pagos). Trend analysis of the Wolf record shows significant warming on multiple timescales, which is also present in several other records and gridded instrumental products. Together, these data sets suggest that most of the eastern tropical Pacific has warmed over the twentieth century. In contrast, recent decades have been characterized by warming during boreal spring and summer (especially north of the equator), and subtropical cooling during boreal fall and winter (especially south of the equator). These SST trends are consistent with the effects of radiative forcing, mitigated by cooling due to wind forcing during boreal winter, as well as intensified upwelling and a strengthened Equatorial Undercurrent. #--------------------------------------- # Publication # Authors: Cheung, A.H.; Cole, J.E.; Thompson, D.M.; Vetter, L., Jimenez, G.; and Tudhope, A.W. # Published_Date_or_Year: 2021-12-01 # Published_Title: Fidelity of the Coral Sr/Ca Paleothermometer Following Heat Stress in the Northern Galápagos # Journal_Name: Paleoceanography and Paleoclimatology # Volume: 36 # Edition: # Issue: 12 # Pages: # Report_Number: e2021PA004323 # DOI: 10.1029/2021PA004323 # Online_Resource: # Full_Citation: # Abstract: Coral Sr/Ca records have been widely used to reconstruct and understand past sea surface temperature (SST) variability in the tropical Pacific. However, in the eastern equatorial Pacific, coral growth conditions are marginal, and strong El Niño events have led to high mortality, limiting opportunities for coral Sr/Ca-based SST reconstructions. In this study, we present two ~25-year Sr/Ca and Mg/Ca records measured on modern Porites lobata from Wolf and Darwin Islands in the northern Galápagos. In these records, we confirm the well-established relationship between Sr/Ca and SST and investigate the impact of heat stress on this relationship. We demonstrate a weakened relationship between Sr/Ca and SST after a major (Degree Heating Months 9°C-months) heat stress event during the 1997–1998 El Niño, with a larger response in the Wolf core. However, removing data that covers the 1997–1998 El Niño from calibration does not improve reconstruction statistics. Nevertheless, we find that excluding data after the 1997–1998 El Niño event from the calibration reduces the SST reconstruction error slightly. These results confirm that coral Sr/Ca is a reliable SST proxy in this region, although it can respond adversely to unusual heat stress. We suggest that noise in Sr/Ca-SST calibrations may be reduced by removing data immediately following large heat extremes. #--------------------------------------- # Funding_Agency # Funding_Agency_Name: NSF # Grant: 1401326/1829613 and 0957881 #--------------------------------------- # Funding_Agency # Funding_Agency_Name: UK Natural Environment Research Council # Grant: NE/H009957/1 #--------------------------------------- # Funding_Agency # Funding_Agency_Name: ARC Centre of Excellence # Grant: CE140100020 #--------------------------------------- # Funding_Agency # Funding_Agency_Name: Boston University # Grant: Startup funds #--------------------------------------- # Site_Information # Site_Name: Wolf Island # Location: Galápagos Islands # Northernmost_Latitude: 1.385833 # Southernmost_Latitude: 1.385833 # Easternmost_Longitude: -91.831667 # Westernmost_Longitude: -91.831667 # Elevation_m: #--------------------------------------- # Data_Collection # Collection_Name: GW10-5Density-Thompson2021 # First_Year: 1729 # Last_Year: 1734 # Time_Unit: year Common Era # Core_Length_m: # Parameter_Keywords: trace metals, oxygen isotopes # Notes: #--------------------------------------- # Chronology_Information # Chronology: Uranium-Thorium # Chronology_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/templates/noaa-wds-paleo-uth-terms.csv # Chronology_Download_Description: Uranium-Thorium terms and definitions. # Chronology_Notes: # 238U_Decay_Constant: # 234U_Decay_Constant: # 230Th_Decay_Constant: # Initial_230Th/232Th: 4.4 ppm +/- 2.2 ppm # Initial_230Th/232Th_Method: Estimated using the values for a material at secular equilibrium, with the bulk earth 232Th/238U value of 3.8. The errors are arbitrarily assumed to be 50%. # Missing_Values: NaN # Chronology_Table: # samp_id depth_mm 238U_ppb 238U_2s_ppb 232Th_ppt 232Th_2s_ppt 230Th_232Th_atom_10e-6 230Th_232Th_atom_2s_10e-6 d234U_meas_permil d234U_meas_2s_permil 230Th_238U_act 230Th_238U_act_2s age_uncorr_BM age_uncorr_2s_yr age_corr_BM age_corr_2s_yr d234U_init_permil d234U_init_2s_permil age_corr_BP1950 age_corr_2s_yr # W-5 NaN 2314.6041590957 2.77942756246694 74.2917436034908 2.31041056540306 1481.88184390906 53.9616301244951 147.164872803928 1.85676691268719 2.88477357145561E-03 5.47562128084923E-05 274.547136536471 5.2364643785168 273.732766998169 5.26785956847738 147.278600182713 1.85820309143345 211.732766998169 5.26785956847738 #--------------------------------------- # Variables # PaST_Thesaurus_Download_Resource: https://www.ncdc.noaa.gov/paleo/skos/past-thesaurus.rdf # PaST_Thesaurus_Download_Description: Paleoenvironmental Standard Terms (PaST) Thesaurus terms, definitions, and relationships in SKOS format. # # Data variables follow that are preceded by "##" in columns one and two. # Variables list, one per line, shortname-tab-var components: what, material, error, units, seasonality, data type, detail, method, C or N for Character or Numeric data) # ## Time_Density age,,,year Common Era,monthly,corals and sclerosponges,interpolated,,N, ## Density_Transect_1 density,Porites lobata,,gram per cubic centimeter,monthly,corals and sclerosponges,interpolated,x-ray densitometry,N,Transect 1; error reported as percent difference of standard from known value; error detail: 1.8 ## Density_Transect_2 density,Porites lobata,,gram per cubic centimeter,monthly,corals and sclerosponges,interpolated,x-ray densitometry,N,Transect 2; error reported as percent difference of standard from known value; error detail: 1.8 ## Average_Density density,Porites lobata,,gram per cubic centimeter,monthly,corals and sclerosponges,averaged,x-ray densitometry,N,average of Transect 1+2; error reported as percent difference of standard from known value; error detail: 1.8 #------------------------ # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: NaN Time_Density Density_Transect_1 Density_Transect_2 Average_Density 1734.208 1.556774 1.394648 1.475711 1734.125 1.550266 1.409836 1.480051 1734.041 1.555086 1.405097 1.480092 1733.958 1.533853 1.421508 1.477681 1733.875 1.546801 1.432703 1.489752 1733.791 1.508389 1.450853 1.479621 1733.708 1.564433 1.444768 1.5046 1733.625 1.493642 1.480161 1.486902 1733.541 1.527947 1.486922 1.507434 1733.458 1.559665 1.498228 1.528946 1733.375 1.545621 1.502931 1.524276 1733.291 1.583695 1.519661 1.551678 1733.208 1.669892 1.548699 1.609296 1733.125 1.654931 1.551328 1.60313 1733.041 1.660586 1.574232 1.617409 1732.958 1.645372 1.630832 1.638102 1732.875 1.660105 1.65969 1.659898 1732.791 1.693599 1.701655 1.697627 1732.708 1.713507 1.755718 1.734613 1732.625 1.702731 1.724747 1.713739 1732.541 1.672439 1.716395 1.694417 1732.458 1.612564 1.721683 1.667124 1732.375 1.661664 1.725626 1.693645 1732.291 1.677236 1.675573 1.676404 1732.208 1.647602 1.630291 1.638946 1732.125 1.72907 1.675987 1.702529 1732.041 1.76563 1.695159 1.730394 1731.958 1.781325 1.701799 1.741562 1731.875 1.775111 1.701333 1.738222 1731.791 1.752958 1.659198 1.706078 1731.708 1.805538 1.623827 1.714683 1731.625 1.761084 1.607484 1.684284 1731.541 1.716807 1.567204 1.642005 1731.458 1.735806 1.542182 1.638994 1731.375 1.733065 1.525408 1.629237 1731.291 1.696481 1.512342 1.604412 1731.208 1.619469 1.519014 1.569241 1731.125 1.414838 1.429551 1.422194 1731.041 1.375388 1.476291 1.42584 1730.958 1.502131 1.455896 1.479014 1730.875 1.597046 1.547038 1.572042 1730.791 1.600873 1.599568 1.600221 1730.708 1.606298 1.633511 1.619905 1730.625 1.630601 1.619213 1.624907 1730.541 1.56395 1.553213 1.558581 1730.458 1.51441 1.476219 1.495314 1730.375 1.525661 1.519132 1.522396 1730.291 1.436456 1.579896 1.508176 1730.208 1.309799 1.524415 1.417107 1730.125 1.301851 1.463338 1.382594 1730.041 1.368047 1.398801 1.383424 1729.958 1.479009 1.359585 1.419297 1729.875 1.493312 1.371831 1.432572 1729.791 1.568951 1.38303 1.475991 1729.708 1.542384 1.469226 1.505805 1729.625 1.507938 1.493321 1.50063 1729.541 1.419403 1.514886 1.467144 1729.458 1.385762 1.47895 1.432356 1729.375 1.383552 1.378874 1.381213 1729.291 1.416938 1.314294 1.365616 1729.208 1.49398 1.301286 1.397633