# Equatorial Pacific 1.1 Million Year Nitrogen Isotope Data #----------------------------------------------------------------------- # 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 these downloaded data. If there is no publication information, please cite investigator, study title, NOAA Landing Page URL, and date accessed. # # NOAA_Landing_Page: https://www.ncei.noaa.gov/access/paleo-search/study/13607 # 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-ocean-13607.json # Study_Level_JSON_Description: JSON metadata of this file's parent study, which includes all study metadata. # # Data_Type: Paleoceanography # # Dataset_DOI: 10.25921/kdeh-1309 # # Science_Keywords: #-------------------- # Resource_Links # # Data_Download_Resource: https://www.ncei.noaa.gov/pub/data/paleo/contributions_by_author/rafter2012/rafter2012rndb74p.txt # Data_Download_Description: NOAA Template File; Nitrogen Isotope Data # # Original_Source_URL: # Original_Source_Description: # #-------------------- # Contribution_Date # Date: 2012-12-11 #-------------------- # File_Last_Modified_Date # Date: 2022-10-07 #-------------------- # Title # Study_Name: Equatorial Pacific 1.1 Million Year Nitrogen Isotope Data #-------------------- # Investigators # Investigators: Rafter, P.A.(https://orcid.org/0000-0002-6352-7593); Charles, C.D.(https://orcid.org/0000-0003-4016-2365) #-------------------- # Description_Notes_and_Keywords # Description: Nitrogen isotope (d15N) data from Equatorial Pacific sediment cores for the past 1.1 million years #-------------------- # Publication # Authors: Rafter, P.A. and C.D. Charles # Journal_Name: Paleoceanography # Published_Title: Pleistocene equatorial Pacific dynamics inferred from the zonal asymmetry in sedimentary nitrogen isotopes # Published_Date_or_Year: 2012 # Volume: 27 # Pages: # Issue: # Report_Number: PA3102 # DOI: 10.1029/2012PA002367 # Full_Citation: # Abstract: There is little agreement among models in predicting the average state of the tropical Pacific when subjected to enhanced greenhouse gas forcing. This uncertainty emphasizes the importance of reconstructing past variability in tropical Pacific climate through episodes of significant and estimable radiative forcing. Thus far, efforts along these lines have concentrated primarily on inferences of sea surface temperature variability from deep-sea sediments. Here we offer a different view of the equatorial Pacific over the past ~1.2 million years (Myr) - before and after the mid-Pleistocene shift in the structure of ice ages. The zonal gradient in the nitrogen isotopic composition of sediment across the equatorial Pacific reflects nutrient delivery to the surface and, by extension, ocean dynamical properties. Over the last ~1.2 Myr, the variability of eastern equatorial Pacific nutrient upwelling (inferred from relative nitrate utilization) was highly correlated with local seasonal insolation. By contrast, nitrate utilization was insensitive to the 100,000 year cycle that dominated many other aspects of the Pleistocene ice ages, including greenhouse gas concentrations. A strong linear relationship between relative nitrate utilization and seasonal insolation over the past ~1 million years suggests a predictable response of one primary determinant of tropical Pacific climate change. #-------------------- # Funding_Agency # Funding_Agency_Name: Ocean Drilling Program # Grant_Number: Schlanger Fellowship #-------------------- # Funding_Agency # Funding_Agency_Name: Whole Earth Society # Grant_Number: #-------------------- # Site_Information # Site_Name: RNDB-74P # Location: Western Pacific Ocean # Northernmost_Latitude: .319 # Southernmost_Latitude: .319 # Easternmost_Longitude: 159.361 # Westernmost_Longitude: 159.361 # Elevation: -2520 #-------------------- # Data_Collection # Collection_Name: Rafter2012RNDB74P # First_Year: 155000 # Last_Year: 8000 # Time_Unit: cal yr BP # Core_Length: # Parameter_Keywords: nitrogen isotopes # Notes: #-------------------- # Chronology_Information # Chronology: # # # #------------------ # 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. # # variables format: shortname what,material,error,units,seasonality,data_type,detail,method, C(har) or N(umeric) data,additional information # ## depth_cm depth,,,centimeter,,paleoceanography,,,N, ## age_calkaBP age,,,calendar kiloyear before present,,paleoceanography,,,N, ## d15N delta 15N,sediment,,per mil,,paleoceanography,,,N, #-------------------- # Data: # Missing_Values: NaN depth_cm age_calkaBP d15N 0 8 10.6 6 9 11.2 11.5 11 10.4 16 11.5 11.2 21 13 10.7 28 13.5 11.1 33 14 10.8 38 14.5 11.1 44 16 9.8 50 19.5 10.4 55 20.5 10.4 61 25 10.4 66 26 11 71 29 10.6 75 30 10.5 80 33 10.5 85 34 10.4 89 36 10.2 94 38 9.8 109 47 10.2 114 49 11 119 52 10.9 125 54 10.3 131 56 10.2 137 62 9.6 142 68 9.4 148.5 70 9.3 154 76 9.1 160 79 8.9 166 80 9.3 171 81 9.7 177 82 10 182 83 9.1 187 84 9.4 198 87 9.1 204.5 93 8.7 216 96 8.8 222 98 9.2 228.5 102 9.5 235 106 9.1 241 111 9.3 247 116 9.1 253 120 9.9 258 124 10.2 264 129 10.5 269 130 9.9 275 131 9.3 282 132 9.8 287 138 9.5 292 141 9.3 296 147 9.2 301 153 9.5 306 155 9