# Eastern Equatorial Pacific Early Pliocene Mg/Ca Subsurface Temperature #----------------------------------------------------------------------- # World Data Center for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # NOTE: Please cite original reference when using these data, # plus the Online Resource and date accessed. # # # Online_Resource: http://hurricane.ncdc.noaa.gov/pls/paleox/f?p=519:1:::::P1_STUDY_ID:13538 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/ford2012/ford2012odp848.txt # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Paleoceanography #-------------------- # Contribution_Date # Date: 2012-11-13 #-------------------- # Title # Study_Name: Eastern Equatorial Pacific Early Pliocene Mg/Ca Subsurface Temperature #-------------------- # Investigators # Investigators: Ford, H.L.; Ravelo, A.C.; Hovan, S. #-------------------- # Description_and_Notes # Mg/Ca paleothermometry from the planktonic foraminifera Globorotalia tumida from the past ~5 Ma at Ocean Drilling Program (ODP) Site 848 in the eastern equatorial Pacific # #-------------------- # Publication # Authors: Heather L. Ford, A. Christina Ravelo, Steven Hovan # Published_Date_or_YEAR: 11-15-2012 # Published_Title: A deep Eastern Equatorial Pacific thermocline during the early Pliocene warm period # Journal_Name: Earth and Planetary Science Letters # Volume: 355-356 # Pages: 152-161 # DOI: 10.1016/j.epsl.2012.08.027 # Abstract: During the early Pliocene warm period (~4.6-4.2 Ma) in the Eastern Equatorial Pacific upwelling region, sea surface temperatures were warm in comparison to modern conditions. Warm upwelling regions have global effects on the heat budget and atmospheric circulation, and are argued to have contributed to Pliocene warmth. Though warm upwelling regions could be explained by weak winds and/or a deep thermocline, the temporal and spatial evolution of the equatorial thermocline is poorly understood. Here we reconstruct temporal and spatial changes in subsurface temperature to monitor thermocline depth and show the thermocline was deeper during the early Pliocene warm period than it is today. We measured subsurface temperature records from Eastern Equatorial Pacific ODP transect Sites 848, 849, and 853 using Mg/Ca records from Globorotalia tumida, which has a depth habitat of ~50-100 m. In the early Pliocene, subsurface temperatures were ~4-5°C warmer than modern temperatures, indicating the thermocline was relatively deep. Subsurface temperatures steeply cooled ~2-3°C from 4.8 to 4.0 Ma and continued to cool an additional 2-3°C from 4.0 Ma to present. Compared to records from other regions, the data suggests the pronounced subsurface cooling between 4.8 and 4.0 Ma was a regional signal related to restriction of the Isthmus of Panama, while continued cooling from 4.0 Ma to present was likely related to global processes that changed global thermocline structure. Additionally, the spatial evolution of the equatorial thermocline along a N-S transect across ODP Sites 853, 849 and 848 suggests an intensification of the southeast trades from the Pliocene to present. Large-scale atmospheric and oceanographic circulation processes link high and low latitude climate through their influence on equatorial thermocline source water regions and consequently the equatorial thermocline. Through these low latitude/high latitude linkages, changes in the equatorial thermocline and thermocline source water played an important role in the transition from the warm Pliocene to the cold Pleistocene. # #--------------------- # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: OCE-0902047, OCE-623419 #--------------------- # Funding_Agency_Name: IUP Senate Fellowship Program # Grant: #--------------------- # Funding_Agency_Name: Consortium for Ocean Leadership # Grant: Schlanger Fellowship #-------------------- # Site_Information # Site_Name: ODP848 # Location: Ocean>Pacific Ocean>Eastern Pacific Ocean # Country: # Northernmost_Latitude: -2.9938 # Southernmost_Latitude: -2.9938 # Easternmost_Longitude: -110.4798 # Westernmost_Longitude: -110.4798 # Elevation: -3856 m #------------------ # Data_Collection # Core_Name: ODP848Ford2012 # First_Year: 5424000 # Last_Year: 2000 # Time_Unit: Calendar Years before present # Core_Length: 54.5 m # Notes: #------------------ # Chronology # # # #------------------ # Variables # ## depth_m Depth (m), , , m, , , , , N ## age_calmaBP Age (calendar millions of years BP), , ,cal ma BP, , , , , N ## d13Cg.tumi delta C13 PDB (Globorotalia tumida), , , , , , , , N ## d18Og.tumi delta O18 PDB (Globorotalia tumida), , , , , , , , N ## Mg/Ca-g.tumi Magnesium/Calcium ratio (Globorotalia tumida), , , , , , , , N ## sst-sub Subsurface Sea Temperature (C), , , ,deg C, , , , N ## notes notes-Site Hole Core Type Section Interval-cm, , , , , , , , C # Data: # Data lines follow (have no #) # Data line variables format: Variables list, one per line, shortname-tab-longname-tab-longname components (9 components: material, error, units, anomaly, period, archive, detail, method, C or N for Character or Numeric data) # Data line format: tab-delimited text, variable short name as header depth_m age_calmaBP d13Cg.tumi d18Og.tumi Mg/Ca-g.tumi sst-sub notes 0.03 0.002 1.75 1.81 1.290 17.0 848B1H1 3-5 0.33 0.019 1.260 16.7 848B1H1 33-35 0.63 0.036 1.93 1.72 1.158 15.8 848B1H1 63-65 0.9 0.050 1.73 2.02 1.093 15.1 848B1H1 90-92 1.2 0.070 1.71 1.83 1.095 15.1 848B1H1 120-122 1.46 0.090 1.07 1.04 0.931 13.3 848B1H1 146-148 1.5 0.095 1.40 1.44 1.144 15.6 848B1H2 0-2 1.8 0.130 1.65 2.03 1.039 14.6 848B1H2 30-32 2.05 0.145 1.38 1.47 1.134 15.5 848B1H2 55-57 2.08 0.147 1.23 2.27 0.994 14.1 848B1HCC 0-2 2.2 0.155 1.29 1.91 1.272 16.8 848B2H1 0-2 2.5 0.174 1.43 1.93 1.069 14.9 848B2H1 30-32 2.76 0.200 1.68 1.69 1.156 15.8 848B2H1 56-58 3.1 0.244 1.463 18.4 848B2H1 90-92 3.42 0.264 1.66 1.72 1.166 15.8 848B2H1 122-124 3.65 0.276 1.712 20.1 848B2H1 145-147 3.7 0.280 1.58 2.19 1.168 15.9 848B2H2 0-2 4.01 0.311 1.092 15.1 848B2H2 31-33 4.26 0.330 1.48 1.77 1.205 16.2 848B2H2 56-58 4.64 0.346 1.88 1.74 1.214 16.3 848B2H2 94-96 4.92 0.359 1.315 17.2 848B2H2 122-124 5.2 0.372 1.62 1.30 1.290 17.0 848B2H3 0-2 5.51 0.388 1.605 19.4 848B2H3 31-33 5.8 0.414 1.061 14.8 848B2H3 60-62 6.1 0.428 1.21 1.46 1.104 15.2 848B2H3 90-92 6.43 0.442 1.48 1.41 1.118 15.4 848B2H3 123-125 6.7 0.455 1.273 16.8 848B2H4 0-2 7.02 0.470 1.47 1.83 1.324 17.3 848B2H4 32-34 7.36 0.488 0.83 2.44 1.191 16.1 848B2H4 66-68 7.6 0.502 1.24 1.62 1.146 15.7 848B2H4 90-92 7.93 0.528 1.32 1.13 848B2H4 123-125 7.93 0.528 1.60 1.51 1.182 16.0 848B2H4 123-125 8.15 0.539 0.73 0.94 848B2H4 145-147 8.15 0.539 1.09 1.33 1.252 16.6 848B2H4 145-147 8.2 0.541 1.297 17.0 848B2H5 0-2 8.51 0.556 1.66 1.89 1.250 16.6 848B2H5 31-33 8.8 0.570 1.40 2.19 1.308 17.1 848B2H5 60-62 9.1 0.592 1.25 2.51 1.215 16.3 848B2H5 90-92 9.42 0.619 1.43 2.08 0.946 13.5 848B2H5 122-124 9.66 0.629 1.33 1.46 1.186 16.0 848B2H5 146-148 9.7 0.631 1.21 1.47 1.173 15.9 848B2H6 0-2 10.01 0.644 1.50 2.25 1.060 14.8 848B2H6 31-33 10.26 0.655 1.45 2.22 1.167 15.9 848B2H6 56-58 10.6 0.671 1.42 0.94 1.607 19.4 848B2H6 90-92 11.2 0.708 1.11 2.46 1.054 14.7 848B2H7 0-2 11.52 0.727 1.09 1.51 1.054 14.7 848B2H7 32-34 11.7 0.737 1.44 1.05 1.223 16.4 848B3H1 0-2 11.76 0.741 1.22 1.69 1.174 15.9 848B2H7 56-58 12 0.758 1.34 1.39 1.248 16.6 848B3H1 30-32 12.05 0.762 0.78 1.53 1.257 16.7 848B2HCC 0-2 12.36 0.779 1.61 1.41 1.191 16.1 848B3H1 66-68 12.6 0.791 1.31 1.63 1.172 15.9 848B3H1 90-92 12.92 0.810 1.17 2.02 1.186 16.0 848B3H1 122-124 13.14 0.824 1.52 1.06 1.130 15.5 848B3H1 144-146 13.2 0.827 1.41 1.22 1.200 16.2 848B3H2 0-2 13.52 0.846 1.149 15.7 848B3H2 32-34 13.83 0.864 1.30 1.51 1.177 15.9 848B3H2 63-65 14.1 0.876 0.93 1.90 1.467 18.4 848B3H2 90-92 14.42 0.889 1.31 1.91 1.140 15.6 848B3H2 122-124 14.65 0.899 1.63 1.34 1.256 16.7 848B3H2 145-147 14.7 0.901 1.42 1.60 1.143 15.6 848B3H3 0-2 15 0.916 1.54 1.46 1.140 15.6 848B3H3 30-32 15.3 0.937 1.28 1.93 1.417 18.0 848B3H3 60-62 15.6 0.964 1.18 1.77 1.291 17.0 848B3H3 90-92 15.93 0.992 1.00 1.84 1.265 16.8 848B3H3 123-125 16.15 1.008 0.96 1.46 1.464 18.4 848B3H3 145-147 16.2 1.011 1.48 1.80 1.142 15.6 848B3H4 0-2 16.5 1.031 1.36 2.30 1.336 17.4 848B3H4 30-32 16.8 1.050 1.54 1.80 1.444 18.2 848B3H4 60-62 17.1 1.066 1.31 1.48 1.251 16.6 848B3H4 90-92 17.42 1.077 1.58 1.73 1.178 16.0 848B3H4 122-124 17.65 1.085 1.12 0.92 1.294 17.0 848B3H4 145-147 17.7 1.087 1.75 0.43 1.359 17.5 848B3H5 0-2 18 1.103 1.04 1.29 1.246 16.6 848B3H5 30-32 18.3 1.123 0.87 1.07 1.307 17.1 848B3H5 60-62 18.6 1.143 1.09 1.82 1.376 17.7 848B3H5 90-92 18.92 1.165 1.60 1.14 1.231 16.5 848B3H5 122-124 19.15 1.181 0.79 1.45 1.349 17.5 848B3H5 145-147 19.2 1.184 0.76 1.39 1.555 19.0 848B3H6 0-2 19.5 1.204 1.55 0.84 1.555 19.0 848B3H6 30-32 19.83 1.225 1.64 1.04 1.462 18.4 848B3H6 63-65 20.1 1.242 1.97 1.47 1.278 16.9 848B3H6 90-92 20.4 1.260 1.63 1.38 1.522 18.8 848B3H6 120-122 20.57 1.270 1.65 1.44 1.371 17.6 848B3H6 137-139 20.7 1.280 1.60 1.31 1.531 18.9 848B3H7 0-2 21.01 1.305 1.35 1.65 1.218 16.3 848B3H7 31-33 21.2 1.322 1.556 19.1 848B4H1 0-2 21.3 1.331 1.398 17.9 848B3H7 60-62 21.51 1.350 1.13 1.12 1.918 21.4 848B3HCC 0-2 21.51 1.350 1.349 17.5 848B4H1 31-33 21.8 1.374 1.46 1.57 1.242 16.5 848B4H1 60-62 22.1 1.388 1.52 2.70 1.127 15.5 848B4H1 90-92 22.96 1.439 1.258 16.7 848B4H2 26-28 23.3 1.473 1.137 15.6 848B4H2 60-62 23.6 1.504 1.163 15.8 848B4H2 90-92 23.9 1.535 1.41 1.28 1.520 18.8 848B4H2 120-122 24.15 1.556 1.10 1.46 1.335 17.4 848B4H2 145-147 24.22 1.562 1.07 1.79 1.236 16.5 848B4H3 2-4 24.5 1.613 1.521 18.8 848B4H3 30-32 24.8 1.646 1.26 1.63 1.169 15.9 848B4H3 60-62 25.1 1.678 1.57 1.90 1.299 17.0 848B4H3 90-92 25.4 1.706 1.71 1.31 848B4H3 120-122 25.4 1.706 1.72 0.92 1.508 18.7 848B4H3 120-122 25.65 1.741 1.34 1.26 1.462 18.4 848B4H3 145-147 25.72 1.752 1.41 1.21 1.613 19.5 848B4H4 2-4 26.33 1.804 1.40 1.03 1.632 19.6 848B4H4 63-65 26.6 1.832 1.38 1.32 1.393 17.8 848B4H4 90-92 26.92 1.866 0.95 2.04 1.551 19.0 848B4H4 122-124 27.14 1.894 1.78 0.93 1.294 17.0 848B4H4 144-146 27.2 1.902 1.69 0.69 1.393 17.8 848B4H5 0-2 27.46 1.950 1.49 0.83 848B4H5 26-28 27.46 1.950 1.70 0.47 1.677 19.9 848B4H5 26-28 27.83 2.016 1.28 1.75 1.338 17.4 848B4H5 63-65 28.1 2.054 1.41 1.11 1.216 16.3 848B4H5 90-92 28.43 2.087 1.56 1.67 848B4H5 123-126 28.43 2.087 1.51 1.60 1.263 16.7 848B4H5 123-126 28.65 2.110 1.37 1.48 1.299 17.0 848B4H5 145-147 28.7 2.124 1.45 1.49 1.192 16.1 848B4H6 0-2 28.96 2.188 1.26 1.44 1.187 16.0 848B4H6 26-28 29.3 2.285 1.37 1.34 1.309 17.1 848B4H6 60-62 29.6 2.347 1.40 1.15 1.191 16.1 848B4H6 90-92 29.92 2.391 1.35 0.80 848B4H6 122-124 30.16 2.441 1.66 0.92 1.149 15.7 848B4H6 146-148 30.2 2.448 1.51 1.45 1.283 16.9 848B4H7 0-2 30.46 2.493 1.42 1.40 1.319 17.2 848B4H7 26-28 30.7 2.534 1.48 1.54 848B5H1 0-2 30.7 2.534 1.41 1.20 1.315 17.2 848B5H1 0-2 30.84 2.560 1.21 1.13 1.289 17.0 848B4H7 64-66 30.96 2.582 1.223 16.4 848B5H1 26-28 30.97 2.584 1.40 1.15 1.550 19.0 848B4HCC 0-2 31.3 2.631 1.25 0.90 1.167 15.9 848B5H1 60-62 31.6 2.675 1.42 0.96 1.158 15.8 848B5H1 90-92 31.9 2.713 1.17 0.88 848B5H1 120-122 31.9 2.713 1.10 0.98 1.352 17.5 848B5H1 120-122 32.15 2.742 1.14 1.22 1.259 16.7 848B5H1 145-147 32.2 2.748 1.31 1.14 848B5H2 0-2 32.2 2.748 1.26 1.14 1.328 17.3 848B5H2 0-2 32.5 2.791 1.18 0.98 1.393 17.8 848B5H2 30-32 32.8 2.846 1.26 1.31 1.245 16.6 848B5H2 60-62 33.1 2.884 1.24 1.37 1.403 17.9 848B5H2 90-92 33.4 2.937 1.01 1.11 1.474 18.5 848B5H2 120-122 33.65 2.985 1.21 1.07 1.556 19.1 848B5H2 145-147 33.7 2.998 1.31 0.99 1.430 18.1 848B5H3 0-2 34 3.078 1.592 19.3 848B5H3 30-32 34.3 3.166 1.499 18.6 848B5H3 60-62 34.6 3.243 1.49 0.67 1.668 19.8 848B5H3 90-92 35.2 3.353 1.498 18.6 848B5H4 0-2 35.5 3.407 2.076 22.3 848B5H4 30-32 35.8 3.469 1.57 0.25 1.835 20.9 848B5H4 60-62 36.1 3.546 1.14 0.69 1.843 20.9 848B5H4 90-92 36.65 3.627 1.763 20.4 848B5H4 145-147 36.7 3.636 1.566 19.1 848B5H5 0-2 37 3.689 1.399 17.9 848B5H5 30-32 37.3 3.762 1.26 0.65 1.627 19.6 848B5H5 60-62 37.6 3.854 1.12 0.77 1.627 19.5 848B5H5 90-92 37.9 3.914 1.297 17.0 848B5H5 120-122 38.17 3.981 1.991 21.8 848B5H5 147-149 38.2 3.989 1.929 21.4 848B5H6 0-2 38.8 4.143 2.189 22.8 848B5H6 60-62 39.1 4.200 2.168 22.7 848B5H6 90-92 39.4 4.274 1.970 21.7 848B5H6 120-122 39.7 4.342 2.294 23.4 848B5H7 0-2 40.26 4.424 1.664 19.8 848B5HCC 0-2 40.5 4.461 1.639 19.6 848B6H1 30-32 40.8 4.505 1.21 0.72 1.924 21.4 848B6H1 60-62 41.1 4.543 1.909 21.3 848B6H1 90-92 41.4 4.575 1.564 19.1 848B6H1 120-122 41.65 4.590 1.828 20.8 848B6H1 145-147 41.7 4.591 1.461 18.4 848B6H2 0-2 42 4.603 2.026 22.0 848B6H2 30-32 42.6 4.639 1.877 21.1 848B6H2 90-92 42.9 4.657 2.059 22.2 848B6H2 120-122 43.15 4.673 1.14 0.73 848B6H2 145-147 43.15 4.673 1.27 0.51 1.791 20.6 848B6H2 145-147 43.2 4.676 1.27 0.70 1.583 19.2 848B6H3 0-2 43.8 4.714 1.651 19.7 848B6H3 60-62 44.1 4.733 2.008 21.9 848B6H3 90-92 44.65 4.763 2.643 24.9 848B6H3 145-147 44.7 4.765 2.537 24.5 848B6H4 0-2 45 4.791 1.657 19.8 848B6H4 30-32 45.9 4.860 1.424 18.1 848B6H4 120-122 46.15 4.877 1.14 0.08 2.310 23.4 848B6H4 145-147 46.5 4.906 2.143 22.6 848B6H5 30-32 46.8 4.932 1.48 0.67 848B6H5 60-62 46.8 4.932 1.47 0.71 848B6H5 60-62 47.1 4.958 1.46 0.65 2.489 24.3 848B6H5 90-92 47.4 4.983 2.537 24.5 848B6H5 120-122 48.9 5.120 2.573 24.6 848B6H6 120-122 51.17 5.260 1.46 0.70 848B7H1 147-149 51.2 5.261 1.56 0.49 2.294 23.4 848B7H2 0-2 51.5 5.275 2.027 22.0 848B7H2 30-32 52.4 5.317 2.624 24.9 848B7H2 120-122 52.7 5.330 1.60 0.50 2.571 24.6 848B7H3 0-2 53 5.345 2.054 22.1 848B7H3 30-32 54.5 5.424 2.590 24.7 848B7H4 30-32