# 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/ford2012odp853.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 853 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: ODP853 # Location: Ocean>Pacific Ocean>Eastern Pacific Ocean # Country: # Northernmost_Latitude: 7.211 # Southernmost_Latitude: 7.211 # Easternmost_Longitude: -109.7633 # Westernmost_Longitude: -109.7633 # Elevation: -3714 m #------------------ # Data_Collection # Core_Name: ODP853Ford2012 # First_Year: 5880000 # Last_Year: 0 # Time_Unit: Calendar Years before present # Core_Length: 35.18 m # Notes: #------------------ # Chronology # # # #------------------ # Variables # # 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) ## 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: # Missing Value: -999 # Data lines follow (have no #) # 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 0.2 0.000 1.94 0.76 1.343 17.4 853B1H1 20-22 0.35 0.040 1.49 1.37 1.390 17.7 853B1H1 35-37 0.5 0.085 1.87 1.21 1.390 17.7 853B1H1 50-52 0.66 0.134 1.47 1.45 1.252 16.6 853B1H1 66-68 0.83 0.186 1.66 0.95 1.123 15.4 853B1H1 83-85 0.97 0.229 1.31 1.50 1.296 17.0 853B1H1 97-99 0 0.269 -999 -999 1.256 16.6 853C1H1 0-2 1.12 0.275 1.35 1.85 1.226 16.3 853B1H1 112-114 0.15 0.314 -999 -999 1.273 16.8 853C1H1 15-17 1.27 0.320 2.09 1.40 1.510 18.7 853B1H1 127-129 0.3 0.360 1.42 1.08 1.247 16.5 853C1H1 30-32 1.42 0.366 1.76 1.68 1.565 19.1 853B1H1 142-144 1.5 0.391 1.62 1.06 1.426 18.0 853B1H2 0-2 0.45 0.406 1.46 1.35 1.269 16.7 853C1H1 45-47 1.7 0.452 1.69 1.37 1.371 17.6 853B1H2 20-22 0.6 0.452 1.43 1.39 1.343 17.4 853C1H1 60-62 0.73 0.491 1.37 1.52 1.438 18.1 853C1H1 73-75 1.86 0.500 1.71 0.89 1.329 17.2 853B1H2 36-38 2 0.541 1.61 0.69 1.822 20.8 853B1H2 50-52 0.9 0.541 1.76 1.00 1.168 15.8 853C1H1 90-92 2.15 0.586 1.39 2.04 -999 -999 853B1H2 65-67 2.15 0.586 1.40 2.02 1.251 16.6 853B1H2 65-67 1.05 0.586 1.55 1.34 -999 -999 853C1H1 105-107 1.05 0.586 1.58 1.37 1.194 16.1 853C1H1 105-107 2.3 0.630 1.31 1.10 1.279 16.8 853B1H2 80-82 1.2 0.630 1.67 0.37 1.424 18.0 853C1H1 120-122 2.45 0.675 1.41 0.74 1.917 21.3 853B1H2 95-97 1.35 0.675 1.48 1.54 1.299 17.0 853C1H1 135-137 2.61 0.710 1.43 1.57 1.481 18.4 853B1H2 111-113 2.75 0.739 1.05 1.71 1.245 16.5 853B1H2 125-127 2.9 0.770 1.21 1.71 1.184 16.0 853B1H2 140-142 3.01 0.794 1.35 1.80 1.731 20.2 853B1H3 1-3 3.17 0.831 1.37 1.43 1.373 17.6 853B1H3 17-19 3.3 0.862 1.13 2.00 1.261 16.7 853B1H3 30-32 3.47 0.901 1.22 1.22 1.195 16.1 853B1H3 47-49 3.58 0.927 1.37 1.12 1.269 16.7 853B1H3 58-60 3.78 0.974 1.54 0.82 1.226 16.4 853B1H3 78-80 3.93 1.009 1.35 0.92 1.344 17.4 853B1H3 93-95 4.07 1.042 1.25 1.28 1.771 20.4 853B1H3 107-109 4.31 1.084 1.35 1.54 1.661 19.7 853B2H1 1-3 4.45 1.111 1.46 1.19 1.854 21.0 853B2H1 15-17 4.6 1.140 1.48 1.24 1.350 17.4 853B2H1 30-32 4.75 1.169 1.27 1.45 1.290 16.9 853B2H1 45-47 4.88 1.194 1.42 0.77 1.506 18.6 853B2H1 58-60 5.03 1.223 1.05 1.71 1.357 17.5 853B2H1 73-75 5.19 1.254 1.35 1.20 1.527 18.8 853B2H1 89-91 5.35 1.285 1.31 1.16 1.309 17.1 853B2H1 105-107 5.49 1.312 1.26 1.16 1.172 15.9 853B2H1 119-121 5.65 1.343 1.34 1.21 1.614 19.4 853B2H1 135-137 5.81 1.374 1.46 1.03 1.651 19.7 853B2H2 1-3 5.95 1.402 1.47 1.38 1.446 18.2 853B2H2 15-17 6.12 1.435 1.39 1.07 1.546 18.9 853B2H2 32-34 6.25 1.460 1.51 1.04 1.417 18.0 853B2H2 45-47 6.38 1.485 1.30 0.39 1.284 16.9 853B2H2 58-60 6.54 1.516 1.50 0.71 1.429 18.1 853B2H2 74-76 6.68 1.543 1.59 0.79 1.480 18.4 853B2H2 88-90 6.85 1.576 1.61 0.84 1.565 19.1 853B2H2 105-107 6.98 1.601 1.40 0.54 1.752 20.3 853B2H2 118-120 7.15 1.634 1.24 0.98 1.570 19.1 853B2H2 135-137 7.31 1.665 1.19 1.06 1.748 20.3 853B2H3 1-3 7.45 1.692 1.30 1.00 1.204 16.1 853B2H3 15-17 7.45 1.692 -999 -999 1.204 16.1 853B2H3 15-17 7.75 1.751 1.28 0.84 1.608 19.4 853B2H3 45-47 7.88 1.777 1.25 1.06 2.131 22.5 853B2H3 58-60 8.03 1.812 1.10 1.35 1.421 18.0 853B2H3 73-75 8.17 1.845 1.35 1.36 1.706 20.0 853B2H3 87-89 8.35 1.887 1.51 1.02 1.455 18.3 853B2H3 105-107 8.48 1.917 1.43 1.46 1.170 15.8 853B2H3 118-120 8.65 1.955 1.53 0.91 1.455 18.3 853B2H3 135-137 8.81 1.984 1.35 1.27 1.392 17.8 853B2H4 1-3 9 2.018 1.59 0.43 1.379 17.7 853B2H4 20-22 9.1 2.036 1.60 0.09 1.474 18.4 853B2H4 30-32 9.25 2.063 1.20 1.01 1.372 17.6 853B2H4 45-47 9.38 2.087 1.52 0.68 1.357 17.5 853B2H4 58-60 9.55 2.117 1.47 0.52 1.538 18.9 853B2H4 75-77 9.67 2.139 1.37 0.80 1.481 18.5 853B2H4 87-89 9.86 2.173 1.22 0.85 1.550 19.0 853B2H4 106-108 10.02 2.202 1.28 0.14 2.106 22.4 853B2H4 122-124 10.15 2.225 1.50 0.56 1.451 18.2 853B2H4 135-137 10.3 2.252 1.39 0.57 1.508 18.6 853B2H5 0-2 10.74 2.332 1.65 0.52 1.676 19.8 853B2H5 44-46 10.89 2.359 1.55 0.34 1.588 19.2 853B2H5 59-61 11.04 2.386 1.64 0.67 1.384 17.7 853B2H5 74-76 11.16 2.407 1.77 0.42 1.268 16.7 853B2H5 86-88 11.37 2.445 1.27 0.19 1.558 19.0 853B2H5 107-109 11.48 2.465 1.50 0.38 1.695 19.9 853B2H5 118-120 11.66 2.497 1.28 0.36 1.448 18.2 853B2H5 136-138 11.81 2.524 1.19 0.04 1.572 19.1 853B2H6 1-3 12.25 2.603 1.55 -0.13 1.581 19.2 853B2H6 45-47 12.37 2.621 1.51 0.26 1.438 18.1 853B2H6 57-59 12.44 2.631 1.32 1.12 -999 -999 853B2H6 64-66 12.44 2.631 1.27 1.49 1.407 17.9 853B2H6 64-66 12.55 2.648 1.44 0.27 1.779 20.5 853B2H6 75-77 12.67 2.665 1.49 0.32 1.857 21.0 853B2H6 87-89 12.85 2.692 1.37 0.75 1.514 18.7 853B2H6 105-107 12.98 2.712 1.31 0.48 -999 -999 853B2H6 118-120 12.98 2.712 1.34 0.84 1.442 18.2 853B2H6 118-120 13.45 2.782 1.51 0.32 -999 -999 853B2H7 15-17 13.61 2.805 1.32 0.89 1.541 18.9 853B2H7 31-33 13.79 2.832 1.52 0.80 1.399 17.8 853B2H7 49-51 12.36 2.984 1.47 0.28 1.510 18.7 853B3H1 6-8 12.44 2.996 1.36 0.70 1.346 17.4 853B3H1 14-16 12.57 3.015 1.25 0.79 -999 -999 853B3H1 27-29 12.57 3.015 1.67 0.00 1.438 18.1 853B3H1 27-29 13.25 3.114 1.25 0.35 1.395 17.8 853B3H1 95-97 13.38 3.133 1.53 0.05 1.509 18.7 853B3H1 108-110 14.01 3.236 1.38 0.66 1.441 18.1 853B3H2 21-23 14.26 3.282 1.45 0.51 1.588 19.2 853B3H2 46-48 14.72 3.359 1.27 0.51 1.745 20.3 853B3H2 92-94 14.9 3.386 1.22 0.68 1.536 18.9 853B3H2 110-112 15.05 3.408 1.14 0.35 2.136 22.5 853B3H2 125-127 15.2 3.431 0.73 0.71 1.601 19.3 853B3H2 140-142 15.31 3.447 0.89 0.88 1.600 19.3 853B3H3 1-3 15.6 3.490 1.37 0.03 1.651 19.7 853B3H3 30-32 15.75 3.512 1.29 0.35 1.746 20.3 853B3H3 45-47 17 3.708 1.11 0.57 1.434 18.1 853B3H4 20-22 17.1 3.725 0.89 0.88 1.431 18.1 853B3H4 30-32 17.25 3.749 1.14 0.88 1.371 17.6 853B3H4 45-47 17.4 3.774 1.14 0.95 1.575 19.1 853B3H4 60-62 19.35 4.097 1.25 0.75 1.817 20.7 853B3H5 105-107 20.58 4.111 0.97 0.34 1.535 18.8 853B4H1 28-30 19.47 4.117 1.38 0.25 1.734 20.2 853B3H5 117-119 20.8 4.134 1.15 0.83 1.931 21.4 853B4H1 50-52 19.65 4.147 1.21 0.50 1.734 20.2 853B3H5 135-137 21.1 4.167 1.16 0.85 1.627 19.5 853B4H1 80-82 19.81 4.173 1.18 0.90 1.593 19.3 853B3H6 1-3 21.25 4.183 1.14 0.96 1.797 20.6 853B4H1 95-97 19.95 4.193 1.06 0.36 1.677 19.8 853B3H6 15-17 21.45 4.204 0.86 0.80 1.445 18.2 853B4H1 115-117 20.1 4.209 0.85 0.78 1.417 18.0 853B3H6 30-32 21.6 4.220 0.92 0.83 1.496 18.6 853B4H1 130-132 20.25 4.226 0.87 0.86 1.592 19.3 853B3H6 45-47 21.75 4.236 1.13 0.07 1.636 19.6 853B4H1 145-147 22.1 4.274 1.02 -0.82 1.755 20.3 853B4H2 30-32 20.8 4.285 1.09 0.50 1.765 20.4 853B3H6 100-102 22.25 4.290 1.29 -0.51 2.154 22.6 853B4H2 45-47 20.98 4.304 1.15 -0.20 2.036 22.0 853B3H6 118-120 22.41 4.307 1.28 -0.15 2.249 23.1 853B4H2 61-63 21.1 4.317 -999 -999 2.202 22.9 853B3H6 130-132 22.55 4.322 1.29 -0.21 2.125 22.5 853B4H2 75-77 22.68 4.332 -999 -999 2.113 22.4 853B4H2 88-90 22.85 4.345 1.25 0.02 1.600 19.3 853B4H2 105-107 22.98 4.355 -999 -999 1.785 20.5 853B4H2 118-120 23.15 4.368 1.44 0.23 1.814 20.7 853B4H2 135-137 23.45 4.391 1.34 0.08 1.687 19.9 853B4H3 15-17 23.6 4.403 1.35 -0.13 2.030 22.0 853B4H3 30-32 23.74 4.413 1.44 -0.72 1.799 20.6 853B4H3 44-46 24.65 4.534 1.19 -0.07 1.797 20.6 853B4H3 135-137 25.25 4.644 1.15 -0.22 1.994 21.8 853B4H4 45-47 25.85 4.725 1.44 -0.51 1.902 21.2 853B4H4 105-107 25.98 4.743 -999 -999 2.096 22.3 853B4H4 118-120 26.31 4.787 -999 -999 2.253 23.1 853B4H5 1-3 26.45 4.806 -999 -999 2.192 22.8 853B4H5 15-17 26.6 4.823 1.29 -0.78 -999 -999 853B4H5 30-32 26.91 4.858 -999 -999 1.890 21.2 853B4H5 61-63 27.48 4.933 1.63 -0.81 -999 -999 853B4H5 118-120 27.95 5.003 -999 -999 2.096 22.3 853B4H6 15-17 28.1 5.017 1.35 -0.33 1.837 20.8 853B4H6 30-32 28.25 5.031 1.31 -0.12 1.834 20.8 853B4H6 45-47 28.39 5.044 0.68 -0.51 -999 -999 853B4H6 59-61 28.67 5.070 -999 -999 2.030 22.0 853B4H6 87-89 28.6 5.289 -999 -999 2.072 22.2 853B5H1 30-32 28.75 5.303 1.58 -1.05 2.222 23.0 853B5H1 45-47 29.07 5.332 1.70 -1.11 -999 -999 853B5H1 77-79 29.19 5.342 1.70 -0.93 2.181 22.8 853B5H1 89-91 30.1 5.424 1.62 -0.64 2.258 23.1 853B5H2 30-32 30.4 5.451 -999 -999 2.073 22.2 853B5H2 60-62 31.01 5.506 -999 -999 1.827 20.8 853B5H2 121-123 31.15 5.518 -999 -999 1.945 21.5 853B5H2 135-137 31.45 5.545 -999 -999 2.237 23.0 853B5H3 15-17 31.92 5.588 -999 -999 1.818 20.7 853B5H3 62-64 32.33 5.624 1.82 -0.58 1.827 20.8 853B5H3 103-105 32.48 5.638 1.84 -0.66 2.251 23.1 853B5H3 118-120 32.64 5.652 -999 -999 2.115 22.4 853B5H3 134-136 33.76 5.753 -999 -999 1.969 21.6 853B5H4 96-98 35.18 5.880 -999 -999 1.913 21.3 853B5H5 88-90