# Deep Pacific 22,000 Year D14C Data and Projection Ventilation Ages 
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#                World Data Service for Paleoclimatology, Boulder 
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#                     NOAA Paleoclimatology Program 
#             National Centers for Environmental Information (NCEI)
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# Template Version 3.0
# Encoding: UTF-8
# NOTE: Please cite Publication, and Online_Resource and date accessed when using these data. 
# If there is no publication information, please cite Investigators, Title, and Online_Resource and date accessed. 
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# Online_Resource: https://www.ncdc.noaa.gov/paleo/study/25110 
#       Description: NOAA Landing Page
# Online_Resource: https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/lund2013/lund2013-13pc-proj-age-err.txt
#       Description: NOAA location of the template
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# Original_Source_URL:  
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# Description/Documentation lines begin with #
# Data lines have no #
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# Archive: Paleoceanography
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# Dataset DOI: 
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# Parameter_Keywords: age control, carbon isotopes
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# Contribution_Date
#	Date: 2018-09-07
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# File_Last_Modified_Date
#	Date: 2018-09-07
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# Title
#	Study_Name: Deep Pacific 22,000 Year D14C Data and Projection Ventilation Ages 
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# Investigators
#	Investigators: Lund, D.C.
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# Description_Notes_and_Keywords
#	Description: Deep Pacific ventilation ages estimated from D14C using revised projection age and TTD-ETD methods on 4 Pacific Ocean sediment cores for the past 22,000 years.
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# Publication 
#	Authors: David C.Lund
#	Published_Date_or_Year: 2013-11-01      
#	Published_Title: Deep Pacific ventilation ages during the last deglaciation: Evaluating the influence of diffusive mixing and source region reservoir age 
#	Journal_Name: Earth and Planetary Science Letters
#	Volume: 381
#	Edition: 
#	Issue: 
#	Pages: 52-62
#	Report_Number: 
#	DOI: 10.1016/j.epsl.2013.08.032
#	Online_Resource: https://www.sciencedirect.com/science/article/pii/S0012821X1300469X
#	Full_Citation: 
#	Abstract: Enhanced ventilation of the deep ocean during the last deglaciation may have caused the rise in atmospheric carbon dioxide that drove Earth's climate from a glacial to interglacial state. Recent results based on the projection age method, however, suggest the ventilation rate of the deep Pacific slowed during the deglaciation, opposite the expected pattern (Lund et al., 2011). Because the projection age method does not account for tracer diffusion (Adkins and Boyle, 1997) it can yield spurious results and therefore requires validation with alternative techniques. Here ventilation ages are determined using the transit-time equilibration-time distribution (TTD-ETD) method which explicitly accounts for diffusive mixing in the ocean interior (DeVries and Primeau, 2010). The overall time history of deep Pacific TTD-ETD and projection ages is very similar; both show a 1000-yr increase in ventilation age during Heinrich Stadial 1 (HS1; 14.5-17.5 kyr BP) and a 500-yr increase during the Younger Dryas (YD). The similarity is due in part to the use of projection age error estimates that take into account uncertainty in both calendar age and benthic 14C age. Centennial-scale offsets between the TTD-ETD and projection ages are due primarily to the different approaches used to estimate surface ocean radiocarbon content. Both the TTD-ETD and projection age results imply that the ventilation rate of the deep Pacific decreased during the deglaciation, opposite the pattern expected if Southern Ocean upwelling and enhanced meridional overturning drove outgassing of CO2 from the abyss. Variations in surface water reservoir age could cause an apparent shift in deep Pacific ventilation age but existing proxy records from the Southern Ocean appear to be inconsistent with such a driver.
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# Funding_Agency 
#	Funding_Agency_Name: University of Michigan
#	Grant: 
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# Site_Information 
#	Site_Name: W8709A-13PC
#	Location: Ocean>Pacific Ocean>North Pacific Ocean
#	Country:  
#	Northernmost_Latitude: 42.1
# 	Southernmost_Latitude: 42.1
# 	Easternmost_Longitude: -125.8
# 	Westernmost_Longitude: -125.8
# 	Elevation: -2710 m
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# Data_Collection   
#	Collection_Name: Lund2013-13PC-proj-age-err
#	Earliest_Year: 22920
#	Most_Recent_Year: 40
#	Time_Unit: Cal. Year BP
#	Core_Length: 
#	Notes: 
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# Chronology_Information
#	Chronology: 
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# Variables 
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# Data variables follow are preceded by "##" in columns one and two.
# Data line variables format:  one per line, shortname-tab-variable components (what, material, error, units, seasonality, data type,detail, method, C or N for Character or Numeric data, free text) 
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## age_calkaBP+	age, , , calendar Kyears before present, , , , ,N,
## age_proj+	Projection age upper, , , years, , , , ,N,
## age_calkaBP-	age, , , calendar Kyears before present, , , , ,N,
## age_proj-	Projection age lower, , , years, , , , ,N,
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# Data:
# Data lines follow (have no #)
# Data line format - tab-delimited text, variable short name as header
# Missing Values:  
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age_calkaBP+	age_proj+	age_calkaBP-	age_proj-
0.040	1351.303	0.060	1272.649
8.118	1685.579	8.560	1201.603
8.639	1669.340	9.204	1086.992
8.981	1516.960	9.449	1035.853
9.559	1634.751	10.079	1112.375
9.718	1603.019	10.283	1025.575
10.205	2232.342	10.706	1699.906
10.139	2554.701	10.924	1722.619
11.201	2070.879	11.865	1398.905
11.069	2180.794	11.718	1530.522
11.627	1937.060	12.369	1185.486
12.009	1702.196	12.585	1107.872
11.608	2148.579	12.371	1384.009
12.595	1570.332	12.973	1182.806
12.943	2298.435	13.366	1853.549
13.424	3092.470	13.812	2689.830
13.574	3171.656	14.150	2578.498
13.815	3236.510	14.634	2286.914
14.013	2842.954	14.668	2183.814
15.096	1983.558	16.092	974.294
15.222	2283.497	16.198	1298.511
15.865	2639.304	16.752	1650.838
15.849	2121.873	16.731	1210.721
15.808	2544.264	16.697	1390.689
16.639	1915.529	17.084	1471.447
16.799	1891.177	17.226	1454.383
16.938	2044.110	17.441	1506.358
17.410	1998.640	17.972	1415.975
17.675	1742.154	18.468	931.124
17.906	1641.081	18.509	978.777
18.923	2235.256	19.387	1372.344
18.975	2387.649	19.820	1441.897
20.150	1874.958	20.937	946.698
22.228	2560.065	22.920	1762.019