# Central Equatorial Pacific Dust Flux, Productivity and d15N Data for 0-27ka
#-----------------------------------------------------------------------
#               World Data Center for Paleoclimatology, Boulder
#                                   and
#                      NOAA Paleoclimatology Program
#-----------------------------------------------------------------------
# NOTE: Please cite original publication, online resource and date accessed when using this data.
# If there is no publication information, please cite Investigator, title, online resource and date accessed.
#
# Description/Documentation lines begin with #
# Data lines have no #
#
# Online_Resource: https://www.ncdc.noaa.gov/paleo/study/
# Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/by_contributor/costa2015/costa2015-d15n.txt
#
# Archive: Paleoceanography
#
# Parameter_Keywords: geochemistry, lithology, nitrogen isotopes
#---------------------------------------
# Contribution_Date
#    Date: 2015-11-10
#---------------------------------------
# Title
#    Study_Name: Central Equatorial Pacific Dust Flux, Productivity and d15N Data for 0-27ka
#---------------------------------------
# Investigators
#      Investigators: Costa, K.M.; McManus, J.F.; Anderson, R.F.; Ren, H.; Sigman, D.M.; Winckler, G.; Fleisher, M.Q.; Marcantonio, F.; Ravelo, A.C.
#---------------------------------------
# Description and Notes
#        Description: Site Information:
# MC # BB # Lat(N) Long(W) Depth(m)
# 14 13 -0.22 156 3049
# 21 20 1.27 157.3 2850
# 26 25 2.46 159.4 3545
# 29 28 2.97 159.2 3152
# 33 32 5.2 160.4 2933
# 39 36 6.83 161 2859
#         Provided Keywords: Holocene, Last Glacial Period, dust, productivity, Th isotopes, opal, barium
#---------------------------------------
# Publication
# Authors: Costa, K.M.; McManus, J.F.; Anderson, R.F.; Ren, H.; Sigman, D.M.; Winckler, G.; Fleisher, M.Q.; Marcantonio, F. and Ravelo, A.C.
# Published_Date_or_Year: 2015
# Published_Title: No iron fertilization in the Equatorial Pacific during the Last Ice Age
# Journal_Name: Nature
# Volume: 529
# Issue: 
# Pages: 519-522
# Report Number: 
# DOI: 
# Abstract: The “major” nutrients for phytoplankton growth (nitrogen, phosphorus, and silicon) are supplied to the surface waters of the Equatorial Pacific (EP) by wind-driven upwelling along the equator. Their consumption by phytoplankton is thought to be limited in part by the low concentrations of the critical micro-nutrient iron. Greater atmospheric dust deposition may have fertilized the EP with iron during the Last Glacial Period (LGP, 17-27,000 years ago). Here we present meridional transects of dust (232Th), phytoplankton productivity (opal, 231Pa/230Th, excess Ba), and the degree of nitrate consumption (foraminifera-bound d15N) from the Central EP for Holocene and LGP time slices. Despite two- to three-fold greater dust deposition in the Central EP, productivity was the same or lower during the LGP compared to the Holocene, and the degree of nitrate consumption was unchanged. These biogeochemical findings suggest that the relatively greater ice age dust fluxes were inadequate to drive significant iron fertilization in the Central EP, which may be because the absolute rate of dust deposition in the LGP, despite being greater than the Holocene rate, was still very low. The lower productivity coupled with unchanged nitrate consumption suggests lower subsurface major nutrient concentrations in the Central EP during the LGP. As these nutrients are today dominantly sourced from the Subantarctic Zone of the Southern Ocean, the Central EP data are consistent with more complete nutrient consumption in the Subantarctic, apparently because of iron fertilization in that region, where absolute dust fluxes were much higher. Thus, ice age iron fertilization ultimately worked to lower, not raise, Equatorial Pacific productivity.
#---------------------------------------
# Funding_Agency
#    Funding_Agency_Name: National Science Foundation
#    Grant: AGS-15-02889, OCE-10-60947
#---------------------------------------
# Site Information
# Site_Name: Line Islands
# Location: Central Equatorial Pacific
# Country: 
# Northernmost_Latitude: 6.83
# Southernmost_Latitude: -0.22
# Easternmost_Longitude: -156
# Westernmost_Longitude: -161
# Elevation: -2850
#---------------------------------------
# Data_Collection
#   Collection_Name: Line Island d15N Costa15
#   First_Year: 27000
#   Last_Year: 2000
#   Time_Unit: cal yr BP
#   Core_Length: 
#   Notes: 
#---------------------------------------
# Chronology: 
# 
# Core	Depth (cm)	Radiocarbon Age (yrs)	±	Calendar Age (yrs)	±	
# 14MC	0	3460	35	3340	110	
# 14MC	8	5770	30	6200	90	
# 13BB	34	14580	40	17260	180	
# 13BB	53	20760	70	24440	250	
# 
# 21MC	0	2330	25	1950	80	
# 21MC	8	3500	35	3390	110	
# 20BB	40	14685	40	17400	200	
# 20BB	55	19100	70	22540	160	
# 
# 26MC	0	3900	35	3880	130	
# 26MC	8	4740	35	4980	130	
# 25BB	25	15950	60	18800	140	
# 25BB	35	22400	100	26200	230	
# 
# 29MC	0	4200	15	4300	80	
# 29MC	8	4770	20	5020	110	
# 28BB	54	16600	60	19550	220	
# 28BB	76	25400	160	29030	360	
# 
# 33MC	0	4930	35	5270	150	
# 33MC	8	5260	20	5610	40	
# 32BB	25	15350	75	18170	220	
# 32BB	35	19300	75	22750	240	
# 
# 39MC	0	4730	45	4960	130	
# 39MC	8	5800	20	6230	80	
# 36BB	15	11650	25	13150	140	
# 36BB	25	16700	90	19670	190	
# 
#---------------------------------------
# Variables
# Data variables follow that are preceded by "##" in columns one and two.
# Variables list, one per line, shortname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data)
## SampleID	Sample ID,,,NA,,,,,C
## Time_Slice	Time Slice name,,,NA,,,,,C
## lat_N	latitude,,,degrees N,,Paleoceanography,, ,N
## d15Ng.rub-avg	delta 15N,Globigerinoides ruber,,per mil,,Paleoceanography,average, ,N
## d15Ng.rub-avg_err2s	delta 15N,Globigerinoides ruber,2sigma error,per mil,,Paleoceanography,average, ,N
## d15Ng.sac-avg	delta 15N,Globigerinoides sacculifer,,per mil,,Paleoceanography,average, ,N
## d15Ng.sac-avg_err2s	delta 15N,Globigerinoides sacculifer,2sigma error,per mil,,Paleoceanography,average, ,N
## d15Ng.tum-avg	delta 15N,Globorotalia tumida,,per mil,,Paleoceanography,average, ,N
## d15Ng.tum-avg_err2s	delta 15N,Globorotalia tumida,2sigma error,per mil,,Paleoceanography,average, ,N
#------------------------
# Data
# Data lines follow (have no #)
# Data line format - tab-delimited text, variable short name as header
# Missing Value: NaN
SampleID	Time_Slice	lat_N	d15Ng.rub-avg	d15Ng.rub-avg_err2s	d15Ng.sac-avg	d15Ng.sac-avg_err2s	d15Ng.tum-avg	d15Ng.tum-avg_err2s	
14MC: 0-8	Holocene	-0.22	5.01	NaN	6.13	0.51	8.35	0.75	
21MC: 0-8	Holocene	1.27	6.00	NaN	7.20	0.74	8.45	0.06	
26MC: 0-8	Holocene	2.46	NaN	NaN	6.99	NaN	9.17	0.50	
29MC: 0-8	Holocene	2.97	6.59	NaN	6.85	0.51	8.80	0.32	
33MC: 0-8	Holocene	5.20	8.68	NaN	9.57	0.31	10.83	0.23	
39MC: 0-8	Holocene	6.83	11.03	NaN	11.50	0.27	13.33	0.01	
13BB: 39, 45	LGP	-0.22	4.90	0.07	6.21	0.70	8.29	0.35	
20BB: 50, 51	LGP	1.27	5.41	0.16	6.89	0.29	8.67	0.15	
25BB: 25, 30	LGP	2.46	6.76	0.34	6.91	0.80	8.41	0.80	
28BB: 54, 65	LGP	2.97	6.49	1.26	7.31	0.58	9.01	1.16	
32BB: 30, 31	LGP	5.20	8.26	0.64	9.02	0.59	10.66	0.55	
36BB: 25, 29	LGP	6.83	9.99	0.52	11.39	1.12	13.65	0.40