http://lod.bco-dmo.org/id/dataset/806471
eng; USA
utf8
dataset
Highest level of data collection, from a common set of sensors or instrumentation, usually within the same research project
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
2020-03-19
ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
ISO 19115-2:2009(E)
234Th flux in epipelagic waters at Station ALOHA and the Equatorial Pacific from R/V Kilo Moana cruises KM1407, KM1418, & KM1515 during 2014-2015
2020-03-19
publication
2020-03-19
revision
Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA)
2020-03-31
publication
https://doi.org/10.26008/1912/bco-dmo.806471.1
Claudia R. Benitez-Nelson
University of South Carolina
principalInvestigator
Jeffrey C. Drazen
University of Hawaiʻi at Mānoa
principalInvestigator
Brian N. Popp
University of Hawaiʻi at Mānoa
principalInvestigator
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
publisher
Cite this dataset as: Benitez-Nelson, C., Drazen, J., Popp, B. (2020) 234Th flux in epipelagic waters at Station ALOHA and the Equatorial Pacific from R/V Kilo Moana cruises KM1407, KM1418, & KM1515 during 2014-2015. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2020-03-19 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.806471.1 [access date]
234Th flux in epipelagic waters of Station Aloha and the Equatorial North Pacific Dataset Description: Methods and Sampling: <p>Total ²³⁴Th was measured in samples of seawater collected at discrete depths using Niskin bottles as described in Umhau et al. (2019). Briefly, 2 L of seawater was collected at each selected depth. Samples were spiked with ²³⁰Th as a yield tracer and acidified to pH ~ 1 using concentrated nitric acid. After equilibration, ~ 6 hours later, KMnO₄ and MnCl₂ were added and the pH adjusted to ~ 9 with concentrated NH₄OH in order to co-precipitate Th via the formation of MnO₂. After eight hours, total ²³⁴Th samples were filtered onto 25 mm QMA filters, air dried, and frozen.</p>
<p>The ²³⁴Th flux (dpm m⁻² d⁻¹) was calculated from the ²³⁴Th:²³⁸U disequilibrium and assuming a steady state (Umhau et al. 2019). The ²³⁴Th flux at each depth was obtained by integrating the flux for the overlying depths using trapezoidal integration.</p>
<p>Thorium counts were made using a low level RISO beta counter within 2 weeks of sample collection.</p>
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1333734 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1333734
Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1433846 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1433846
completed
Claudia R. Benitez-Nelson
University of South Carolina
803-777-0525
School of the Earth, Ocean and Environment 701 Sumter Street
Columbia
SC
29208
USA
benitezn@mailbox.sc.edu
pointOfContact
Jeffrey C. Drazen
University of Hawaiʻi at Mānoa
808-956-6567
Department of Oceanography, SOEST 1000 Pope Road
Honolulu
HI
96822
USA
jdrazen@hawaii.edu
pointOfContact
Brian N. Popp
University of Hawaiʻi at Mānoa
808-956-6206
Department of Earth Sciences 1680 East-West Road
Honolulu
HI
96822
USA
popp@hawaii.edu
pointOfContact
asNeeded
Dataset Version: 1
Unknown
Cruise
Date_initial
Date_final
Site
Latitude
Longitude
Season
Depth
Th_flux
Th_flux_error
Niskin bottles
RISO beta counter
theme
None, User defined
Cruise identfier
date
site
latitude
longitude
season
depth
thorium-234 activity
featureType
BCO-DMO Standard Parameters
Niskin bottle
Riso Laboratory Anti-coincidence Beta Counter
instrument
BCO-DMO Standard Instruments
KM1407
KM1418
KM1515
service
Deployment Activity
Central North Pacific, Station ALOHA
Tropical Pacific
place
Locations
otherRestrictions
otherRestrictions
Access Constraints: none. Use Constraints: Please follow guidelines at: http://www.bco-dmo.org/terms-use Distribution liability: Under no circumstances shall BCO-DMO be liable for any direct, incidental, special, consequential, indirect, or punitive damages that result from the use of, or the inability to use, the materials in this data submission. If you are dissatisfied with any materials in this data submission your sole and exclusive remedy is to discontinue use.
Evaluating the relative importance of suspended and sinking particles to the meso and bathypelagic food web in the central North Pacific
https://osprey.bco-dmo.org/project/537123
Evaluating the relative importance of suspended and sinking particles to the meso and bathypelagic food web in the central North Pacific
<p><em>Description from NSF award abstract:</em><br />
The ocean's midwaters are the largest living space on the planet. The mesopelagic food web plays key roles in the biological carbon pump and the production of food for commercially harvested species, but its functioning is understudied because it is remote and technologically challenging to sample. Recent estimates indicate respiratory demand outstrips measured sinking particle supply by up to 2-3 orders of magnitude suggesting that some food inputs to the mesopelagic food web have been underestimated or missed. Suspended particles frequently are not sampled effectively and may be an overlooked food source. Because identifying the principal inputs of organic matter to the deep-sea food web is critical to understanding its function, the investigators propose to evaluate the relative importance of suspended and sinking particles to the meso- and bathypelagic food web in the central North Pacific. They will characterize the isotopic compositions of specific groups of mesopelagic and bathypelagic zooplankton and micronekton, and identify the extent to which they consume suspended or sinking particles using mass balance approaches. The investigators recently have recognized differences in delta 15N and delta 13C values of amino acids (AA) of sinking and suspended particles; these patterns diverge with depth, providing a means to distinguish between food web pathways. The research will define the source-specific isotopic values of suspended and sinking particles at several depths from the surface to the bathypelagic and test proposed microbial mechanisms driving these depth patterns. At corresponding depths, MOCNESS trawls will sample diverse metazoa: zooplankton size fractions, plus targeted resident, migrating and likely suspension-feeding taxa of zooplankton and micronekton. Preliminary data suggest that suspended particles are a secondary food source, containing less labile organic matter than sinking particles that exhibit a seasonal cycle in flux in the central North Pacific. This study will determine if suspended particles become more important to zooplankton and micronekton during a time of year when sinking particle flux is low (Jan/Feb) in comparison to when it is high (Aug), allowing an evaluation of how temporal change in surface ocean productivity affects the functioning of mesopelagic food webs.</p>
<p>Recent research has called for additional study of the ocean's deep midwaters. This study will provide new insights into the functioning of the meso- and bathypelagic food web and its coupling with surface ocean processes in the central North Pacific. The recently-demonstrated ecological tool of amino acid-specific isotopic analysis will provide a novel and comprehensive approach with which to address our hypotheses, and the project will develop the first AA isotopic dataset spanning particles to fish. Results will help identify the ecological underpinnings of increasing delta 15N values with depth in zooplankton -- apparently a common pattern. Zooplankton consumption of suspended particles also could constitute a mechanistic link between the microbial loop and higher trophic levels. The processes controlling the enormous attenuation of particle flux by mesopelagic consumers -- and thereby the strength of carbon sequestration to the deep ocean -- are not understood. Seasonal sampling will help us relate mesopelagic food web processes to changes in surface ocean productivity, furthering our understanding of future climate change impacts on deep-sea food webs and carbon flux. With regard to fisheries, many oceanic top predators such as tuna and swordfish feed on mesopelagic micronekton. A clearer understanding of the structure of mesopelagic food webs will help inform ecosystem models which are used to understand variation in fisheries production.</p>
SuspendSinkPart
largerWorkCitation
project
Collaborative Research: Isotopic insights to mercury in marine food webs and how it varies with ocean biogeochemistry
https://osprey.bco-dmo.org/project/560580
Collaborative Research: Isotopic insights to mercury in marine food webs and how it varies with ocean biogeochemistry
<p><em>NSF award abstract:</em><br />
Mercury is a pervasive trace element that exists in several states in the marine environment, including monomethylmercury (MMHg), a neurotoxin that bioaccumulates in marine organisms and poses a human health threat. Understanding the fate of mercury in the ocean and resulting impacts on ocean food webs requires understanding the mechanisms controlling the depths at which mercury chemical transformations occur. Preliminary mercury analyses on nine species of marine fish from the North Pacific Ocean indicated that intermediate waters are an important entry point for MMHg into open ocean food webs. To elucidate the process controlling this, researchers will examine mercury dynamics in regions with differing vertical dissolved oxygen profiles, which should influence depths of mercury transformation. Results of the study will aid in a better understanding of the pathways by which mercury enters the marine food chain and can ultimately impact humans. This project will provide training for graduate and undergraduate students, and spread awareness on oceanic mercury through public outreach and informal science programs.</p>
<p>Mercury isotopic variations can provide insight into a wide variety of environmental processes. Isotopic compositions of mercury display mass-dependent fractionation (MDF) during most biotic and abiotic chemical reactions and mass-independent fractionation (MIF) during photochemical radical pair reactions. The unusual combination of MDF and MIF can provide information on reaction pathways and the biogeochemical history of mercury. Results from preliminary research provide strong evidence that net MMHg formation occurred below the surface mixed layer in the pycnocline and suggested that MMHg in low oxygen intermediate waters is an important entry point for mercury into open ocean food webs. These findings highlight the critical need to understand how MMHg levels in marine biota will respond to changes in atmospheric mercury emissions, deposition of inorganic mercury to the surface ocean, and hypothesized future expansion of oxygen minimum zones. Using field collections across ecosystems with contrasting biogeochemistry and mercury isotope fractionation experiments researchers will fill key knowledge gaps in mercury biogeochemistry. Results of the proposed research will enable scientists to assess the biogeochemical controls on where in the water column mercury methylation and demethylation likely occur.</p>
<p><em>Related background publication with supplemental data section:</em><br />
Joel D. Blum, Brian N. Popp, Jeffrey C. Drazen, C. Anela Choy & Marcus W. Johnson. 2013. Methylmercury production below the mixed layer in the North Pacific Ocean. Nature Geoscience 6, 879–884. <a href="https://www.nature.com/articles/ngeo1918" target="_blank">doi:10.1038/ngeo1918</a></p>
Hg_Biogeochemistry
largerWorkCitation
project
eng; USA
oceans
Central North Pacific, Station ALOHA; Tropical Pacific
-158
-155
5
22
2014-02-19
2015-09-08
From projects that focused on the following 2 locations: 1. Subtropical waters north of Hawaii; Station Aloha (22° 45'N, 158° 00'W) 2. Pacific Subtropical Gyre, Station ALOHA 22.75N 158W; equatorial Pacific (10N 155W, 5N 155W)
0
BCO-DMO catalogue of parameters from 234Th flux in epipelagic waters at Station ALOHA and the Equatorial Pacific from R/V Kilo Moana cruises KM1407, KM1418, & KM1515 during 2014-2015
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
http://lod.bco-dmo.org/id/dataset-parameter/806489.rdf
Name: Cruise
Units: unitless
Description: <p>Cruise identifier</p>
http://lod.bco-dmo.org/id/dataset-parameter/806490.rdf
Name: Date_initial
Units: unitless
Description: <p>Sampling initial date (UTC); format: yyyy-mm-dd</p>
http://lod.bco-dmo.org/id/dataset-parameter/806491.rdf
Name: Date_final
Units: unitless
Description: <p>Sampling final date (UTC); format: yyyy-mm-dd</p>
http://lod.bco-dmo.org/id/dataset-parameter/806492.rdf
Name: Site
Units: unitless
Description: <p>Site identifier</p>
http://lod.bco-dmo.org/id/dataset-parameter/806493.rdf
Name: Latitude
Units: degrees N
Description: <p>Latitude</p>
http://lod.bco-dmo.org/id/dataset-parameter/806494.rdf
Name: Longitude
Units: degrees W
Description: <p>Longitude</p>
http://lod.bco-dmo.org/id/dataset-parameter/806495.rdf
Name: Season
Units: unitless
Description: <p>Season</p>
http://lod.bco-dmo.org/id/dataset-parameter/806496.rdf
Name: Depth
Units: meters (m)
Description: <p>Sampling depth</p>
http://lod.bco-dmo.org/id/dataset-parameter/806497.rdf
Name: Th_flux
Units: dpm m-2 d-1
Description: <p>Integrated 234Th flux; BD = below detection</p>
http://lod.bco-dmo.org/id/dataset-parameter/806498.rdf
Name: Th_flux_error
Units: dpm m-2 d-1
Description: <p>Integrated 234Th flux error</p>
GB/NERC/BODC > British Oceanographic Data Centre, Natural Environment Research Council, United Kingdom
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
1842
https://darchive.mblwhoilibrary.org/bitstream/1912/25602/1/dataset-806471_234th-flux__v1.tsv
download
https://doi.org/10.26008/1912/bco-dmo.806471.1
download
onLine
dataset
<p>Total ²³⁴Th was measured in samples of seawater collected at discrete depths using Niskin bottles as described in Umhau et al. (2019). Briefly, 2 L of seawater was collected at each selected depth. Samples were spiked with ²³⁰Th as a yield tracer and acidified to pH ~ 1 using concentrated nitric acid. After equilibration, ~ 6 hours later, KMnO₄ and MnCl₂ were added and the pH adjusted to ~ 9 with concentrated NH₄OH in order to co-precipitate Th via the formation of MnO₂. After eight hours, total ²³⁴Th samples were filtered onto 25 mm QMA filters, air dried, and frozen.</p>
<p>The ²³⁴Th flux (dpm m⁻² d⁻¹) was calculated from the ²³⁴Th:²³⁸U disequilibrium and assuming a steady state (Umhau et al. 2019). The ²³⁴Th flux at each depth was obtained by integrating the flux for the overlying depths using trapezoidal integration.</p>
<p>Thorium counts were made using a low level RISO beta counter within 2 weeks of sample collection.</p>
Specified by the Principal Investigator(s)
asNeeded
7.x-1.1
Biological and Chemical Oceanography Data Management Office (BCO-DMO)
Unavailable
508-289-2009
WHOI MS#36
Woods Hole
MA
02543
USA
info@bco-dmo.org
http://www.bco-dmo.org
Monday - Friday 8:00am - 5:00pm
For questions regarding this resource, please contact BCO-DMO via the email address provided.
pointOfContact
Niskin bottles
Niskin bottles
PI Supplied Instrument Name: Niskin bottles PI Supplied Instrument Description:Total 234Th was measured in samples of seawater collected at discrete depths using Niskin bottles. Instrument Name: Niskin bottle Instrument Short Name:Niskin bottle Instrument Description: A Niskin bottle (a next generation water sampler based on the Nansen bottle) is a cylindrical, non-metallic water collection device with stoppers at both ends. The bottles can be attached individually on a hydrowire or deployed in 12, 24, or 36 bottle Rosette systems mounted on a frame and combined with a CTD. Niskin bottles are used to collect discrete water samples for a range of measurements including pigments, nutrients, plankton, etc. Community Standard Description: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0412/
RISO beta counter
RISO beta counter
PI Supplied Instrument Name: RISO beta counter PI Supplied Instrument Description:Thorium counts were made using a low level RISO beta counter within 2 weeks of sample collection. Instrument Name: Riso Laboratory Anti-coincidence Beta Counter Instrument Short Name:Riso Beta Counter Instrument Description: Low-level beta detectors manufactured by Riso (now Nutech) in Denmark. These instruments accept samples that can be mounted on a 25mm filter holder. These detectors have very low backgrounds, 0.17 counts per minute, and can have counting efficiencies as high as 55%.
Typically used in laboratory analyses. Designed to measure low levels of beta particle emission. The systems work on the principle of anticoincidence.
Cruise: KM1407
KM1407
R/V Kilo Moana
Community Standard Description
International Council for the Exploration of the Sea
R/V Kilo Moana
vessel
KM1407
Jeffrey C. Drazen
University of Hawaiʻi at Mānoa
Cruise: KM1418
KM1418
R/V Kilo Moana
Community Standard Description
International Council for the Exploration of the Sea
R/V Kilo Moana
vessel
KM1418
Jeffrey C. Drazen
University of Hawaiʻi at Mānoa
Cruise: KM1515
KM1515
R/V Kilo Moana
Community Standard Description
International Council for the Exploration of the Sea
R/V Kilo Moana
vessel
KM1515
Brian N. Popp
University of Hawai'i
R/V Kilo Moana
Community Standard Description
International Council for the Exploration of the Sea
R/V Kilo Moana
vessel