http://lod.bco-dmo.org/id/dataset/948358 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 2025-01-13 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) Nitrate 15N/14N measurements in two adjacent mesoscale eddies in the North Pacific Subtropical Gyre from water samples collected on R/V Kilo Moana cruise KM1709 in June-July 2017 2025-01-13 publication 2025-01-13 revision Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA) 2025-01-16 publication https://doi.org/10.26008/1912/bco-dmo.948358.1 Julie Granger University of Connecticut principalInvestigator Benedetto Barone University of Hawai'i principalInvestigator Angelicque E. White 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: Zhou, M., Granger, J., Barone, B., White, A. E. (2025) Nitrate 15N/14N measurements in two adjacent mesoscale eddies in the North Pacific Subtropical Gyre from water samples collected on R/V Kilo Moana cruise KM1709 in June-July 2017. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2025-01-13 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.948358.1 [access date] Nitrate 15N/14N measurements in two adjacent mesoscale eddies in the North Pacific Subtropical Gyre Dataset Description: Methods and Sampling: &lt;p&gt;Water was collected during the MESO-SCOPE research cruise aboard R/V Kilo Moana (KM1709) during June-July 2017. Upper ocean biogeochemistry was characterized at 11 stations along the transect traversing the cyclonic and anticyclonic eddies, using a rosette mounted with 10-liter (L) Niskin® bottles. Water samples for nutrient and nitrate isotope analyses were collected at ~25-meter (m) intervals from 5 m to 500 m with higher vertical resolution (~5 m intervals) near the deep chlorophyll maximum (DCM). Samples were frozen at -20 degrees Celsius (°C) after collection pending analysis.&lt;/p&gt; &lt;p&gt;The N isotope ratios of nitrate (15N/14N) in water samples from stations 4 to 13 were measured with the denitrifier method (Casciotti et al., 2002; Sigman et al., 2001) for concentrations exceeding 0.5 micromoles per liter (µmol L-1). Nitrate was converted to nitrous oxide (N2O) by cell concentrates of the denitrifying bacterial strain &lt;em&gt;Pseudomonas chlororaphis&lt;/em&gt; (ATCC 43928, Manassas, VA, USA), which lacks the terminal N2O reductase. The N2O gas was extracted and purified using a custom-modified Thermo Fisher Scientific Gas Bench II fronted by dual cold traps and a GC Pal autosampler, and analyzed with a Thermo Delta V Advantage continuous flow gas chromatograph isotope ratio mass spectrometer (Casciotti et al., 2002; McIlvin &amp;amp; Casciotti, 2011). Working solutions were diluted from primary stocks into nutrient-free seawater to concentrations bracketing sample concentrations to account for potential matrix effects (Weigand et al., 2016; Zhou et al., 2021). Individual samples were measured 3 to 9 times to achieve an analytical uncertainty to ≤ 0.3 ‰. The oxygen isotope ratios of nitrate (ẟ18ONO3) were not measured concurrently as we did not secure sufficient sample volumes to estimate these reliably (see Zhou et al., 2021).&lt;/p&gt; Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1554474 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1554474 Funding provided by Simons Foundation (Simons) Award Number: 329104 completed Julie Granger University of Connecticut 860-405-9094 Department of Marine Sciences 1080 Shenecossett Road Groton CT 06340 USA julie.granger@uconn.edu pointOfContact Benedetto Barone University of Hawai'i 808-956-8779 1050 East West Road Honolulu HI 96822 USA bbarone@hawaii.edu pointOfContact Angelicque E. White University of Hawaiʻi at Mānoa 808-956-6220 1950 East West Rd. Honolulu HI USA aewhite@hawaii.edu pointOfContact asNeeded Dataset Version: 1 Unknown ISO_DateTime_Local_HST ISO_DateTime_UTC Latitude Longitude Station Depth Mean_d15NNO3 Stdev_d15NNO3 GC Pal autosampler 10 L Niskins Thermo Delta V Advantage continuous flow gas chromatograph isotope ratio mass spectrometer Thermo Fisher Scientific Gas Bench II theme None, User defined ISO_DateTime_Local ISO_DateTime_UTC latitude longitude station depth d15N_NO3 featureType BCO-DMO Standard Parameters Laboratory Autosampler Niskin bottle Thermo Fisher Scientific DELTA V Advantage isotope ratio mass spectrometer Thermo-Fisher Scientific Gas Bench II instrument BCO-DMO Standard Instruments KM1709 service Deployment Activity North of the Hawaiian Islands 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. CAREER: The biological nitrogen isotope systematics of ammonium consumption and production https://osprey.bco-dmo.org/project/856532 CAREER: The biological nitrogen isotope systematics of ammonium consumption and production <p><strong>NSF Award Abstract:</strong><br /> The nitrogen (N) cycle in the marine environment is controlled by biological processes. Unfortunately, quantifying these processes and assessing their effect on the N cycle is difficult by direct measurements because of large spatial and temporal differences. Isotopic composition measurements of N provide a means to constrain these processes indirectly; however, there is still a great deal to be understood about isotope fractionation of recycled nitrogen through biological processes, which has made interpretation of novel nitrogen isotope data difficult. A researcher from the University of Connecticut plans to determine the influence of biological consumption and production on the isotope fractionation in ammonium. By helping to understand the processes surrounding fractionation of recycled ammonium at the organism level, this research will create a basis for which future researchers can better interpret isotope composition data to infer nitrogen cycle dynamics. A graduate student, a postdoctoral fellow, and two or more undergraduate students will be involved in the research. The researcher plans to integrate science with community-engaged learning by developing an undergraduate field and laboratory course that will require the students to present their research to stakeholders in the community. There will be a manual created for this course that will be disseminated in open-access forums for teachers hoping to develop similar courses.</p> <p>Biological nitrogen isotope fractionation associated with nitrogen recycling remains poorly constrained despite the advent of a variety of new techniques to analyze nitrogen isotopes in recent years. The use of isotopic composition data can be incredibly useful to interpreting nitrogen cycle processes in the ocean that are difficult to measure directly, which makes it crucial to further understand the processes behind fractionation to catch up with the advancement of the datasets available to researchers. This research will characterize the isotope fractionation dynamics of ammonium during biological consumption and production. The researchers will investigate whether the characteristic low concentrations of ammonium in the surface ocean affect isotope fractionation when the ammonium is recycled and whether there is a trophic isotope effect associated with ammonium recycling by protozoan grazers. With this research, there will be a baseline from which researchers can interpret recycled nitrogen dynamics from ammonium isotope datasets. The methods of comparing nitrogen cycling studies will become significantly clearer with such a standard making interpretation uniform by removing significant uncertainties.</p> Biological Nitrogen Isotope Fractionation largerWorkCitation project eng; USA oceans North of the Hawaiian Islands -158.72 -157.28 24.47 27.95 2017-06-29 2017-07-01 0 BCO-DMO catalogue of parameters from Nitrate 15N/14N measurements in two adjacent mesoscale eddies in the North Pacific Subtropical Gyre from water samples collected on R/V Kilo Moana cruise KM1709 in June-July 2017 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/948545.rdf Name: ISO_DateTime_Local_HST Units: unitless Description: <p>Date and time of sample collection in the local time zone (HST); in ISO 8601 format</p> http://lod.bco-dmo.org/id/dataset-parameter/948546.rdf Name: ISO_DateTime_UTC Units: unitless Description: <p>Date and time (UTC) of sample collection; in ISO 8601 format</p> http://lod.bco-dmo.org/id/dataset-parameter/948547.rdf Name: Latitude Units: decimal degrees Description: <p>Latitude of sample collection</p> http://lod.bco-dmo.org/id/dataset-parameter/948548.rdf Name: Longitude Units: decimal degrees Description: <p>Longitude of sample collection; negative values = West</p> http://lod.bco-dmo.org/id/dataset-parameter/948549.rdf Name: Station Units: unitless Description: <p>Station number</p> http://lod.bco-dmo.org/id/dataset-parameter/948550.rdf Name: Depth Units: meters (m) Description: <p>Sample depth</p> http://lod.bco-dmo.org/id/dataset-parameter/948551.rdf Name: Mean_d15NNO3 Units: ‰ vs. air Description: <p>Mean of the ẟ15NNO3 measurements for each sample</p> http://lod.bco-dmo.org/id/dataset-parameter/948552.rdf Name: Stdev_d15NNO3 Units: ‰ vs. air Description: <p>Standard deviation of the ẟ15NNO3 measurements for each sample</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 2385 https://darchive.mblwhoilibrary.org/server/api/core/bitstreams/e6986ec4-9808-4889-899a-896e92d59324/content download https://doi.org/10.26008/1912/bco-dmo.948358.1 download onLine dataset &lt;p&gt;Water was collected during the MESO-SCOPE research cruise aboard R/V Kilo Moana (KM1709) during June-July 2017. Upper ocean biogeochemistry was characterized at 11 stations along the transect traversing the cyclonic and anticyclonic eddies, using a rosette mounted with 10-liter (L) Niskin® bottles. Water samples for nutrient and nitrate isotope analyses were collected at ~25-meter (m) intervals from 5 m to 500 m with higher vertical resolution (~5 m intervals) near the deep chlorophyll maximum (DCM). Samples were frozen at -20 degrees Celsius (°C) after collection pending analysis.&lt;/p&gt; &lt;p&gt;The N isotope ratios of nitrate (15N/14N) in water samples from stations 4 to 13 were measured with the denitrifier method (Casciotti et al., 2002; Sigman et al., 2001) for concentrations exceeding 0.5 micromoles per liter (µmol L-1). Nitrate was converted to nitrous oxide (N2O) by cell concentrates of the denitrifying bacterial strain &lt;em&gt;Pseudomonas chlororaphis&lt;/em&gt; (ATCC 43928, Manassas, VA, USA), which lacks the terminal N2O reductase. The N2O gas was extracted and purified using a custom-modified Thermo Fisher Scientific Gas Bench II fronted by dual cold traps and a GC Pal autosampler, and analyzed with a Thermo Delta V Advantage continuous flow gas chromatograph isotope ratio mass spectrometer (Casciotti et al., 2002; McIlvin &amp;amp; Casciotti, 2011). Working solutions were diluted from primary stocks into nutrient-free seawater to concentrations bracketing sample concentrations to account for potential matrix effects (Weigand et al., 2016; Zhou et al., 2021). Individual samples were measured 3 to 9 times to achieve an analytical uncertainty to ≤ 0.3 ‰. The oxygen isotope ratios of nitrate (ẟ18ONO3) were not measured concurrently as we did not secure sufficient sample volumes to estimate these reliably (see Zhou et al., 2021).&lt;/p&gt; Specified by the Principal Investigator(s) &lt;p&gt;The N isotope ratios are expressed in delta (ẟ) notation in units of per mil (‰) vs. a standard material (N2 gas in the air): ẟ15Nsample = [(15N/14N)sample/(15N/14N)standard – 1] × 1000. Nitrate isotopic analyses were calibrated to internationally recognized nitrate reference materials IAEA-NO3 (International Atomic Energy Agency, Vienna, Austria) and USGS-34 (National Institute of Standards and Technology, Gaithersburg, MD, USA), with reported δ15N values of 4.7 ‰ and −1.8 ‰ (vs. air). Individual samples were measured 3 - 9 times to achieve an analytical uncertainty to ≤ 0.3 ‰.&lt;/p&gt; Specified by the Principal Investigator(s) - Imported original file &quot;Zhou_etal-BCO-DMO.xlsx&quot; into the BCO-DMO submission. - Renamed fields to comply with BCO-DMO naming conventions. - Created ISO-DateTime fields in local (HST) and UTC format. - Removed the original, separate date and time columns. - Converted longitude values from positive to negative to indicate the direction is West. - Saved the final file as &quot;948358_v1_nitrate_15n_14n_meso-scope.csv&quot;. Specified by BCO-DMO Data Managers 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 GC Pal autosampler GC Pal autosampler PI Supplied Instrument Name: GC Pal autosampler PI Supplied Instrument Description:a custom-modified Thermo Fisher Scientific Gas Bench II fronted by dual cold traps and a GC Pal autosampler, and analyzed with a Thermo Delta V Advantage continuous flow gas chromatograph isotope ratio mass spectrometer Instrument Name: Laboratory Autosampler Instrument Short Name: Instrument Description: Laboratory apparatus that automatically introduces one or more samples with a predetermined volume or mass into an analytical instrument. 10 L Niskins 10 L Niskins PI Supplied Instrument Name: 10 L Niskins 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/ Thermo Delta V Advantage continuous flow gas chromatograph isotope ratio mass spectrometer Thermo Delta V Advantage continuous flow gas chromatograph isotope ratio mass spectrometer PI Supplied Instrument Name: Thermo Delta V Advantage continuous flow gas chromatograph isotope ratio mass spectrometer PI Supplied Instrument Description:a custom-modified Thermo Fisher Scientific Gas Bench II fronted by dual cold traps and a GC Pal autosampler, and analyzed with a Thermo Delta V Advantage continuous flow gas chromatograph isotope ratio mass spectrometer Instrument Name: Thermo Fisher Scientific DELTA V Advantage isotope ratio mass spectrometer Instrument Short Name:Delta V Advantage Instrument Description: The Thermo Scientific DELTA V Advantage is an isotope ratio mass spectrometer designed to measure isotopic, elemental, and molecular ratios of organic and inorganic compounds. The DELTA V Advantage is the standard model of the DELTA V series of isotope ratio mass spectrometers, which can be upgraded to the DELTA V Plus. The DELTA V Advantage can be operated in Continuous Flow or Dual Inlet mode. The standard collector configuration is the Universal Triple Collector. H2 collectors with online hydrogen capability are optional. The DELTA V Advantage is controlled by an automated, integrated Isodat software suite. A magnet, whose pole faces determine the free flight space for the ions, eliminates the traditional flight tube. The magnet is designed for fast mass switching which is further supported by a fast jump control between consecutive measurements of multiple gases within one run. The sample gas is introduced at ground potential, eliminating the need for insulation of the flow path, ensuring 100 percent transfer into the ion source. The amplifiers register ion beams up to 50 V. The DELTA V Advantage has a sensitivity of 1200 molecules per ion (M/I) in Dual Inlet mode and 1500 M/I in Continuous Flow mode. It has a system stability of < 10 ppm and an effective magnetic detection radius of 191 nm. It has a mass range of 1 - 80 Dalton at 3 kV. Thermo Fisher Scientific Gas Bench II Thermo Fisher Scientific Gas Bench II PI Supplied Instrument Name: Thermo Fisher Scientific Gas Bench II PI Supplied Instrument Description:custom-modified Thermo Fisher Scientific Gas Bench II fronted by dual cold traps and a GC Pal autosampler, and analyzed with a Thermo Delta V Advantage continuous flow gas chromatograph isotope ratio mass spectrometer Instrument Name: Thermo-Fisher Scientific Gas Bench II Instrument Short Name:GasBench II Instrument Description: An on-line gas preparation and introduction system for isotope ratio mass spectrometry that is designed for high precision isotope and molecular ratio determination of headspace samples, including water equilibration, carbonates and atmospheric gases. The instrument allows for the use of a dual viscous flow inlet system of repetitive measurements of sample and standard gas on a continuous flow isotope ratio mass spectrometer (CF-IRMS) system. The sample volume is the sample vial (instead of a metal bellows), and the reference gas volume is a pressurized gas tank. The instrument consists of a user programmable autosampler, a gas sampling system, a maintenance-free water removal system, a loop injection system, an isothermal gas chromatograph (GC), an active open split interface, a reference gas injection system with three reference ports, and one or two optional LN2 traps for cryofocusing. The gas sampling system includes a two port needle which adds a gentle flow of He into the sample vial, diluting and displacing sample gas. Water is removed from the sample gas through diffusion traps. The loop injector aliquots the sample gas onto the GC column, which separates the molecular species. The reference gas injection system allows accurate referencing of each sample aliquot to isotopic standards. The system can be used with several options including a carbonate reaction kit that allows injection of anhydrous phospohric acid into sample vials. Note "Finnigan GasBench-II" is the previous brand name of this instrument. Cruise: KM1709 KM1709 R/V Kilo Moana Community Standard Description International Council for the Exploration of the Sea R/V Kilo Moana vessel KM1709 Benedetto Barone University of Hawai'i R/V Kilo Moana Community Standard Description International Council for the Exploration of the Sea R/V Kilo Moana vessel