http://lod.bco-dmo.org/id/dataset/926873 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 2024-05-07 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) Dissolved mercury (Hg) speciation in the California Current System from samples collected on R/V Roger Revelle cruise RR2105 in July to August 2021 2024-05-14 publication 2024-05-14 revision Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA) 2024-05-14 publication https://doi.org/10.26008/1912/bco-dmo.926873.1 Carl Lamborg University of California-Santa Cruz principalInvestigator Amina T. Schartup University of California-San Diego Scripps 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: Adams, H. M., Schartup, A. T., Lamborg, C., Cui, X. (2024) Dissolved mercury (Hg) speciation in the California Current System from samples collected on R/V Roger Revelle cruise RR2105 in July to August 2021. Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2024-05-14 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.926873.1 [access date] Dissolved Mercury Speciation in the California Current System Dataset Description: Methods and Sampling: &lt;p&gt;&lt;strong&gt;Sampling Plan:&lt;/strong&gt;&lt;br /&gt; This study was conducted during the California Current Ecosystem Long Term Ecological Research (CCE LTER) Process Cruise P2105 from July 10 to August 8, 2021, on board the R/V Roger Revelle (RR2105) where we sampled two water parcels and a seven station transect. Water parcels were sampled with a Lagrangian-style process study using drifter floats and modeled after previous CCE LTER cruises (Krause et al., 2015; Landry et al., 2009). During these process studies, an upwelled water parcel was identified by satellite temperature and chlorophyll-a concentrations. We followed an upwelled water parcel for 11 days and a water parcel that had already moved to the eastern edge of the oligotrophic gyre for three days. Profiles for dissolved Hg concentrations, including total mercury (THg), dimethylmercury (DMHg), monomethylmercury (MMHg), and elemental mercury (Hg0), were taken every other day during the water parcel studies. A seven station transect from stations S1-S7 was conducted across the California Current water mass to the coast, and profiles for THg, DMHg, and Hg0 were taken for all stations in the transect. A MMHg profile was only taken for Station S4 in the transect. Stations are colored based on their corresponding water mass in Figure 1 of Adams et al. (2024). Profiles for Hg speciation typically covered the upper water column to 200 meters (m), and those data are presented here. One station within the California Undercurrent was sampled to 600 m, and the concentrations of Hg species in the waters deeper than 200 m are used as a reference for upwelled waters in our mass budget model. Benthic Boundary Layer (BBL) stations were selected based on previous work in the region and are locations where the continental shelf drops off and can have high levels of suspended sediments within the water column (Biller and Bruland, 2013). Samples at BBL stations were taken at one depth around 40 to 70 m identified as 5 m above the sea floor (Biller and Bruland, 2013).&lt;/p&gt; &lt;p&gt;&lt;strong&gt;Sampling Methods:&lt;/strong&gt;&lt;br /&gt; Vertical dissolved Hg profiles were sampled using 5-liter (L) X-Niskin bottles (Ocean Test Equipment) mounted on a trace metal rosette (Seabird) deployed on a non-metallic hydroline (Brzezinski et al., 2015; Cutter and Bruland, 2012) and triggered automatically by pressure on upcasts using a Seabird Auto Fire Module. BBL samples were collected using a 30 L Teflon™-coated GO-Flo™ bottle (General Oceanics) deployed on a non-metallic hydroline and triggered with an acid-cleaned Teflon™ messenger (Bruland et al., 1979). The Niskin or GO-Flo™ bottles were transported into a dedicated Class 100 laboratory van under trace metal-clean conditions (Cutter and Bruland, 2012). Samples were pressure-filtered (N2 gas, 99.99%) directly from the Niskin or GO-Flo™ bottles through 0.2 um capsule filters (Acropak 200, Pall Laboratory) into 2 L acid-cleaned Teflon™ bottles.&lt;/p&gt; &lt;p&gt;An aliquot of sample was transferred from the 2 L Teflon™ bottle into 0.25 L pre-cleaned borosilicate glass bottles (I-Chem) for THg analysis and oxidized with 0.04% bromine monochloride at least 12 hours prior to analysis (U.S. Environmental Protection Agency Method 1631, Revision E).&lt;/p&gt; &lt;p&gt;The remainder of the sample in the 2 L Teflon™ bottle was analyzed for gaseous Hg0 and DMHg with a purge-and-trap method (Bowman et al., 2011; Tseng et al., 2004). Samples were purged with Hg-free N2 gas for 60 minutes ;at a rate of 0.5 L per minute. Effluent gas was passed through a soda lime trap to remove water vapor and aerosols, then DMHg was concentrated onto a Carbotrap® (graphitized carbon black, Sigma-Aldrich) matrix downstream of the soda lime trap, and Hg0 was concentrated onto a gold trap downstream of the Carbotrap® (Tseng et al., 2004; Lamborg et al., 2012). DMHg was thermally desorbed from the Carbotrap® and quantified on board via Gas Chromatographic Cold Vapor Atomic Fluorescence Spectrometry (GC-CVAFS) on a Tekran 2500 (Bowman et al., 2011; Baya et al., 2013). The detection limit for DMHg was 2 fM. Hg0 was quantified by dual gold amalgamation Cold Vapor Atomic Fluorescence Spectroscopy (CVAFS) on a Tekran 2600 following thermal desorption from the gold trap (Tseng et al., 2004; Bloom and Fitzgerald, 1988). The method detection limits for Hg0 were 40 fM (n=14). Sample concentrations for DMHg and Hg0 were determined by a calibration curve based on a gaseous Hg0 standard (Tekran 2505 Mercury Vapor Primary Calibration Unit).&lt;/p&gt; &lt;p&gt;Seawater purged of DMHg and Hg0 was transferred into a 0.25 L precleaned amber borosilicate glass bottles (I-Chem) for MMHg analysis, acidified with 1% sulfuric acid (Trace Metal Grade, Fisher Scientific), stored at 4°C, and analyzed at Scripps Institution of Oceanography within 2 months of collection.&lt;/p&gt; &lt;p&gt;THg samples were analyzed following U.S. EPA Method 1631 on board the ship (U.S. Environmental Protection Agency Method 1631, Revision E; Lamborg et al., 2012). Samples were reduced to Hg0 with 20% wt:vol tin (II) chloride solution (ACS grade, Fisher Chemical) in 10% hydrochloric acid (ACS grade, Fisher Chemical). Hg0 was purged onto a gold trap with Hg-free argon gas and thermally desorbed via CVAFS for detection using a Tekran 2600 Automated Mercury Analyzer. Sample concentrations were determined by a calibration curve based on a gaseous Hg0 standard (Tekran 2505 Mercury Vapor Primary Calibration Unit). The method detection limit was 0.22 pM (n=8 blanks) and replicates had an average precision of 6.4% (n = 73).&lt;/p&gt; &lt;p&gt;MMHg samples were analyzed by ascorbic acid-assisted direct ethylation following Munson et al. (2014) and U.S. EPA Method 1630 (U.S. Environmental Protection Agency Method 1630; Munson et al., 2014). Samples were adjusted to a pH of 4.8 using a 2 M acetate/glacial acetic acid buffer (J.T. Baker) in ultrapure water (Milli-Q, 18.2 MW per centimeter) and 8 M potassium hydroxide (J.T. Baker) in ultrapure water (Milli-Q, 18.2 MW per centimeter). 2.5% wt:vol ascorbic acid (J.T. Baker) in ultrapure water (Milli-Q, 18.2 MW per centimeter was added to the samples, then samples were ethylated with sodium tetraethylborate (NaTEB) solution (1% NaTEB in 2% potassium hydroxide, Strem Chemicals) to convert MMHg to volatile methylethylmercury. Ethylation was allowed to proceed for 10 minutes before sample analysis. Samples were analyzed by GC-CVAFS on a Tekran 2700 Automated Methylmercury Analyzer. Concentrations were determined by a calibration curve based on standards prepared from a certified 1000 ppm MMHg (II) chloride standard (Alfa Aesar). The method detection limit was 11.3 fM (n=9 blanks), and ongoing precision and recovery was 98.4 ± 7.9% (n=25). Replicates had an average precision of 9.2% (n=18) and matrix spike recovery was 112 ± 13% (n=15).&lt;/p&gt; Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-1637632 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=1637632 Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-2023031 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=2023031 Funding provided by NSF Division of Ocean Sciences (NSF OCE) Award Number: OCE-2023046 Award URL: https://www.nsf.gov/awardsearch/show-award?AWD_ID=2023046 completed Carl Lamborg University of California-Santa Cruz 831-459-2908 A442 Earth & Marine Sciences 1156 High Street Santa Cruz CA 95064 USA clamborg@ucsc.edu pointOfContact Amina T. Schartup University of California-San Diego Scripps 858-534-8752 UC San Diego 9500 Gilman Dr #0220 La Jolla CA 92093-0220 USA aschartup@ucsd.edu pointOfContact asNeeded Dataset Version: 1 Unknown Water_Mass Station_Name ISO_DateTime_PDT ISO_DateTime_UTC Latitude Longitude Trace_Metal_Cast_Num Depth_m Temperature_C Salinity_PSU Oxygen_umol_kg Density_kg_m3 DMHg_fM DMHg_Flag Hg0_fM Hg0_Flag MMHg_fM MMHg_Flag THg_pM THg_Flag 30 L Teflon™-coated GO-Flo™ bottle (General Oceanics) 5 L X-Niskin bottles (Ocean Test Equipment) Seabird Scientific SBE-43 Seabird Scientific SBE-45 Gas Chromatographic Cold Vapor Atomic Fluorescence Spectrometry (GC-CVAFS) on a Tekran 2500 Cold Vapor Atomic Fluorescence Spectroscopy (CVAFS) on a Tekran 2600 Automated Mercury Analyzer GC-CVAFS on a Tekran 2700 Automated Methylmercury Analyzer theme None, User defined region station ISO_DateTime_Local ISO_DateTime_UTC latitude longitude cast depth water temperature at measurement depth salinity dissolved Oxygen density DMHg Elemental Mercury MMHg total mercury featureType BCO-DMO Standard Parameters GO-FLO Bottle Niskin bottle Sea-Bird SBE 43 Dissolved Oxygen Sensor Sea-Bird SBE 45 MicroTSG Thermosalinograph Tekran 2500 CVAFS mercury detector Tekran 2600 Automated Total Mercury Analyzer series Tekran Model 2700 Automated Methyl Mercury Analysis System instrument BCO-DMO Standard Instruments RR2105 service Deployment Activity California Current System, Northeastern Pacific Ocean 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. Ocean Carbon and Biogeochemistry http://us-ocb.org/ Ocean Carbon and Biogeochemistry The Ocean Carbon and Biogeochemistry (OCB) program focuses on the ocean's role as a component of the global Earth system, bringing together research in geochemistry, ocean physics, and ecology that inform on and advance our understanding of ocean biogeochemistry. The overall program goals are to promote, plan, and coordinate collaborative, multidisciplinary research opportunities within the U.S. research community and with international partners. Important OCB-related activities currently include: the Ocean Carbon and Climate Change (OCCC) and the North American Carbon Program (NACP); U.S. contributions to IMBER, SOLAS, CARBOOCEAN; and numerous U.S. single-investigator and medium-size research projects funded by U.S. federal agencies including NASA, NOAA, and NSF. The scientific mission of OCB is to study the evolving role of the ocean in the global carbon cycle, in the face of environmental variability and change through studies of marine biogeochemical cycles and associated ecosystems. The overarching OCB science themes include improved understanding and prediction of: 1) oceanic uptake and release of atmospheric CO2 and other greenhouse gases and 2) environmental sensitivities of biogeochemical cycles, marine ecosystems, and interactions between the two. The OCB Research Priorities (updated January 2012) include: ocean acidification; terrestrial/coastal carbon fluxes and exchanges; climate sensitivities of and change in ecosystem structure and associated impacts on biogeochemical cycles; mesopelagic ecological and biogeochemical interactions; benthic-pelagic feedbacks on biogeochemical cycles; ocean carbon uptake and storage; and expanding low-oxygen conditions in the coastal and open oceans. OCB largerWorkCitation program Long Term Ecological Research network http://www.lternet.edu/ Long Term Ecological Research network adapted from http://www.lternet.edu/ The National Science Foundation established the LTER program in 1980 to support research on long-term ecological phenomena in the United States. The Long Term Ecological Research (LTER) Network is a collaborative effort involving more than 1800 scientists and students investigating ecological processes over long temporal and broad spatial scales. The LTER Network promotes synthesis and comparative research across sites and ecosystems and among other related national and international research programs. The LTER research sites represent diverse ecosystems with emphasis on different research themes, and cross-site communication, network publications, and research-planning activities are coordinated through the LTER Network Office. 2017 LTER research site map obtained from https://lternet.edu/site/lter-network/ LTER largerWorkCitation program California Current Ecosystem Long Term Ecological Research site http://cce.lternet.edu/ California Current Ecosystem Long Term Ecological Research site <p><strong>From ccelter.edu:</strong><br /> The California Current System is a coastal upwelling biome, as found along the eastern margins of all major ocean basins. These are among the most productive ecosystems in the world ocean. The California Current Ecosystem LTER (32.9 degrees North, 120.3 degrees West) is investigating nonlinear transitions in the California Current coastal pelagic ecosystem, with particular attention to long-term forcing by a secular warming trend, the Pacific Decadal Oscillation, and El Nino in altering the structure and dynamics of the pelagic ecosystem. The California Current sustains active fisheries for a variety of finfish and marine invertebrates, modulates weather patterns and the hydrologic cycle of much of the western United States, and plays a vital role in the economy of myriad coastal communities.</p> <p><strong>LTER Data:</strong><br /> The California Current Ecosystem (CCE) LTER data are managed by and available directly from the CCE project data site URL shown above. If there are any datasets listed below, they are data sets that were collected at or near the CCE LTER sampling locations, and funded by NSF OCE as ancillary projects related to the CCE LTER core research themes.</p> <p><strong>NSF Award Abstract (OCE-2224726)<strong>:</strong></strong><br /> Coastal upwelling regions are found along the eastern boundaries of all ocean basins and are some of the most productive ecosystems in the ocean. This award is supporting the California Current Ecosystem Long Term Ecological Research (CCE LTER) site in a major upwelling biome. It leverages the 73-year California Cooperative Oceanic Fisheries Investigations (CalCOFI) program which provides essential information characterizing climate variability and change in this system. The CCE LTER addresses two over-arching questions: What are the mechanisms leading to ecological transitions in a coastal pelagic ecosystem? And what is the interplay between changing ocean climate, community structure, and ecosystem dynamics? The investigators are working towards diagnosing mechanisms of ecosystem change and developing a quantitative framework for forecasting future conditions and how these might affect the management of key living marine resources, including numerous fishes, invertebrates, marine mammals, and seabirds. They are training graduate and undergraduate students, as well as providing educational opportunities for teachers. Public programs and outreach efforts in collaboration with the Birch Aquarium at Scripps Institution of Oceanography are increasing public awareness and understanding of climate effects on coastal pelagic communities and connecting the public to cutting-edge ocean research.</p> <p>This project is adding to understanding of the mechanisms underlying abrupt ecological transitions with three interrelated foci: (1) investigation of marine heatwaves and resultant multiple stressors on organisms and communities, (2) elucidation of ecological stoichiometry and the response of multiple trophic levels to altered elemental ratios of source nutrients, and (3) analysis of top-down pressures mediated by a diverse suite of organisms. It is sustaining multi-scale measurements of five core LTER variables and responses to ocean warming, increased stratification, acidification, deoxygenation, and altered nutrient stoichiometry in the Northeast Pacific. The investigators are using long-term, spatially-resolved time series at multiple spatial scales to evaluate community shifts at multiple temporal scales, with new measurements allowing interrogation at finer taxonomic levels. They are conducting in situ multi-factorial experiments (temperature, macronutrients, micronutrients, light, grazing) in combination with genomic and transcriptomic analyses. These will complement time series measurements, inform next-generation biogeochemical models, and test hypotheses related to ecological stoichiometry and marine heatwaves. The team is also using a suite of imaging techniques, molecular and morphological methods, and active and passive acoustic approaches to quantify vertical structure and cooccurrence of organisms across trophic levels and test hypotheses about top-down control of the ecosystem.</p> <p>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.</p> <p><strong>This project is supported by continuing grants with name variations:</strong></p> <ul> <li>LTER: Nonlinear transitions in the California Current Coastal Pelagic Ecosystem</li> <li>Ecological Transitions in the California Current Ecosystem: CCE-LTER Phase II</li> <li>LTER: CCE-LTER Phase III: Ecological Transitions in an Eastern Boundary Current Upwelling Ecosystem</li> <li>LTER: Ecosystem controls and multiple stressors in a coastal upwelling system - CCE IV</li> </ul> CCE LTER largerWorkCitation project Collaborative Proposal: Unravelling the Oceanic Dimethylmercury Cycle https://osprey.bco-dmo.org/project/908151 Collaborative Proposal: Unravelling the Oceanic Dimethylmercury Cycle <p><em>NSF Award Abstract:</em><br /> This project will study how dimethylmercury is formed and removed in the oceans. Dimethylmercury is a naturally occurring compound. It is thought to be formed when man-made mercury is converted into monomethylmercury, a toxin that accumulates in fish. Despite representing a large fraction of mercury in the oceans, the origin and fate of dimethylmercury is not known. This research will use state-of-the-art analytical, genomic and modeling tools to address this information gap. It will also train graduate and undergraduate students to use field, experimental, and modeling methods. The results will be used in predictive models to forecast future trends in the oceanic mercury cycle. These models are needed to evaluate the effectiveness of international actions that seek to reverse increasing trends in the bioaccumulation of monomethylmercury in fish.</p> <p>Methylated mercury species in the ocean are formed in sediment and the water column from inorganic divalent mercury delivered from the atmosphere and rivers. The putative mechanism is a two-step process during which monomethylmercury is formed first, followed by slow methylation into dimethylmercury. The first step, biomethylation of divalent mercury into monomethylmercury, is relatively well-studied in sediment and known to be driven by sulfate- and iron-reducing bacteria and methanogens. The mechanism for monomethylmercury formation in the water column is less well understood, and the process of dimethylmercury formation in sediment or seawater is essentially unknown. Until recently, it was assumed that dimethylmercury represented a small enough fraction of the methylated and total mercury (the sum of all mercury species) pools to be insignificant in the global mercury cycle. Recent measurements, however, show that dimethylmercury levels in seawater can be in the same range as the other mercury species. This project will identify the biological and chemical methylating agents involved in the formation of dimethylmercury. Further, it will test the impact of varying biogeochemical conditions on dimethylmercury production. Results will be used to update the mercury module of the MIT General Circulation Model (MITgcm, a global biogeochemical model, and analyze the impacts of dimethylmercury production and degradation on monomethylmercury concentrations.</p> <p>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.</p> DMHg in the Ocean largerWorkCitation project eng; USA oceans California Current System, Northeastern Pacific Ocean -130.54799 -120.406468 34.423331 36.561859 2021-07-19 2021-08-09 From projects that focused on the following 2 locations: 1. California coastal current 2. Monterey Bay, California Current, Greenland 0 BCO-DMO catalogue of parameters from Dissolved mercury (Hg) speciation in the California Current System from samples collected on R/V Roger Revelle cruise RR2105 in July to August 2021 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/927328.rdf Name: Water_Mass Units: unitless Description: <p>Identification of water mass</p> http://lod.bco-dmo.org/id/dataset-parameter/927329.rdf Name: Station_Name Units: unitless Description: <p>Name of the station</p> http://lod.bco-dmo.org/id/dataset-parameter/927330.rdf Name: ISO_DateTime_PDT Units: unitless Description: <p>Sampling date and time in ISO 8601 format in Pacific Daylight Time (PDT) time zone</p> http://lod.bco-dmo.org/id/dataset-parameter/927331.rdf Name: ISO_DateTime_UTC Units: unitless Description: <p>Sampling date and time in ISO 8601 format in UTC time zone</p> http://lod.bco-dmo.org/id/dataset-parameter/927332.rdf Name: Latitude Units: decimal degrees Description: <p>Station latitude, south is negative</p> http://lod.bco-dmo.org/id/dataset-parameter/927333.rdf Name: Longitude Units: decimal degrees Description: <p>Station longitude, west is negative</p> http://lod.bco-dmo.org/id/dataset-parameter/927334.rdf Name: Trace_Metal_Cast_Num Units: unitless Description: <p>Cast number</p> http://lod.bco-dmo.org/id/dataset-parameter/927335.rdf Name: Depth_m Units: meters (m) Description: <p>Sample depth</p> http://lod.bco-dmo.org/id/dataset-parameter/927336.rdf Name: Temperature_C Units: degrees Celsius Description: <p>Sample temperature</p> http://lod.bco-dmo.org/id/dataset-parameter/927337.rdf Name: Salinity_PSU Units: practical salinity units (PSU) Description: <p>Sample salinity</p> http://lod.bco-dmo.org/id/dataset-parameter/927338.rdf Name: Oxygen_umol_kg Units: micromole per kilogram (umol/kg) Description: <p>Dissolved oxygen concentration</p> http://lod.bco-dmo.org/id/dataset-parameter/927339.rdf Name: Density_kg_m3 Units: kilogram per cubed meter (kg/m^3) Description: <p>Water density</p> http://lod.bco-dmo.org/id/dataset-parameter/927340.rdf Name: DMHg_fM Units: femtomolar (fM) Description: <p>Concentration of dimethylmercury; limit of detection = 2</p> http://lod.bco-dmo.org/id/dataset-parameter/927341.rdf Name: DMHg_Flag Units: unitless Description: <p>Data flag, 0 indicates that the data was used in analyses, 1 indicates that the data was removed from subsequent analysis as it was 1.5*IQR above the upper whisker when the data was plotted as a box plot</p> http://lod.bco-dmo.org/id/dataset-parameter/927342.rdf Name: Hg0_fM Units: femtomolar (fM) Description: <p>Concentration of elemental mercury; limit of detection = 40</p> http://lod.bco-dmo.org/id/dataset-parameter/927343.rdf Name: Hg0_Flag Units: unitless Description: <p>Data flag, 0 indicates that the data was used in analyses, 1 indicates that the data was removed from subsequent analysis as it was 1.5*IQR above the upper whisker when the data was plotted as a box plot</p> http://lod.bco-dmo.org/id/dataset-parameter/927344.rdf Name: MMHg_fM Units: femtomolar (fM) Description: <p>Concentration of dissolved monomethylmercury; limit of detection = 11.3</p> http://lod.bco-dmo.org/id/dataset-parameter/927345.rdf Name: MMHg_Flag Units: unitless Description: <p>Data flag, 0 indicates that the data was used in analyses, 1 indicates that the data was removed from subsequent analysis as it was 1.5*IQR above the upper whisker when the data was plotted as a box plot</p> http://lod.bco-dmo.org/id/dataset-parameter/927346.rdf Name: THg_pM Units: picomolar (pM) Description: <p>Concentration of dissolved total mercury; limit of detection = 0.22</p> http://lod.bco-dmo.org/id/dataset-parameter/927347.rdf Name: THg_Flag Units: unitless Description: <p>Data flag, 0 indicates that the data was used in analyses, 1 indicates that the data was removed from subsequent analysis as it was 1.5*IQR above the upper whisker when the data was plotted as a box plot</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 24565 https://darchive.mblwhoilibrary.org/server/api/core/bitstreams/98b9c0c3-0de8-494c-a9ef-b816cc89c6e3/content download https://doi.org/10.26008/1912/bco-dmo.926873.1 download onLine dataset &lt;p&gt;&lt;strong&gt;Sampling Plan:&lt;/strong&gt;&lt;br /&gt; This study was conducted during the California Current Ecosystem Long Term Ecological Research (CCE LTER) Process Cruise P2105 from July 10 to August 8, 2021, on board the R/V Roger Revelle (RR2105) where we sampled two water parcels and a seven station transect. Water parcels were sampled with a Lagrangian-style process study using drifter floats and modeled after previous CCE LTER cruises (Krause et al., 2015; Landry et al., 2009). During these process studies, an upwelled water parcel was identified by satellite temperature and chlorophyll-a concentrations. We followed an upwelled water parcel for 11 days and a water parcel that had already moved to the eastern edge of the oligotrophic gyre for three days. Profiles for dissolved Hg concentrations, including total mercury (THg), dimethylmercury (DMHg), monomethylmercury (MMHg), and elemental mercury (Hg0), were taken every other day during the water parcel studies. A seven station transect from stations S1-S7 was conducted across the California Current water mass to the coast, and profiles for THg, DMHg, and Hg0 were taken for all stations in the transect. A MMHg profile was only taken for Station S4 in the transect. Stations are colored based on their corresponding water mass in Figure 1 of Adams et al. (2024). Profiles for Hg speciation typically covered the upper water column to 200 meters (m), and those data are presented here. One station within the California Undercurrent was sampled to 600 m, and the concentrations of Hg species in the waters deeper than 200 m are used as a reference for upwelled waters in our mass budget model. Benthic Boundary Layer (BBL) stations were selected based on previous work in the region and are locations where the continental shelf drops off and can have high levels of suspended sediments within the water column (Biller and Bruland, 2013). Samples at BBL stations were taken at one depth around 40 to 70 m identified as 5 m above the sea floor (Biller and Bruland, 2013).&lt;/p&gt; &lt;p&gt;&lt;strong&gt;Sampling Methods:&lt;/strong&gt;&lt;br /&gt; Vertical dissolved Hg profiles were sampled using 5-liter (L) X-Niskin bottles (Ocean Test Equipment) mounted on a trace metal rosette (Seabird) deployed on a non-metallic hydroline (Brzezinski et al., 2015; Cutter and Bruland, 2012) and triggered automatically by pressure on upcasts using a Seabird Auto Fire Module. BBL samples were collected using a 30 L Teflon™-coated GO-Flo™ bottle (General Oceanics) deployed on a non-metallic hydroline and triggered with an acid-cleaned Teflon™ messenger (Bruland et al., 1979). The Niskin or GO-Flo™ bottles were transported into a dedicated Class 100 laboratory van under trace metal-clean conditions (Cutter and Bruland, 2012). Samples were pressure-filtered (N2 gas, 99.99%) directly from the Niskin or GO-Flo™ bottles through 0.2 um capsule filters (Acropak 200, Pall Laboratory) into 2 L acid-cleaned Teflon™ bottles.&lt;/p&gt; &lt;p&gt;An aliquot of sample was transferred from the 2 L Teflon™ bottle into 0.25 L pre-cleaned borosilicate glass bottles (I-Chem) for THg analysis and oxidized with 0.04% bromine monochloride at least 12 hours prior to analysis (U.S. Environmental Protection Agency Method 1631, Revision E).&lt;/p&gt; &lt;p&gt;The remainder of the sample in the 2 L Teflon™ bottle was analyzed for gaseous Hg0 and DMHg with a purge-and-trap method (Bowman et al., 2011; Tseng et al., 2004). Samples were purged with Hg-free N2 gas for 60 minutes ;at a rate of 0.5 L per minute. Effluent gas was passed through a soda lime trap to remove water vapor and aerosols, then DMHg was concentrated onto a Carbotrap® (graphitized carbon black, Sigma-Aldrich) matrix downstream of the soda lime trap, and Hg0 was concentrated onto a gold trap downstream of the Carbotrap® (Tseng et al., 2004; Lamborg et al., 2012). DMHg was thermally desorbed from the Carbotrap® and quantified on board via Gas Chromatographic Cold Vapor Atomic Fluorescence Spectrometry (GC-CVAFS) on a Tekran 2500 (Bowman et al., 2011; Baya et al., 2013). The detection limit for DMHg was 2 fM. Hg0 was quantified by dual gold amalgamation Cold Vapor Atomic Fluorescence Spectroscopy (CVAFS) on a Tekran 2600 following thermal desorption from the gold trap (Tseng et al., 2004; Bloom and Fitzgerald, 1988). The method detection limits for Hg0 were 40 fM (n=14). Sample concentrations for DMHg and Hg0 were determined by a calibration curve based on a gaseous Hg0 standard (Tekran 2505 Mercury Vapor Primary Calibration Unit).&lt;/p&gt; &lt;p&gt;Seawater purged of DMHg and Hg0 was transferred into a 0.25 L precleaned amber borosilicate glass bottles (I-Chem) for MMHg analysis, acidified with 1% sulfuric acid (Trace Metal Grade, Fisher Scientific), stored at 4°C, and analyzed at Scripps Institution of Oceanography within 2 months of collection.&lt;/p&gt; &lt;p&gt;THg samples were analyzed following U.S. EPA Method 1631 on board the ship (U.S. Environmental Protection Agency Method 1631, Revision E; Lamborg et al., 2012). Samples were reduced to Hg0 with 20% wt:vol tin (II) chloride solution (ACS grade, Fisher Chemical) in 10% hydrochloric acid (ACS grade, Fisher Chemical). Hg0 was purged onto a gold trap with Hg-free argon gas and thermally desorbed via CVAFS for detection using a Tekran 2600 Automated Mercury Analyzer. Sample concentrations were determined by a calibration curve based on a gaseous Hg0 standard (Tekran 2505 Mercury Vapor Primary Calibration Unit). The method detection limit was 0.22 pM (n=8 blanks) and replicates had an average precision of 6.4% (n = 73).&lt;/p&gt; &lt;p&gt;MMHg samples were analyzed by ascorbic acid-assisted direct ethylation following Munson et al. (2014) and U.S. EPA Method 1630 (U.S. Environmental Protection Agency Method 1630; Munson et al., 2014). Samples were adjusted to a pH of 4.8 using a 2 M acetate/glacial acetic acid buffer (J.T. Baker) in ultrapure water (Milli-Q, 18.2 MW per centimeter) and 8 M potassium hydroxide (J.T. Baker) in ultrapure water (Milli-Q, 18.2 MW per centimeter). 2.5% wt:vol ascorbic acid (J.T. Baker) in ultrapure water (Milli-Q, 18.2 MW per centimeter was added to the samples, then samples were ethylated with sodium tetraethylborate (NaTEB) solution (1% NaTEB in 2% potassium hydroxide, Strem Chemicals) to convert MMHg to volatile methylethylmercury. Ethylation was allowed to proceed for 10 minutes before sample analysis. Samples were analyzed by GC-CVAFS on a Tekran 2700 Automated Methylmercury Analyzer. Concentrations were determined by a calibration curve based on standards prepared from a certified 1000 ppm MMHg (II) chloride standard (Alfa Aesar). The method detection limit was 11.3 fM (n=9 blanks), and ongoing precision and recovery was 98.4 ± 7.9% (n=25). Replicates had an average precision of 9.2% (n=18) and matrix spike recovery was 112 ± 13% (n=15).&lt;/p&gt; Specified by the Principal Investigator(s) - Imported original file &quot;2024-0311-California Current System Dissolved Hg Speciation.xlsx&quot; into the BCO-DMO system. - Marked &quot;N/A&quot; as a missing data value (missing data are empty/blank in the final CSV file). - Made corrections in the time column: added &quot;AM&quot; where needed to the times missing them and converted the times that were in 24-hour time to 12-hour AM/PM time. - Converted the date and time columns into ISO 8601 format in PDT and UTC time zones. - Renamed fields to comply with BCO-DMO naming conventions. - Saved final file as &quot;926873_v1_dissolved_hg_speciation_california_current_system.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 30 L Teflon™-coated GO-Flo™ bottle (General Oceanics) 30 L Teflon™-coated GO-Flo™ bottle (General Oceanics) PI Supplied Instrument Name: 30 L Teflon™-coated GO-Flo™ bottle (General Oceanics) PI Supplied Instrument Description:Used for dissolved mercury samples collected at Benthic Boundary Layer Stations. Instrument Name: GO-FLO Bottle Instrument Short Name:GO-FLO Instrument Description: GO-FLO bottle cast used to collect water samples for pigment, nutrient, plankton, etc. The GO-FLO sampling bottle is specially designed to avoid sample contamination at the surface, internal spring contamination, loss of sample on deck (internal seals), and exchange of water from different depths. Community Standard Description: http://vocab.nerc.ac.uk/collection/L05/current/30/ 5 L X-Niskin bottles (Ocean Test Equipment) 5 L X-Niskin bottles (Ocean Test Equipment) PI Supplied Instrument Name: 5 L X-Niskin bottles (Ocean Test Equipment) PI Supplied Instrument Description:Dissolved mercury samples were collected using a trace metal clean rosette equipped with 5-liter X-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/ Seabird Scientific SBE-43 Seabird Scientific SBE-43 PI Supplied Instrument Name: Seabird Scientific SBE-43 PI Supplied Instrument Description:Depth, temperature, salinity, and oxygen concentrations were determined from real-time hydrographic data from the ship's rosette using Seabird Scientific SBE11, SBE-43, and SBE-45 devices. Instrument Name: Sea-Bird SBE 43 Dissolved Oxygen Sensor Instrument Short Name:SBE-43 DO Instrument Description: The Sea-Bird SBE 43 dissolved oxygen sensor is a redesign of the Clark polarographic membrane type of dissolved oxygen sensors. more information from Sea-Bird Electronics Community Standard Description: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0036/ Seabird Scientific SBE-45 Seabird Scientific SBE-45 PI Supplied Instrument Name: Seabird Scientific SBE-45 PI Supplied Instrument Description:Depth, temperature, salinity, and oxygen concentrations were determined from real-time hydrographic data from the ship's rosette using Seabird Scientific SBE11, SBE-43, and SBE-45 devices. Instrument Name: Sea-Bird SBE 45 MicroTSG Thermosalinograph Instrument Short Name:SBE 45 MicroTSG Instrument Description: A small externally powered, high-accuracy instrument, designed for shipboard determination of sea surface (pumped-water) conductivity and temperature. It is constructed of plastic and titanium to ensure long life with minimum maintenance. It may optionally be interfaced to an external SBE 38 hull temperature sensor. Sea Bird SBE 45 MicroTSG (Thermosalinograph) Community Standard Description: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0190/ Gas Chromatographic Cold Vapor Atomic Fluorescence Spectrometry (GC-CVAFS) on a Tekran 2500 Gas Chromatographic Cold Vapor Atomic Fluorescence Spectrometry (GC-CVAFS) on a Tekran 2500 PI Supplied Instrument Name: Gas Chromatographic Cold Vapor Atomic Fluorescence Spectrometry (GC-CVAFS) on a Tekran 2500 PI Supplied Instrument Description:Dissolved dimethylmercury concentrations were measured using a Tekran 2500. Instrument Name: Tekran 2500 CVAFS mercury detector Instrument Short Name: Instrument Description: Tekran 2500 Total Mercury Analysis System (not automated; cold vapor atomic fluorescence spectrometry) Cold Vapor Atomic Fluorescence Spectroscopy (CVAFS) on a Tekran 2600 Automated Mercury Analyzer Cold Vapor Atomic Fluorescence Spectroscopy (CVAFS) on a Tekran 2600 Automated Mercury Analyzer PI Supplied Instrument Name: Cold Vapor Atomic Fluorescence Spectroscopy (CVAFS) on a Tekran 2600 Automated Mercury Analyzer PI Supplied Instrument Description:Dissolved Total Mercury and elemental mercury were analyzed on a Tekran 2600. Instrument Name: Tekran 2600 Automated Total Mercury Analyzer series Instrument Short Name:Tekran 2600 Instrument Description: The Tekran 2600 is a total Mercury (Hg) analysis system that can measure sub-picogram quantities of mercury in water, soil, vegetation, and other sample matrices. The system utilizes a Cold Vapour Atomic Fluorescence Spectroscopy (CVAFS) detector. The 2600-IVS (In-Vial Sparging) model is reconfigured for direct in-vial sparging sample introduction, and the 2600-NG (Natural Gas) model is designed for the analysis of gas phase sample cartridges. The system is capable of multiple method configurations: Dual stage gold preconcentration (EPA Method 1631); Direct measurement without preconcentration (EPA Method 245.7); Air sample analysis on gold traps (EPA Compendium Method IO-5); and Natural gas analysis on gold traps (ASTM D-6350, ISO 6978). It has a guaranteed minimum detection limit of < 0.05 nanograms per liter (ng/L). In clean room environments, with low mercury blanks, minimum detection limits as low as 0.02 ng/L are achievable. See: https://www.tekran.com/products/laboratory/tekran-model-2600-automated-total-mercury-analysis-system/ GC-CVAFS on a Tekran 2700 Automated Methylmercury Analyzer GC-CVAFS on a Tekran 2700 Automated Methylmercury Analyzer PI Supplied Instrument Name: GC-CVAFS on a Tekran 2700 Automated Methylmercury Analyzer PI Supplied Instrument Description:Dissolved monomethylmercury was measured on a Tekran 2700. Instrument Name: Tekran Model 2700 Automated Methyl Mercury Analysis System Instrument Short Name:Tekran 2700 Instrument Description: The Tekran 2700 is a fully integrated Gas Chromatography Cold-Vapor Atomic Fluorescence Spectrophotometer (GC-CVAFS) automated Methyl Mercury analysis system. The 2700 can analyze distilled waters, extracted or distilled tissues and solids, and allows direct analysis of suitable water samples. The system is pre-programmed to run EPA Method 1630, however it offers complete method customization including: GC column temperature ramping; programmable analysis cycle settings; high temperature purge cycles; and choice of trap and GC column. It can also interface with ICP-MS or other analytical instruments. The sample analysis cycle is less than 7 minutes per sample. It has a minimum detection limit of 0.002 nanograms per liter (ng/L). The system has IR trap heating and active cooling. See: https://www.tekran.com/products/laboratory/tekran-model-2700-automated-methyl-mercury-analysis-system/ Cruise: RR2105 RR2105 R/V Roger Revelle Community Standard Description International Council for the Exploration of the Sea R/V Roger Revelle vessel RR2105 Michael R. Stukel Florida State University R/V Roger Revelle Community Standard Description International Council for the Exploration of the Sea R/V Roger Revelle vessel