1b:I[42426,["/_next/static/immutable/chunks/1xctgzqre-wsy.js","/_next/static/immutable/chunks/06_-wz6pdtp2b.js","/_next/static/immutable/chunks/30e52g49hg40p.js","/_next/static/immutable/chunks/02yq6tul2z-oh.js","/_next/static/immutable/chunks/10bx_ec2vj7n_.js","/_next/static/immutable/chunks/33bfn03fo8xnt.js","/_next/static/immutable/chunks/0tfjf78scu61b.js","/_next/static/immutable/chunks/31xnvej4n1bi9.js"],"default"] 1c:T12bf,Much of this text appeared in an article published in OCB News, October 2008, by the OCB Project Office. The first U.S. GEOTRACES Atlantic Section will be specifically centered around a sampling cruise to be carried out in the North Atlantic in 2010. Ed Boyle (MIT) and Bill Jenkins (WHOI) organized a three-day planning workshop that was held September 22-24, 2008 at the Woods Hole Oceanographic Institution. The main goal of the workshop, sponsored by the National Science Foundation and the U.S. GEOTRACES Scientific Steering Committee, was to design the implementation plan for the first U.S. GEOTRACES Atlantic Section. The primary cruise design motivation was to improve knowledge of the sources, sinks and internal cycling of Trace Elements and their Isotopes (TEIs) by studying their distributions along a section in the North Atlantic (Figure 1). The North Atlantic has the full suite of processes that affect TEIs, including strong meridional advection, boundary scavenging and source effects, aeolian deposition, and the salty Mediterranean Outflow. The North Atlantic is particularly important as it lies at the "origin" of the global Meridional Overturning Circulation. It is well understood that many trace metals play important roles in biogeochemical processes and the carbon cycle, yet very little is known about their large-scale distributions and the regional scale processes that affect them. Recent advances in sampling and analytical techniques, along with advances in our understanding of their roles in enzymatic and catalytic processes in the open ocean provide a natural opportunity to make substantial advances in our understanding of these important elements. Moreover, we are motivated by the prospect of global change and the need to understand the present and future workings of the ocean's biogeochemistry. The GEOTRACES strategy is to measure a broad suite of TEIs to constrain the critical biogeochemical processes that influence their distributions. In addition to these "exotic" substances, more traditional properties, including macronutrients (at micromolar and nanomolar levels), CTD, bio-optical parameters, and carbon system characteristics will be measured. The cruise starts at Line W, a repeat hydrographic section southeast of Cape Cod, extends to Bermuda and subsequently through the North Atlantic oligotrophic subtropical gyre, then transects into the African coast in the northern limb of the coastal upwelling region. From there, the cruise goes northward into the Mediterranean outflow. The station locations shown on the map are for the "fulldepth TEI" stations, and constitute approximately half of the stations to be ultimately occupied. Figure 1. The proposed 2010 Atlantic GEOTRACES cruise track plotted on dissolved oxygen at 400 m depth. Data from the World Ocean Atlas (Levitus et al., 2005) were plotted using Ocean Data View (courtesy Reiner Schlitzer). [click on the image to view a larger version] Hydrography, CTD and nutrient measurements will be supported by the Ocean Data Facility (J. Swift) at Scripps Institution of Oceanography and funded through NSF Facilities. They will be providing an additional CTD rosette system along with nephelometer and LADCP. A trace metal clean Go-Flo Rosette and winch will be provided by the group at Old Dominion University (G. Cutter) along with a towed underway pumping system. The North Atlantic Transect cruise began in 2010 with KN199 leg 4 (station sampling) and leg 5 (underway sampling only) (Figure 2). KN199-04 Cruise Report (PDF) Figure 2. The red line shows the cruise track for the first leg of the US Geotraces North Atlantic Transect on the R/V Knorr in October 2010. The rest of the stations (beginning with 13) will be completed in October-December 2011 on the R/V Knorr (courtesy of Bill Jenkins, Chief Scientist, GNAT first leg). [click on the image to view a larger version] The section completion effort resumed again in November 2011 with KN204-01A,B (Figure 3). KN204-01A,B Cruise Report (PDF) Figure 3. Station locations occupied on the US Geotraces North Atlantic Transect on the R/V Knorr in November 2011. [click on the image to view a larger version] Data from the North Atlantic Transect cruises are available under the Datasets heading below, and consensus values for the SAFe and North Atlantic GEOTRACES Reference Seawater Samples are available from the GEOTRACES Program Office: Standards and Reference Materials ADCP data are available from the Currents ADCP group at the University of Hawaii at the links below: KN199-04 (leg 1 of 2010 cruise; Lisbon to Cape Verde) KN199-05 (leg 2 of 2010 cruise; Cape Verde to Charleston, NC) KN204-01A (part 1 of 2011 cruise; Woods Hole, MA to Bermuda) KN204-01B (part 2 of 2011 cruise; Bermuda to Cape Verde)6:["$","$L1b",null,{"dataset":{"_id":"3830","description":"

Surface transects for arsenic speciation, antimony speciation, and alkaline phosphatase activity

Data for the concentrations of the dissolved (<0.4 µm) arsenic species: total inorganic As (III+V), arsenite (AsIII), As(V), monomethyl As, dimethyl As, and the activity of the enzyme alkaline phosphatase (unfiltered).

Please note that some US GEOTRACES data may not be final, pending intercalibration results and further analysis. If you are interested in following changes to US GEOTRACES NAT data, there is an RSS feed available via the BCO-DMO US GEOTRACES project page (http://www.bco-dmo.org/project/2066; scroll down and expand the \"Datasets\" section).

\n","problem":"","acquisition":"

Filtered (0.4 micromole) water samples from the Geotraces surface tow-fish taken at discrete times were placed into 500 mL Teflon FEP bottles, refrigerated, and analyzed within 24 hours of collection. Arsenic and antimony speciation determined using selective hydride generation, liquid nitrogen-cooled trapping, and then revolatilization and determination with gas chromatography/photoionization detection (Cutter et al., 1991; Cutter and Cutter, 2006).

Calibration performed daily via the standard additions method, with a minimum of 4 additions of AsIII, AsV, MMAs, or DMAs depending on the analyses. The slope from the linear fit to these data was then applied to all samples for that day. Detection limits were 25 pmol/L for As(III) and As(III+V), and 50 pmol/L for MMAs and DMAs. Precision was better than 8% (relative standard deviation) for all As species. Alkaline phosphatase enzyme activity was measured using the fluorescence method of Ammerman (1993).

\n","processing":"

Samples analyzed in duplicate or triplicate and means computed.

\n","bcodmoProcessing":"","title":"Surface transects for arsenic speciation, antimony speciation, and alkaline phosphatase activity from R/V Knorr cruise KN204-01 in the Subtropical North Atlantic Ocean in 2011 (U.S. GEOTRACES NAT project)","nickname":"GT11 - As AP Surface Transects","dataUrl":"","currentState":"Final","currentStateId":"7","validated":true,"restricted":false,"version":"1","version_date":"2013-01-03T05:00:00.000Z","abstract":"Surface transects for arsenic speciation, antimony speciation, and alkaline phosphatase activity. Data for the concentrations of the dissolved (<0.4 µm) arsenic species: total inorganic As (III+V), arsenite (AsIII), As(V), monomethyl As, dimethyl As, and the activity of the enzyme alkaline phosphatase (unfiltered).","citation":"Cutter, G. (2020) Surface transects for arsenic speciation, antimony speciation, and alkaline phosphatase activity from R/V Knorr cruise KN204-01 in the Subtropical North Atlantic Ocean in 2011 (U.S. GEOTRACES NAT project). Biological and Chemical Oceanography Data Management Office (BCO-DMO). (Version 1) Version Date 2013-01-03 [if applicable, indicate subset used]. doi:10.26008/1912/bco-dmo.3830.1 [access date]","citationParts":{"identifier":"doi:10.26008/1912/bco-dmo.3830.1","versionDate":"2013-01-03","versionId":"1","year":"2020","title":"Surface transects for arsenic speciation, antimony speciation, and alkaline phosphatase activity from R/V Knorr cruise KN204-01 in the Subtropical North Atlantic Ocean in 2011 (U.S. GEOTRACES NAT project)","authors":"Cutter, G.","publisher":"Biological and Chemical Oceanography Data Management Office (BCO-DMO)."},"doi":"10.26008/1912/bco-dmo.3830.1","release_date":null,"field_dataset_location":"","temporal_extent":{"start":"2011-11-08T05:00:00.000Z","end":"2011-12-09T05:00:00.000Z"},"temporal":{"resolution":"time:unitDay","type":"time:Interval","start":{"value":"1320728400","label":"2011-11-08"},"end":{"value":"1323406800","label":"2011-12-09"}},"spatial_extent":{"shape":"polygon","center":{"latitude":28.0557,"longitude":-47.17215},"wkt":"POLYGON ((-69.8106 17.417, -24.5337 17.417, -24.5337 38.6944, -69.8106 38.6944, -69.8106 17.417))","north":38.6944,"east":-24.5337,"south":17.417,"west":-69.8106},"dataset_type":["Cruise Results"],"keywords":["oceans"],"data_files":[{"id":"899750","title":"As_AP_surface_GT11.csv","url":"https://datadocs.bco-dmo.org/dataset/3830/file/933jz08HRwDr0l/As_AP_surface_GT11.csv","showTableUrl":"https://www.bco-dmo.org/dataset/3830/data/view/899750","description":"Primary data file for dataset ID 3830","filename":"As_AP_surface_GT11.csv","bytesize":7991,"checksum":{"value":"0d4048be2f8f1bb009760b79274717a1","Algorithm":{"_id":"190","name":"MD5"}},"mimetype":"text/csv","fileType":{"_id":"192","name":"Comma Separated Values (.csv)"},"isErddap":"bcodmo_dataset_3830","date":"","isPublicDuringEmbargo":false,"primaryDataFile":true,"showTable":true,"restricted":false}],"supplemental_files":[],"roles":[{"role":{"_id":"138","name":"Principal Investigator"},"performedBy":{"_id":"50679","name":"Gregory A. Cutter"},"performedAtOrganization":{"_id":"49","name":"Old Dominion University"}},{"role":{"_id":"133","name":"Contact"},"performedBy":{"_id":"51337","name":"Oliver Wurl"},"performedAtOrganization":{"_id":"310","name":"Leibniz Institute for Baltic Sea Research Warnemunde Germany"}},{"role":{"_id":"145","name":"BCO-DMO Data Manager"},"performedBy":{"_id":"51103","name":"Theresa McKee"},"performedAtOrganization":{"_id":"191","name":"Woods Hole Oceanographic Institution"}}],"deployments":[{"_id":"58786","name":"KN204-01","synonyms":["GA03","GT11","KN204-01A","KN204-01B","USGT-NAT-2011","USGNAZT","GNAT","316N20111106","KN204-1"],"dates":{"start":"2011-11-06T00:00:00.000Z","end":"2011-12-11T00:00:00.000Z"},"platform":{"_id":"53994","name":"R/V Knorr"},"chiefScientists":[{"id":"50984","name":"Edward A. Boyle","role":"Chief Scientist"},{"id":"50679","name":"Gregory A. Cutter","role":"Co-Chief Scientist"}]}],"funding":[{"_id":"54753","name":"OCE-0926423","fundingSource":{"_id":"355","name":"NSF Division of Ocean Sciences"},"url":"https://www.nsf.gov/awardsearch/show-award?AWD_ID=0926423"},{"_id":"54938","name":"OCE-0926092","fundingSource":{"_id":"355","name":"NSF Division of Ocean Sciences"},"url":"https://www.nsf.gov/awardsearch/show-award?AWD_ID=0926092"}],"instruments":[{"_id":"5972","name":"Gas Chromatograph","description":"","type_id":"661","type_name":"Gas Chromatograph","type_desc":"Instrument separating gases, volatile substances, or substances dissolved in a volatile solvent by transporting an inert gas through a column packed with a sorbent to a detector for assay. (from SeaDataNet, BODC)","type_acronym":"Gas Chromatograph"},{"_id":"5971","name":"GeoFish","description":"","type_id":"549","type_name":"GeoFish Towed near-Surface Sampler","type_desc":"The GeoFish towed sampler is a custom designed near surface (2 meters or less) sampling system for the collection of trace metal clean seawater. It consists of a PVC encapsulated lead weighted torpedo and separate PVC depressor vane supporting the intake utilizing all PFA Teflon tubing connected to a deck mounted, air-driven, PFA Teflon dual-diaphragm pump which provides trace-metal clean seawater at up to 3.7L/min. The GeoFish is towed at up to 13kts off to the side of the vessel outside of the ship's wake to avoid possible contamination from the ship's hull. It was developed by Geoffrey Smith and Ken Bruland (University of California, Santa Cruz).","type_acronym":"GeoFish"},{"_id":"6018","name":"towed undulating vehicle","description":"","type_id":"604","type_name":"towed undulating vehicle","type_desc":"A towed undulating vehicle is a generic class of instruments. See the data set specific information for a detailed description. These are often prototype instrument packages designed to make very specific measurements.","type_acronym":"TUV"}],"parameters":[{"_id":"31493","name":"cruise_id","format":"","frictionlessType":"","description":"

cruise id

","units":{"_id":"","name":"text"},"type":{"_id":"1102","name":"cruise_id","description":"

cruise designation; name

"}},{"_id":"31494","name":"geofish_station","format":"","frictionlessType":"","description":"

towed fish station

","units":{"_id":"","name":"text"},"type":{"_id":"1960","name":"geofish_station","description":"

GEOTRACES towfish station

"}},{"_id":"31495","name":"date","format":"","frictionlessType":"","description":"

Date in the format YYYYMMDD

","units":{"_id":"","name":"unitless"},"type":{"_id":"1070","name":"date","description":"

date; generally reported in GMT as YYYYMMDD (year; month; day); also as MMDD (month; day); EqPac dates are local Hawaii time. ISO_Date format is YYYY-MM-DD (http://www.iso.org/iso/home/standards/iso8601.htm)

"}},{"_id":"31496","name":"time","format":"","frictionlessType":"","description":"

Time

","units":{"_id":"","name":"HHMM"},"type":{"_id":"1075","name":"time","description":"

Time GMT defined as HHMM; time of day; generally reported in GMT as HHMM (hours and minutes) but may also be HH.H (decimal hours) or HHMMSS (hours; minutes and seconds); in EqPac time is reported as Hawaii local time

"}},{"_id":"31497","name":"lat","format":"","frictionlessType":"","description":"

Latitude (South is negative)

","units":{"_id":"","name":"decimal degrees"},"type":{"_id":"730","name":"latitude","description":"

latitude, in decimal degrees, North is positive, negative denotes South; Reported in some datasets as degrees, minutes

"}},{"_id":"31498","name":"lon","format":"","frictionlessType":"","description":"

Longitude (West is negative)

","units":{"_id":"","name":"decimal degrees"},"type":{"_id":"731","name":"longitude","description":"

longitude, in decimal degrees, East is positive, negative denotes West; Reported in some datasets as degrees, minutes

"}},{"_id":"31499","name":"AsIII","format":"","frictionlessType":"","description":"

Arsenite (HAsO32-)

","units":{"_id":"","name":"nmol/L"},"type":{"_id":"1073","name":"no_bcodmo_term","description":"