CTD profile data from R/V Endeavor cruise EN509 in May-June 2012 in the Gulf of Mexico (GoMX - N2 Fixation project)

Website: https://www.bco-dmo.org/dataset/4067
Version: 04 April 2013
Version Date: 2013-04-04

Project
» Nitrogen fixation, nutrient supply and biological production in the Gulf of Mexico (GoMX - N2 Fixation)

Programs
» Gulf of Mexico - Deepwater Horizon Oil Spill (GoMX - DHOS)
» Ocean Carbon and Biogeochemistry (OCB)
ContributorsAffiliationRole
Montoya, JosephGeorgia Institute of Technology (GA Tech)Principal Investigator, Contact
Gegg, Stephen R.Woods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager


Dataset Description

CTD profile data - EN509


Processing Description

BCO-DMO Processing Notes
Original file: "EN509-BinnedProfiles-downcast.xls.zip" contributed by Joseph Montoya
- Header records generated
- Parameter names edited to conform to BCO-DMO parameter naming conventions


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Parameters

ParameterDescriptionUnits
CruiseIdCruise Id text
Op_NumberOperation Number xxx.xx
StnStation Number (First 3 digits of Op_Number) dimensionless
EvtEvent Number (Last digits after decimal point of Op_Number) dimensionless
Date_LocalDate Local YYYYMMDD
Time_LocalTime Local HHMM
ISO_DateTime_UTCDate/Time UTC YYYY-MM-DDTHH:MM:SS.00Z
LatitudeLatitude (South is negative) decimal degrees
LongitudeLongitude (West is negative) decimal degrees
Lease_BlockLease Block text
OperationOperation text
Seq_NumberSequence Number dimensionless
BCO_DMO_NoteBCO-DMO Data Manager note relating to CTD Profile data text
NotesActivity and Comments text
ScanScan dimensionless
TimeJJulian Time of Day xxx.xx
TimeSElapsed Time seconds
PrDMPressure decibars
DepSMDepth meters
T0Temp 0 - ITS-90 Degrees Celsius
T1Temp 1 - ITS-90 Degrees Celsius
T2_minus_T1Temp2 - Temp1 Degrees Celsius
C0Conductivity 0 Siemens/meter
C1Conductivity 1 Siemens/meter
C2_minus_C1Conductivity 2 - Conductivity 1 Siemens/meter
V0V0 volts
BatBeam Attenuation 1/m
XmissBeam Transmission percentage
V2V2 volts
AltMAltitude meters
V3V3 volts
ParPAR - Photosynthetically Available [Active] Radiation (tbd)
V4V4 volts
Sbeox0VOxygen 0 SBE 43 volts volts
V5V5 volts
Sbeox1VOxygen 1 SBE 43 volts volts
V1V1 volts
FlECO_AFLflECO-AFL: Fluorescence Wetlab ECO-AFL/FL Mg/m^3
SparSPAR - Surficial Photosynthetically Available [Active] Radiation (tbd)
PumpsPumps dimensionless
LatLatitude (South is negative) decimal degrees
LonLongitude (West is negative) decimal degrees
DepSM_BinDepth Binned meters
Sal00Salinity 0 PSU
Sal11Salinity 1 PSU
Sigma_E00Density 0 - sigma-theta Kg/m^3
Sigma_E11Density 1 - sigma-theta Kg/m^3
Sbeox0Oxygen 0 SBE 43 Mg/l
Sbeox1Oxygen 1 SBE 43 Mg/l
Potemp0Potential Temperature 0 Degrees Celsius
Potemp1Potential Temperature 1 Degrees Celsius
SvCMSound Velocity centimeters/second
SvCM1Sound Velocity 1 centimeters/second
Dz_to_dtdescent rate meters/second
GpaGpa (tbd)
NbinNbin dimensionless
FlagFlag dimensionless


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Instruments

Dataset-specific Instrument Name
Biospherical Instruments models QSP200L/QSR-240
Generic Instrument Name
Photosynthetically Available Radiation Sensor
Dataset-specific Description
Biospherical Instruments models QSP200L/QSR-240
Generic Instrument Description
A PAR sensor measures photosynthetically available (or active) radiation. The sensor measures photon flux density (photons per second per square meter) within the visible wavelength range (typically 400 to 700 nanometers). PAR gives an indication of the total energy available to plants for photosynthesis. This instrument name is used when specific type, make and model are not known.

Dataset-specific Instrument Name
Benthos model PSA-916
Generic Instrument Name
Altimeter
Dataset-specific Description
Benthos model PSA-916
Generic Instrument Description
An instrument that measures height above a fixed surface. The data can be used to map ocean-surface topography and generate gridded surface height fields.

Dataset-specific Instrument Name
Sea-Bird SBE-3 Temperature Sensor
Generic Instrument Name
Sea-Bird SBE-3 Temperature Sensor
Dataset-specific Description
SBE model 3
Generic Instrument Description
The SBE-3 is a slow response, frequency output temperature sensor manufactured by Sea-Bird Electronics, Inc. (Bellevue, Washington, USA). It has an initial accuracy of +/- 0.001 degrees Celsius with a stability of +/- 0.002 degrees Celsius per year and measures seawater temperature in the range of -5.0 to +35 degrees Celsius. more information from Sea-Bird Electronics

Dataset-specific Instrument Name
Sea-Bird SBE-4 Conductivity Sensor
Generic Instrument Name
Sea-Bird SBE-4 Conductivity Sensor
Dataset-specific Description
SBE model 4
Generic Instrument Description
The Sea-Bird SBE-4 conductivity sensor is a modular, self-contained instrument that measures conductivity from 0 to 7 Siemens/meter. The sensors (Version 2; S/N 2000 and higher) have electrically isolated power circuits and optically coupled outputs to eliminate any possibility of noise and corrosion caused by ground loops. The sensing element is a cylindrical, flow-through, borosilicate glass cell with three internal platinum electrodes. Because the outer electrodes are connected together, electric fields are confined inside the cell, making the measured resistance (and instrument calibration) independent of calibration bath size or proximity to protective cages or other objects.

Dataset-specific Instrument Name
Wet Labs WETStar flow through
Generic Instrument Name
Fluorometer
Dataset-specific Description
Wet Labs WETStar flow through
Generic Instrument Description
A fluorometer or fluorimeter is a device used to measure parameters of fluorescence: its intensity and wavelength distribution of emission spectrum after excitation by a certain spectrum of light. The instrument is designed to measure the amount of stimulated electromagnetic radiation produced by pulses of electromagnetic radiation emitted into a water sample or in situ.

Dataset-specific Instrument Name
Wet Labs C-Star 25-cm
Generic Instrument Name
Transmissometer
Dataset-specific Description
Wet Labs C-Star 25-cm
Generic Instrument Description
A transmissometer measures the beam attenuation coefficient of the lightsource over the instrument's path-length. This instrument designation is used when specific manufacturer, make and model are not known.

Dataset-specific Instrument Name
SBE 43 Dissolved Oxygen Sensor
Generic Instrument Name
Sea-Bird SBE 43 Dissolved Oxygen Sensor
Dataset-specific Description
SBE 43 Dissolved Oxygen Sensor
Generic 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

Dataset-specific Instrument Name
CTD Sea-Bird SBE 911plus
Generic Instrument Name
CTD Sea-Bird SBE 911plus
Dataset-specific Description
CTD Sea-Bird SBE 911plus
Generic Instrument Description
The Sea-Bird SBE 911plus is a type of CTD instrument package for continuous measurement of conductivity, temperature and pressure. The SBE 911plus includes the SBE 9plus Underwater Unit and the SBE 11plus Deck Unit (for real-time readout using conductive wire) for deployment from a vessel. The combination of the SBE 9plus and SBE 11plus is called a SBE 911plus. The SBE 9plus uses Sea-Bird's standard modular temperature and conductivity sensors (SBE 3plus and SBE 4). The SBE 9plus CTD can be configured with up to eight auxiliary sensors to measure other parameters including dissolved oxygen, pH, turbidity, fluorescence, light (PAR), light transmission, etc.). more information from Sea-Bird Electronics

Dataset-specific Instrument Name
Wet Labs ECO-AFL/FL Fluorometer
Generic Instrument Name
Wet Labs ECO-AFL/FL Fluorometer
Dataset-specific Description
Wet Labs ECO Chlorophyll Fluorometer
Generic Instrument Description
The Environmental Characterization Optics (ECO) series of single channel fluorometers delivers both high resolution and wide ranges across the entire line of parameters using 14 bit digital processing. The ECO series excels in biological monitoring and dye trace studies. The potted optics block results in long term stability of the instrument and the optional anti-biofouling technology delivers truly long term field measurements. more information from Wet Labs


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Deployments

EN509

Website
Platform
R/V Endeavor
Start Date
2012-05-25
End Date
2012-06-20
Description
Original data are available from the NSF R2R data catalog


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Project Information

Nitrogen fixation, nutrient supply and biological production in the Gulf of Mexico (GoMX - N2 Fixation)

Coverage: Northern Gulf of Mexico


From the NSF proposal abstract
This project will study the interplay of physical, chemical, and biological factors in supplying nitrogen, an essential nutrient, to temperate coastal and offshore waters of the Gulf of Mexico. The Gulf is an economically important but understudied marginal sea with major commercial and recreational fisheries as well as extensive fossil fuel deposits. Diazotrophic (N2-fixing) cyanobacteria bloom regularly in offshore and coastal waters of the Gulf and the limited data suggest that they contribute significant quantities of both nitrogen and carbon to the pelagic food web. These diazotrophs may play also a critical role in supplying N to other organisms, including the ichthyotoxic red tide dinoflagellate Karenia brevis. Despite its importance, little is currently known of the factors that promote N2-fixation in the Gulf or the relative significance of different physical and biological processes in creating conditions that favor N limitation in the water column. The Gulf of Mexico is strongly influenced by both riverine inputs and advective processes, providing an excellent model system for studying nutrient dynamics, physical forcing of productivity, terrestrial-oceanic linkages, and the potential impact of land use and climate change on marine ecosystems.

The relatively small basin of the Gulf of Mexico provides an opportunity to quantify and study interactions among physical, chemical, and biological processes relevant to a broad range of other coastal and oceanic systems. Land-use and climate change are likely to affect the circulation and hydrography of the Gulf, as well as the magnitude and nature of riverine inputs, all with uncertain impacts on the biogeochemistry of the Gulf of Mexico. This research will provide timely insights into these processes and will generate a baseline of understanding for evaluating and predicting the impact of future land use and climate changes in the system. This project will make an important contribution to our understanding of the factors that regulate N2-fixation and its role in supporting the biota in temperate waters. The following specific goals are included in the work:

1. Identify the major diazotroph groups in the Gulf of Mexico and characterize their distribution and activity in different regions and water masses.

2. Quantify the impact of advective processes, mesoscale features, and riverine inputs on nutrient limitation and N2-fixation in the Gulf, and evaluate the controls on N2-fixation and the degree of spatial and temporal niche differentiation among diazotroph assemblages in different regions affected by these processes.

3. Use satellite data and physical models to scale up our measurements spatially and to evaluate the regional significance of N2-fixation in the Gulf of Mexico. The researchers will also use a coupled physical/biological model to explore variability in the physical forcing and the potential impact of likely land use and climate change scenarios in altering nutrient dynamics and N2-fixation in the Gulf of Mexico.

The investigators and their institutions have a strong commitment to undergraduate and graduate education. This project includes support for graduate students, a technician, and undergraduates. In addition to peer-reviewed papers and websites, workshops aimed at K-12 teachers, and a program involving high school teachers in research will be used to disseminate the results of this project broadly in the local community. The investigators are committed to increasing the diversity of the ocean science community and are active in recruiting and training efforts at their institutions.



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Program Information

Gulf of Mexico - Deepwater Horizon Oil Spill (GoMX - DHOS)

Coverage: Northern Gulf of Mexico


Grants for Rapid Response Research (RAPID)
The RAPID funding mechanism is used for proposals having a severe urgency with regard to availability of, or access to data, facilities or specialized equipment, including quick-response research on natural or anthropogenic disasters and similar unanticipated events.
 

GOM - Broader Impacts
The need to understand the impact of this largest oil spill to date on ecosystems and biochemical cycling is self evident. The consequences of the disaster and accompanying clean up measures (e.g. the distribution of dispersants) need to be evaluated to guide further mediating measures and to develop and improve responses to similar disasters in the future. Would it be advantageous if such oil aggregates sink, or should it rather remain suspended? Possibly measures can be developed to enhance sinking or suspension (e.g. addition of ballast minerals) once we understand their current formation and fate. Understanding the particle dynamics following the input of large amounts of oil and dispersants into the water is a prerequisite to develop response strategies for now and in the future.


Ocean Carbon and Biogeochemistry (OCB)


Coverage: Global


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.



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Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)

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