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    Alongtrack data from ship's Data Acquisition System (DAS) from R/V Thomas G. Thompson cruise TN277 in the Eastern North Pacific Ocean in 2012 (POWOW project)

Alongtrack data from ship's Data Acquisition System (DAS) from R/V Thomas G. Thompson cruise TN277 in the Eastern North Pacific Ocean in 2012 (POWOW project)

Website: https://www.bco-dmo.org/dataset/3758
Data Type: Cruise Results
Version: 1
Version Date: 2012-10-24

» Seasonal and decadal changes in temperature drive Prochlorococcus ecotype distribution patterns (POWOW)
Johnson, Zackary I.Duke UniversityChief Scientist, Contact
Zinser, ErikUniversity of Tennessee Knoxville (UTK)Co-Chief Scientist
Rauch, ShannonWoods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager

Alongtrack data from ship's Data Acquisition System (DAS) from R/V Thomas G. Thompson cruise TN277 in the Eastern North Pacific Ocean in 2012. Data were collected along the cruise track from the ship's IMET sensors, thermosalinograph, Knudesn, and GPS.


Spatial Extent: N:32.70665 E:-117.225355 S:21.247275 W:-158.342478
Temporal Extent: 2012-03-01 - 2012-03-11

Dataset Description

Data collected along the cruise track from the ship's IMET sensors, thermosalinograph, Knudesn, and GPS. Unprocessed ADCP, gravity, and multibeam underway data are also available from BCO-DMO upon request by emailing info@bco-dmo.org. These are raw data that cannot be served online in their current format.

Acquisition Description

The DAS system collects data at an operator selected interval; this interval is usually set at 1 sample every 5 seconds. The data are collected from IMET sensors, SBE-21 Thermosalinagraph, EM302 or Knudsen, C-Nav GPS and Winch systems. The data are time, date and position tagged. A new file is started each day at GMT 0:00 and ends at 23:59:55 (depending on the data storage interval). Filename extensions are Julian Day. (From University of Washington vessel information)

Thermosalinograph calibration data for DAS data follows:
Conductivity calibration coefficients:
m = 4.6
a = 0.00000523250085
b = 0.49686504
c = -4.21206317
d = -0.0000877310216

Temperature calibration coefficients:
f = 2610.082
a = 0.00364763429
b = 0.000596620785
c = 0.0000159326489
d = 0.00000120111676

External Temperature calibration coefficients:
f = 2676.423
a = 0.00368121106
b = 0.00058938925
c = 0.0000151014632
d = 0.00000122956892

PAR sensor calibration coefficient:
dry = 1.63E-17

Processing Description

BCO-DMO made the following modifications:
- Parameter names were changed to conform to BCO-DMO conventions.
- Blanks were replaced with 'nd'.
- + signs preceding latitude values were removed.
- lat and lon values that were obviously erroneous were replaced with 'nd' (e.g. negative latitude values, longitude values of -500).
- humidity and sea surface temperature columns were removed because all values were nd (humidity) and -9.999, or -2 (sea surface temp).
- Values containing unreadable characters were replaced with 'nd'.

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yrdayYearday (GMT). unitless
month_gmtMonth of year (GMT). mm (01 to 12)
day_gmtDay of month (GMT). dd (01 to 31)
year4-digit year. in YYYY format unitless
time_gmtNav computer GMT time. HH:MM:SS
date_gmtNav computer GMT date. format: dd-mm-YYYY unitless
latNav computer latitude; positive = north. decimal degrees
lonNav computer longitude; positive = east. decimal degrees
tempThermosalinograph temperature. degrees Celsius
condThermosalinograph conductivity. Seimens/meter
salThermosalinograph salinity. PSU
depth_wWater depth. meters
chl_rawThermosalinograph chlorophyll. volts
light_trans_vThermosalinograph light transmission. volts
PARPAR in microEinsteins per square meter per second. uE/m^2/sec
radiation_sIMET short wave radiation. watts/square meter
temp_airIMET air temperature. degrees Celsius
press_barIMET barometric pressure millibars
wind_speedTrue wind speed. knots
wind_dirTrue wind direction. degrees
wind_speed_rRelative wind speed. knots
wind_dir_rRelative wind direction. degrees
wind_speed_avgAverage true wind speed. knots
wind_dir_avgAverage true wind direction. degrees
sound_velSound velocity. meters/second
headGyro compass heading degrees true
cogNav computer course over ground. degrees true
speedlogDoppler speed log. knots
sogNav computer speed over ground. knots
winch_noWinch ID number: 0 = Hydro Winch 1; 1 = Trawl Winch; 2 = Hydro Winch 2. unitless
wire_outNumber of meters of wire out. meters
wire_rateWire rate. meters/minute
wire_tensionWire tension in pounds. lbs
ISO_DateTime_UTCDate/Time (UTC) ISO8601 formatted. T indicates start of time string; Z indicates UTC. yyyy-MM-dd'T'HH:mm:ss'Z'

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Dataset-specific Instrument Name
Generic Instrument Name
Dataset-specific Description
SBE 21 SeaCAT Thermosalinograph measured conductivity and temperature. Refer to the following (PDFs) from the TN277 (POWOW1) cruise:Temperature calibration dataTemperature calibration reportConductivity calibration dataConductivity calibration report
Generic Instrument Description
A thermosalinograph (TSG) is used to obtain a continuous record of sea surface temperature and salinity. On many research vessels the TSG is integrated into the ship's underway seawater sampling system and reported with the underway or alongtrack data.

Dataset-specific Instrument Name
Generic Instrument Name
Dataset-specific Description
See the WetLabs ECO Fluorometer chacterization sheet (PDF) from TN277 (POWOW1) cruise.
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 CSTAR Transmissometer
Generic Instrument Name
Wet Labs CSTAR Transmissometer
Dataset-specific Description
See the WetLabs C-Star calibration sheet (PDF) from the TN277 (POWOW1) cruise.
Generic Instrument Description
A highly integrated opto-electronic design to provide a low cost, compact solution for underwater measurements of beam transmittance. The instrument is capable of either free space measurements, or through the use of an optical flow tube, flow-through sampling with a pump. It can be used in profiling, moored, or underway applications. more information from Wet Labs

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R/V Thomas G. Thompson
Start Date
End Date
The POWOW#1 cruise was a trip of opportunity to sample along temperature gradients and test out new protocols. The primary goal of this cruise was to measure the abundance, diversity and activity of Prochlorococcus and associated bacterial and viral communities across temperature (and other environmental) gradients to understand how climate change may impact ocean ecology and biogeochemistry. There are many additional scientific and broader impact goals including characterizing oxidative stress and investigating nitrogen uptake/utilization molecular diversity. Cruise information and original data are available from the NSF R2R data catalog.

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Project Information

Seasonal and decadal changes in temperature drive Prochlorococcus ecotype distribution patterns (POWOW)

Coverage: Eastern North Pacific Ocean

Project also known as 'Prochlorococcus Of Warming Ocean Waters' (POWOW). The two numerically-dominant ecotypes of the marine cyanobacterium Prochlorococcus partition the surface ocean niche latitudinally, with ecotype eMIT9312 dominant in the 30 degree N to 30 degree S region and eMED4 dominant at higher latitudes. These ecotypes may account for 25-50% of primary production in open ocean ecosystems, but this percentage is dependent on which ecotype dominates. The relative abundance of the two ecotypes follows a log-linear relationship with temperature, with the transition from eMIT9312 to eMED4 occurring at approx. 18 degrees C. From these descriptive data, it has been hypothesized that temperature is the primary driver of relative abundance. Their contribution to net primary production, however, appears to be independent of temperature, suggesting temperature regulates ecotype dominance through photosynthesis-independent mechanisms. To test these hypotheses, the PIs are undertaking a series of field and lab studies to investigate the effect of temperature change on the distribution of these ecotypes. Two cruises in the North Pacific will trace the transitions from eMIT9312- to eMED4-dominated regions, with one cruise during the winter and the other during summer. They have hypothesized that the ratio of ecotype abundance will move latitudinally with the seasonal shift in temperature gradient: migration of the 18 degrees C isotherm northward in the summer will be matched by a similar migration of the 1:1 ecotype transition point. Multiple crossings of the 18 degrees C isotherm are proposed, and the summer cruise will also follow the isotherm to the Western US coast to gain insight on physical and geochemical influences. Environmental variables such as nutrient concentrations, light/mixing depths, and virus /grazing based mortality, which may impinge on the relationship between temperature and ecotype ratio, will be assessed through a series of multivariate analyses of the collected suite of physical, chemical and biological data. Seasonal comparisons will be complemented with on-deck incubations and lab competition assays (using existing and new isolates) that will establish, for the first time, how fitness coefficients of these ecotypes relate to temperature. As latitudinal shifts in temperature gradient and migration of ecotypes during seasonal warming likely share common features with high latitude warming as a consequence of climate change, the investigator's analyses will contribute important biological parameters (e.g., abundances, production rates, temperature change coefficients) for modeling biological and biogeochemical responses to climate change. This research will be integrated with that of committed collaborators, generating data sufficient for ecosystem-scale characterizations of the contributions of temperature (relative to other forcing factors) in constraining the range and seasonal migration of these numerically dominant marine phototrophs. Publications produced as result of this research: Rowe, J.M., DeBruyn, J.M., Poorvin, L., LeCleir, G.R., Johnson, Z.I., Zinser, E.R., and Wilhelm, S.W. 2012. Viral and bacterial abundance and production in the Western Pacific Ocean and the relation to other oceanic realms. FEMS Microbiology Ecology, 72, p. 359. DOI: 10.1111/j.1574-6941.2011.01223.x Morris, J.J., Lenski, R.E. and E.R. Zinser. 2012. The Black Queen Hypothesis: Evolution of Dependencies through Adaptive Gene Loss. mBio, 3, p. e00036-12. DOI: 10.1128/mBio.00036-12 Morris, J.J., Johnson, Z.I., Szul, M.J., Keller, M., and Zinser, E.R. 2011. Dependence of the cyanobacterium Prochlorococcus on hydrogen peroxide scavenging microbes for growth at the ocean's surface. PLoS One, 6(2), p. 16805. DOI:10.1371/journal.pone.0016805 Ringuet, S., Sassano, L., and Johnson, Z.I. 2011. A suite of microplate reader-based colorimetric methods to quantify ammonium, nitrate, orthophosphate and silicate concentrations for aquatic nutrient monitoring. Journal of Environmental Monitoring. DOI:10.1039/C0EM00290A Ritchie, A.E. and Johnson, Z.I. 2012. Abundance and genetic diversity of aerobic anoxygenic phototrophic bacteria of coastal regions of the Pacific Ocean. Applied and Environmental Microbiology, 78, p. 2858. DOI: 10.1128/AEM.06268-11

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Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)
NSF Division of Ocean Sciences (NSF OCE)

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This document is created by info v 4.1f 5 Oct 2018 from the content of the BCO-DMO metadata database.    2020-02-21  19:55:50