
Title:  METADATA FOR STATION/ENVIRONMENTAL DATA SETS FROM PUMP CASTS
	COLUMBIA RIVER LMER PROJECT

Contact: Charles A. "Si" Simenstad
	Fisheries Research Institute
	University of Washington
	Box 357980
	Seattle, WA  98195-7980  USA
	email: csimenstad@lternet.edu

Principle Investigators (Institution) and research area: 
	Antonio Baptista (Oregon Graduate Inst. of Science & Technology)		hydrodynamics;
	John Baross (Univ. of Washington School of Oceanography)		microbiology;
	L.J. "Sam" Bledsoe (UC-Davis Civil and Environmental Engineering)	system modeling;
	David Jay (Oregon Graduate Inst. of Science & Technology)			geophysics;
	Fredrick Prahl (Oregon St. Univ. Oceanic and Atmospheric Sciences)	geochemistry;
	Denise Reed (Louisiana Universities Marine Consortium)		sediment transport;
	Charles A. "Si" Simenstad (Univ. Washington Fisheries Research Inst.) zooplankton;
	Lawrence Small (Oregon St. Univ. Oceanic and Atmospheric Sciences)	phytoplankton

Data Description: Pump casts were conducted immediately following a CTD cast and are, thus, cross-
referenced by CTD data parameters.  Pump samples were collected from usually three depths per cast (near-
surface, mid-depth, near-bottom), with PIs responsible for analyzing "core" parameters.  These data are 
critical for many aspects of the study as they are used to construct dynamic models of the estuarine turbidity 
maxima at different tidal and flow regimes.  See Simenstad et al. (1994) for a project overview.

Spatial and Temporal Resolution:  Pump cast sampling, and associated CTD casts took place from a fixed 
vessel during one 28-35 day cruise per year in 1990, 1991, 1992, 1995, and 1996.   During 1997 and early 1998, 
there were 2 week "seasonal" cruises in May, July, and October (1997) and February to March (1998).  During 1999, 
sampling was conducted for two weeks in June on the Columbia River and for two weeks in July on the Fraser River 
in British Columbia, Canada.

Methodology:  Measurements were conducted from an anchored vessel.  A Seabird (1990-1992) SBE 9/11 or Ocean Sensors 
(1995-1996) model OS-200 CTD equipped with a CT cell, OBS sensor, and a WetLabs AC-3 chlorophyll absorption-attenuation 
sensor were deployed for vertical profiles approximately every 30 minutes.  Water samples were collected with a pump 
attached to the CTD package immediately following a CTD cast.  CTDs were factory calibrated each year.  CTD data, unless 
otherwise noted, were taken on the downcast and the resulting salinity and temperature profiles were used to select pump 
depths on the following upcast.

Variables:
	Code		cast-specific code number (see below)
	Date		Date in MM/DD/YY format
	Time		Time of day (Pacific Standard Time)
	DegLatN		degrees north latitude
	MinLatN		minutes north latitude, decimal is tenths of minutes
	DegLongW	degrees west longitude
	MinLongW	minutes west longitude, decimal is tenths of minutes
	RiverKm		kilometer mark along river channel
	Bottle		nutrient bottle reference number
	Salinity	salinity
	Temp		temperature in degrees Celcius
	Depth		depth in meters
	Density		density (sigma-T)
	OBS		optical backscattering (see below)
	Fluor		chlorophyll a (mg/m^3) determined by fluorometer (1992 only)
	AC3chla		chlorophyll a (mg/m^3) determined by AC-3 (see below) 
	Atten		beam attenuation (1/m)
	Transmiss	transmissivity (% pure water)

Explanation of Code:
	Format of code is:  YYBSENN
		
		YY	first two digits indicate year
		B	letter(s) indicates boundary location or tidal series as follows: U=upstream 
(beyond salt wedge), D=downstream (below estuarine turbidity maximum), N=neap tide, S=spring tide, 
SN=spring-neap transition, E= ebb, F=flood, L=long time series, YB=Young's Bay, CB=Cathlamet Bay, P=Pitt 
River (Fraser only), T=Transect (Fraser only)
		S	number of sample series at that location/tidal stage
		E	event number (sequence) within that series (an 'E' or 'F' may follow this number 
indicating and ebb or flood tide sampling
		NN	two (or three) digits indicate CTD cast number that corresponds to the pump cast
		*	an asterisk after the code indicates CTD data taken from the downcast 
immediately prior to the pump cast

Other data notes:
	*** OBS units are linearly related to suspended particulate material as measured in mg/L.

	***  The AC-3 unit was used beginning in 1995; data sets since then will have a column for  this 
variable. The voltage reading from the AC-3 is transformed into a chlorophyll a value using the factory 
calibration coefficients.  The voltage signal is proportional to chlorophyll absorption after light passage 
through a series of filters contained within the AC-3 unit.

	*** In 1995, missing density data is denoted by a value of -10

	*** In 1995 and 1996, there was a malfunction in the AC-3 unit on the CTD.  This resulted in no 
chlorophyll or transmissometer readings.  Furthermore, temperature readings were affected at low salinities 
(< 1.0) and may be inaccurate by as much as +/- 0.2 degrees C.  It is unknown if/when these data can be 
reconstructed.  No chlorophyll sensor was employed in 1990 and 1991.

	*** In 1999, up to a 50cm offset may exist in the depth data.  The CTD's pressure offset varies 
slightly from cruise to cruise, and is typically less than 50cm.  Superimposed on this relatively constant 
offset, the effect of ordinary atmospheric pressure fluctuations is small, and varies from -10cm to 10cm 
(except perhaps in very strong low pressure systems.)  The pressure offset was not accounted for in the 1999 
cruise data.

File format: comma-delineated ASCII with header;
	maximum number of records = 1447;
	maximum number of data columns = 16

References:

Simenstad, CA, DJ Reed, DA Jay, JA Baross, FG Prahl, and LF Small. 1994. Land-Margin Ecosystem 
Research in the Columbia River Estuary: an interdisciplinary approach to investigating couplings between 
hydrological, geochemical and ecological processes within estuarine turbidity maxima. In: KR Dyer and RJ 
Orth, eds., Changes in fluxes in estuaries: Implications from science to management (ECSA22/ERF, 
Plymouth, September 1992). pp 437-444.  Olsen and Olsen, Fredensborg, Denmark.
 

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