Rabalais, N. 1989 Database Hydrographic data were collected during a August 12 -16, 1988 survey of the Louisiana continental shelf. Nutrient, pigment and station information data were also acquired. Drought conditions in the upper Mississippi River basin during the spring and summer of 1988 resulted in a significant reduction in the flow of the Mississippi River and an opportunity to document hydrographic conditions under low flow conditions and observe the effects of low flow on hypoxia. The physical, biological and chemical data collected are part of a long-term coastal Louisiana dataset. The goal is to understand physical and biological processes that contribute to the causes of hypoxia and use the data to support environmental models for use by resource managers. 19880812 Unknown 19880816 Unknown ground condition Complete As needed -92.39 -89.42 29.31 28.6 29.31 -92.39 28.6 -89.42 28.6 -92.39 29.31 -89.42 29.31 -92.39 Louisiana coastal waters, Northwestern Gulf of Mexico. GCMD NASA's Global Change Master Dir. THEME EARTH SCIENCE > Biosphere > Ecological Dynamics > Biogeochemical Cycles EARTH SCIENCE > Biosphere > Ecological Dynamics > Nutrient Cycling EARTH SCIENCE > Biosphere > Ecological Dynamics > Oxygen Demand EARTH SCIENCE > Biosphere > Ecological Dynamics > Primary Production EARTH SCIENCE > Human Dimensions > Environmental Impacts > Eutrophication EARTH SCIENCE > Hydrosphere > Water Quality EARTH SCIENCE > Hydrosphere > Water Quality > Chlorophyll EARTH SCIENCE > Hydrosphere > Water Quality > Conductivity EARTH SCIENCE > Hydrosphere > Water Quality > Light Transmission EARTH SCIENCE > Hydrosphere > Water Quality > Nitrogen Compounds EARTH SCIENCE > Hydrosphere > Water Quality > Nutrients EARTH SCIENCE > Hydrosphere > Water Quality > Oxygen EARTH SCIENCE > Hydrosphere > Water Quality > pH EARTH SCIENCE > Hydrosphere > Water Quality > Water Temperature EARTH SCIENCE > Oceans > Coastal Processes EARTH SCIENCE > Oceans > Marine Environment Monitoring EARTH SCIENCE > Oceans > Ocean Chemistry > Ammonia > Ammonium EARTH SCIENCE > Oceans > Ocean Chemistry > Biogeochemical Cycles EARTH SCIENCE > Oceans > Ocean Chemistry > Chlorophyll EARTH SCIENCE > Oceans > Ocean Chemistry > Nitrate EARTH SCIENCE > Oceans > Ocean Chemistry > Nitrite EARTH SCIENCE > Oceans > Ocean Chemistry > Nitrogen EARTH SCIENCE > Oceans > Ocean Chemistry > Nutrients EARTH SCIENCE > Oceans > Ocean Chemistry > Oxygen EARTH SCIENCE > Oceans > Ocean Chemistry > pH EARTH SCIENCE > Oceans > Ocean Chemistry > Phosphate EARTH SCIENCE > Oceans > Ocean Chemistry > Pigments EARTH SCIENCE > Oceans > Ocean Chemistry > Silicate EARTH SCIENCE > Oceans > Ocean Circulation > Fronts EARTH SCIENCE > Oceans > Ocean Optics > Secchi Depth EARTH SCIENCE > Oceans > Ocean Temperature EARTH SCIENCE > Oceans > Salinity/Density EARTH SCIENCE > Oceans > Water Quality GCMD NASA's Global Change Master Dir. PLACE Gulf Of Mexico North Atlantic Ocean United States Of America North America Northern Hemisphere Sea Surface None 1. Dataset credit required. 2. Experience with similar datasets has shown that when data are plotted or used in further analysis, outlying values may occasionally be discovered. Please report any possible problems with the data to N. Rabalais. Nancy N. Rabalais Louisiana Universities Marine Consortium mailing address

Louisiana Universities Marine Consortium 8124 Hwy 56

Chauvin LA 70344 USA 985 851 2800 985 851 2874 Unknown Rabalais, N.N., Turner, R.E., Wiseman Jr, W.J. and Boesch, D.F. Funding: Funds for the research were provided by the National Oceanographic and Atmospheric Administration, Ocean Assessments Division, through the Louisiana Sea Grant Program, the Louisiana Board of Regents Education Quality Support Fund and by the Louisiana Universities Marine Consortium. None Unclassified None Windows 2000, MSAccess 2000 Autoanalyzer Unknown. Tom Oswald mailing address

110 Coastal Studies Coastal Ecology Institute LSU

Baton Rouge LA 70803 225 388-6700 Unknown Fluorometer Contact Turner Designs. Turner Designs Inc. mailing address

845 W. Maude Avenue

Sunnyvale CA 94085 US 877 316-8049 CTD Contact Hydrolab Corporation. Hydrolab Corporation mailing address

8700 Cameron Road

Austin TX 78754 US 800-949-3766 techsupport@hydrolab.com A navigation device that uses a radio navigation system operated by the U.S. Coast Guard. Contact Northstar Technologies Inc. Northstar Technologies Inc. mailing address

Northstar Technologies

Acton Mass. 01720 978-897-6600 service@northstarcmc.co S888Hydro: Temperature, pH, dissolved oxygen, conductivity, salinity, and depth were measured with a Hydrolab Surveyor II Water Quality Data System at 1-, 2-, or 3-m intervals through the water column. Readings from a digital display unit were recorded on board ship. Conductivity in 25°C equivalents was converted to in situ conductivity and in situ salinity. Water samples were collected to check the conductivity sensor against water of a known salinity. A correction factor was applied as necessary for in situ salinity calculations. Selected samples for dissolved oxygen analysis were collected from surface and bottom waters and analyzed according to a modified Winkler procedure (Strickland and Parsons, 1972). Operation, maintenance, and calibration of the Hydrolab Surveyor II followed instructions provided by the Hydrolab manual (Hydrolab Corp., 1984). Yearly maintenance of the Surveyor II was performed by Hydrolab Corporation. S888Nutrient: Nutrient analyses were conducted by Tom Oswald under the supervision of R. E. Turner. S888Pigment: The Turner Designs model 10 fluorometer was calibrated for chlorophyll a against a chemical supply house chlorophyll a standard measured on a spectrophotometer yearly (or more frequently if needed). During the cruise, the fluorometer was blanked and calibrated daily in accordance with Turner Designs recommended procedures. Chlorophyll analyses followed a modified fluorometric technique as described in Strickland and Parsons (1972). Pigment measurements were supervised and quality controlled by Nancy Rabalais. N. Rabalais performed an additional procedure in quality-control/quality-assurance by evaluating relationships between the data in S888Hydro, S888Nutrient, S888Pigment and S888Stns. Unknown. Unknown. Station positions were logged from RV Acadiana's NorthStar LORAN C at the beginning of sampling operations. Manufacturer's accuracy claim is 30 meters 90% of the time. Wind, currents and tidal forces may have moved the ships from the beginning positions. Unknown Unknown Field Pigment Water for chlorophyll analyses was collected from surface and bottom waters in 5 liter Niskin bottles. Water samples were filtered immediately following collection onto GF/F (0.7micron) filters. The filters where immersed in 5ml of DMSO/90%Acetone (40:60) solution, allowed to extract for at least one hour in the dark, then measured pre and post-acidification. Field Station Locations Stations were occupied along ten generally North-South transects across the Louisiana coastal shelf and into Texas waters. Station depths ranged from 5 to 55 meters. The objective was to delimit and describe the area of midsummer bottom dissolved oxygen less than 2(mg/L). Biological, chemical and physical properties of the water are measured. Northern end stations of transects were chosen based on the survey vessel's minimum depth limits for each longitude. 1988 was a low flow year (see abstract). Transect Southern end-member station locations were based on 1985 - 1987 midsummer hypoxia survey historical station locations. Field Nutrient Water for nutrient analyses was collected from surface and bottom waters in 5-liter Niskin bottles. Care was taken that the collector's hands were clean and avoided touching the water. Three replicate sample vials and caps were triple rinsed with sample before vial filling and closing. Samples were not filtered. The sample vials were frozen for later analysis in the laboratory. Lab Nutrient Samples for nutrients were frozen on board ship for later analysis in the laboratory. Nitrogen and phosphorus were analyzed according to methods described in EPA publication EPA 600/4-79-020 (1979), method 350.1 was used for ammonia-N, method was used for 353.2 for nitrate/nitrite-N, and method 365.1 for phosphate-P. Silicate was analyzed according to Technicon Industrial method 186-72 W/B (1977). Unknown Point Point 43 0.0001 0.0001 Degrees and decimal minutes WGS84 WGS84 6378137 298.257223563 S888Hydro The table lists Hydrolab CTD station dissolved oxygen, temperature, specific conductance, salinity, pH, percent oxygen saturation and density values at depths. There are 423 records. None. Depth Depth of HydroLab pressure sensor Producer Defined 0.3 54.2 Meters 19880812 19880816 O2 Dissolved oxygen Producer defined 1.7 11.13 mg/L 19880812 19880816 PctO2Sat Oxygen percent saturation Producer defined 25.6 173 Percent 19880812 19880816 pH pH Producer defined. 7.4 8.2 pH units 19880812 19880816 Sal Salinity Producer defined 8.69 36.25 ppt 19880812 19880816 Sigma-t Density sigma-t Producer defined 2.54 25.73 Density sigma-t 19880812 19880816 spCond Conductivity Producer defined 15.13 55.13 mmho/cm 19880812 19880816 Sta Station name of location sampled Producer defined Character field 19880812 19880816 StnID Station identification number Producer defined 685 727 Integer 19880812 19880816 Temp Temperature Producer defined 20.01 30.8 Degrees centigrade 19880812 19880816 S888Nutrient The table lists station NH4, NO2, NO3, PO4 and SiO3 values at depths. There are 83records. None. Depth Depth of HydroLab p sensor Producer defined 0.3 54.2 Meters 19880812 19880816 NH4 Ammonium Producer defined 0.1 24.6 µg-at/L 19880812 19880816 NO2 Nitrite Producer defined 0.1 4.7 µg-at/L 19880812 19880816 NO3 Nitrate Producer defined 0 58.1 µg-at/L 19880812 19880816 PO4 Phosphate Producer defined 0.1 2.2 µg-at/L 19880812 19880816 SiO3 Silicate Producer defined 1 30.7 µg-at/L 19880812 19880816 Sta Station name of location sampled Producer defined Character field 19880812 19880816 StnID Station identification number Producer defined 685 727 Integer 19880812 19880816 S888Pigment The table lists station mean chlorophyll a, Fo/Fa ratio, and mean phaeopigment values at depths. There are 83 records. None. Depth Depth of HydroLab p sensor Producer defined 0.3 54.2 Meters 19880812 19880816 MeanC Mean Chlorophyll a Producer defined 0.2 45.7 µg/L 19880812 19880816 MeanF Mean Fo/Fa ratio Producer defined 1.3 16.8 FoFa ratio 19880812 19880816 MeanP Mean Phaeopigments Producer defined 0 6.4 µg/L 19880812 19880816 Sta Station name of location sampled Producer defined Character field 19880812 19880816 StnID Station identification number Producer defined 685 727 Integer 19880812 19880816 S888Stns The table lists station, date, latitude, longitude, Secchi disk, time of HydroLab cast and station ID. There are 43 records. None. Date Date station was sampled. Producer defined. 19880812 19880816 YYYYMMDD 19880812 19880816 Latitude Latitude of sampling station. Producer defined. 28.6083 29.3083 Decimal degrees 19880812 19880816 -9999 Latitude value was recorded from the ship's LORAN C at the beginning of sampling operations. Manufacturer's accuracy claim is 30 meters 90% of the time. Wind, currents and tidal forces may move the ship from the beginning position. Survey vessel was not anchored during sampling. Position at end of sample operations may have changed from beginning operations location. Vessel drift was generally less than 0.3 nm. An Accuracy value of -9999 was entered because accuracy could not be determined. Longitude Longitude of sampling station. Producer defined. -92.3833 -89.4267 Decimal degrees 19880812 19880816 -9999 Latitude value was recorded from the ship's LORAN C at the beginning of sampling operations. Manufacturer's accuracy claim is 30 meters 90% of the time. Wind, currents and tidal forces may move the ship from the beginning position. Survey vessel was not anchored during sampling. Position at end of sample operations may have changed from beginning operations location. Vessel drift was generally less than 0.3 nm. An Accuracy value of -9999 was entered because accuracy could not be determined. Secchi Secchi disk depth. Producer defined. 1.3 18.5 meters 19880812 19880816 Sta Station name of location sampled. Producer defined. Character field 19880812 19880816 StnID Station identification number. Producer defined. 685 727 Integer 19880812 19880816 Time Time of beginning of HydroLab CTD cast. Producer defined. 7:00:00 23:10:00 HH:mm 19880812 19880816 The related data tables S888Hydro, S888Nutrient, S888Pigment, and S888Stns contain spatial, temporal, physical and biological water quality data acquired during the August 1988 cruise. Each table contains a StnID field that can be used to key joins with the other tables. For detailed attribute information contact Nancy Rabalais. Nancy N. Rabalais Louisiana Universities Marine Consortium mailing address

Louisiana Universities Marine Consortium 8124 Hwy 56

Chauvin LA 70344 USA 985 851 2800 985 851 2874 Unknown I, the data requestor, agree to credit the data originators in any publications, reports or presentations generated from this data. I also accept that although these data have been processed successfully on a computer system at the Louisiana Universities Marine Consortium, no warranty expressed or implied is made regarding the accuracy or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. I recognize that these data are best acquired from the originator and not from a secondary source. I recognize that careful attention must be paid to the contents of the metadata file associated with these data. I will not hold Louisiana Universities Marine Consortium liable for improper or incorrect use of the data described and/or contained herein. This disclaimer applies both to individual use of the data and aggregate use with other data. MDB 9 File compression not used. 0.26 3-1/2 inch floppy disk DOS Copy S888.mdb Contact Distributor. None Call, email or write the Distributor with requests for data sets. None. Contact distributor 20020513 20020628 20120615 Ben Cole Louisiana Universities Marine Consortium mailing address

LUMCON 8124 Hwy 24

Chauvin LA 70344 USA 985 851 2800 985 851 2874 Unknown FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998 local time