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Dataset Title:  M01 SUNA - Nitrate Observations Corrected   RSS
Institution:  University of Maine School of Marine Sciences   (Dataset ID: M01_corrected_nitrate_csv)
Information:  Summary ? | License ? | FGDC | ISO 19115 | Metadata | Background | Subset | Make a graph
Variable ?   Optional
Constraint #1 ?
Constraint #2 ?
   Minimum ?
   or a List of Values ?
   Maximum ?
 station ?              
 time (UTC) ?          2013-06-23T16:45:00Z    2021-03-24T00:45:00Z
  < slider >
 Year ?      
   - +  ?
 Month ?          1    12
 Day ?          1    31
 Hour ?          0    20
 Minute ?          44    45
 Second ?          0    0
 Nitrate_umol (umol) ?          -0.484    24.93
 Standard_Deviation (Standard Deviation(umol)) ?          0.0    1.998
 Nitrate (mol m-3) ?          -4.84E-4    0.045
 latitude (degrees_north) ?          43.4907    43.491
  < slider >
 longitude (degrees_east) ?          -67.88    -67.8798
  < slider >
 mooring_site_desc ?              
 depth (m) ?      
   - +  ?
  < slider >
 water_depth (m) ?          285.0    285.0
Server-side Functions ?
 distinct() ?
? (" ")

File type: (more info)

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The Dataset Attribute Structure (.das) for this Dataset

Attributes {
 s {
  station {
    String ioos_category "Identifier";
    String long_name "Station";
  time {
    String _CoordinateAxisType "Time";
    Float64 actual_range 1.3720059e+9, 1.6165467e+9;
    String axis "T";
    String ioos_category "Time";
    String long_name "Time";
    String standard_name "time";
    String time_origin "01-JAN-1970 00:00:00";
    String units "seconds since 1970-01-01T00:00:00Z";
  Year {
    Int16 actual_range 2013, 2021;
    String ioos_category "Time";
    String long_name "Year";
  Month {
    Byte actual_range 1, 12;
    String ioos_category "Time";
    String long_name "Month";
  Day {
    Byte actual_range 1, 31;
    String ioos_category "Time";
    String long_name "Day";
  Hour {
    Byte actual_range 0, 20;
    String ioos_category "Time";
    String long_name "Hour";
  Minute {
    Byte actual_range 44, 45;
    String ioos_category "Time";
    String long_name "Minute";
  Second {
    Byte actual_range 0, 0;
    String ioos_category "Time";
    String long_name "Second";
  Nitrate_umol {
    Float32 actual_range -0.484, 24.93;
    Float64 colorBarMaximum 50.0;
    Float64 colorBarMinimum 0.0;
    String ioos_category "Dissolved Nutrients";
    String long_name "Mole Concentration Of Nitrate In Sea Water";
    String standard_name "mole_concentration_of_nitrate_in_sea_water";
    String units "umol";
  Standard_Deviation {
    Float32 actual_range 0.0, 1.998;
    Float64 colorBarMaximum 50.0;
    Float64 colorBarMinimum 0.0;
    String ioos_category "Statistics";
    String long_name "Standard Deviation(umol)";
  Nitrate {
    Float32 actual_range -4.84e-4, 0.045;
    Float64 colorBarMaximum 50.0;
    Float64 colorBarMinimum 0.0;
    String ioos_category "Dissolved Nutrients";
    String long_name "Mole Concentration Of Nitrate In Sea Water";
    String standard_name "mole_concentration_of_nitrate_in_sea_water";
    String units "mol m-3";
  latitude {
    String _CoordinateAxisType "Lat";
    Float64 actual_range 43.4907, 43.491;
    String axis "Y";
    Float64 colorBarMaximum 90.0;
    Float64 colorBarMinimum -90.0;
    String ioos_category "Location";
    String long_name "Latitude";
    String standard_name "latitude";
    String units "degrees_north";
  longitude {
    String _CoordinateAxisType "Lon";
    Float64 actual_range -67.88, -67.8798;
    String axis "X";
    Float64 colorBarMaximum 180.0;
    Float64 colorBarMinimum -180.0;
    String ioos_category "Location";
    String long_name "Longitude";
    String standard_name "longitude";
    String units "degrees_east";
  mooring_site_desc {
    String ioos_category "Location";
    String long_name "Mooring Site Desc";
  depth {
    String _CoordinateAxisType "Height";
    String _CoordinateZisPositive "down";
    Int16 actual_range 1, 250;
    String axis "Z";
    Float64 colorBarMaximum 8000.0;
    Float64 colorBarMinimum -8000.0;
    String colorBarPalette "TopographyDepth";
    String ioos_category "Location";
    String long_name "Depth";
    String positive "down";
    String standard_name "depth";
    String units "m";
  water_depth {
    Float32 actual_range 285.0, 285.0;
    String ioos_category "Location";
    String long_name "Water Depth";
    String units "m";
    String cdm_data_type "Point";
    String Conventions "COARDS, CF-1.6, ACDD-1.3";
    String creator_email "[email protected]";
    String creator_name "David Townsend";
    String creator_url "";
    String defaultGraphQuery "time,Nitrate_umol&time%3E=max(time)-7days&depth=50&.draw=lines&.color=0x000000";
    Float64 Easternmost_Easting -67.8798;
    String featureType "Point";
    Float64 geospatial_lat_max 43.491;
    Float64 geospatial_lat_min 43.4907;
    String geospatial_lat_units "degrees_north";
    Float64 geospatial_lon_max -67.8798;
    Float64 geospatial_lon_min -67.88;
    String geospatial_lon_units "degrees_east";
    Float64 geospatial_vertical_max 250.0;
    Float64 geospatial_vertical_min 1.0;
    String geospatial_vertical_positive "down";
    String geospatial_vertical_units "m";
    String history 
"2024-02-25T01:01:22Z (local files)
    String infoUrl "";
    String institution "University of Maine School of Marine Sciences";
    String keywords "buoy, chemistry, concentration, data, day, depth, desc, deviation, dissolved, dissolved nutrients, e01, earth, Earth Science > Oceans > Ocean Chemistry > Nitrate, hour, identifier, latitude, longitude, maine, minute, mole, mole_concentration_of_nitrate_in_sea_water, month, mooring, mooring_site_desc, n02, nitrate, Nitrate_moles_m_3, Nitrate_umol, no3, nutrients, ocean, oceans, science, sea, seawater, second, site, standard, Standard_Deviation, station, statistics, suna, time, two, umol, university, water, water_depth, year";
    String keywords_vocabulary "GCMD Science Keywords";
    String license 
"The data may be used and redistributed for free but is not intended
for legal use, since it may contain inaccuracies. Neither the data
Contributor, ERD, NOAA, nor the United States Government, nor any
of their employees or contractors, makes any warranty, express or
implied, including warranties of merchantability and fitness for a
particular purpose, or assumes any legal liability for the accuracy,
completeness, or usefulness, of this information.";
    String neracoos_data_provider "UMO";
    Float64 Northernmost_Northing 43.491;
    String publisher_email "[email protected]";
    String publisher_name "Northeastern Regional Association of Coastal and Ocean Observing Systems (NERACOOS)";
    String publisher_phone "(603) 319-1785";
    String publisher_url "";
    String sourceUrl "(local files)";
    Float64 Southernmost_Northing 43.4907;
    String standard_name_vocabulary "CF Standard Name Table v29";
    String subsetVariables "Year, depth";
    String summary "Various nitrate sensors including the SUNA V1, SUNA V2 and ISUS (Sea-Bird Scientific) were deployed on NERACOOS Buoy M (Latitude: 43° 29.44'N and Longitude: 67° 52.79'W) from June 23, 2013 to March 23, 2021. This time period corresponds to University of Maine buoy deployments M0124, M0125, M0126, M0127, M0129, and M130 ( These sensors were placed at the surface, 1m, 50m, 100m, 150m and 250m and programmed to collect nitrate measurements six times per day (0045, 0445, 0845, 1245, 1645 and 2045 GMT) over a fixed sampling window of 30 seconds at approximately 1.4 readings per second. The number of sensors and their depths varied for each deployment depending on the number of available sensors. Five measurements recorded in the middle of the 30 second data stream were transmitted back to the University of Maine Physical Oceanography Group via cell phone. The mean concentration and standard deviation were calculated for each specific sampling time. If the standard deviation for a mean was greater than 2µM, the values were eliminated. Surviving data were then quality controlled (QCed) by removing outliers assessed as values less than -0.5µM and greater than 30µM.  Whenever possible at the time of buoy deployment and recovery, a standard CTD cast was conducted with a carousel water sampler equipped with Niskin bottles. Ground truth water samples were collected at the same depth as the nitrate sensors. These samples were analyzed for nitrate concentrations at the University of Maine using a Bran Luebbe AA3 Autoanalyzer and standard techniques. Ground truth corrections were added or subtracted as an offset only if the difference between the nitrate concentration of the water sample collected and the mean nitrate sensor reading at approximately the same time was greater than 2 µM. Upon recovery of the instruments, the data was processed using the software provided by Sea-Bird ( and compared with the real-time measurements as a check for accuracy. In the event that the sensor was not able to transmit in real-time, the processed data was QCed. Please contact David Townsend, [email protected], University of Maine, School of Marine Sciences if you have any questions.";
    String testOutOfDate "now-121days";
    String time_coverage_end "2021-03-24T00:45:00Z";
    String time_coverage_start "2013-06-23T16:45:00Z";
    String title "M01 SUNA - Nitrate Observations Corrected";
    Float64 Westernmost_Easting -67.88;


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The URL specifies what you want: the dataset, a description of the graph or the subset of the data, and the file type for the response.

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