Data Access Form

Dataset Title:	Currents, HF Radar, US West Coast, Near-Real Time, 6km
Dataset ID:	ndbcHfrW6
Institution:	NOAA NDBC
Information:	Summary \| Variables \| Background \| Make A Graph

Dimensions	First	Size	Spacing	Last
time (UTC)	2009-02-14T19:00:00Z	66	01:00:00 (even)	2009-02-17T12:00:00Z
latitude (degrees_north)	30.25	367	0.05394 (even)	49.99204
longitude (degrees_east)	-130.36	234	0.06246524 (even)	-115.8056
Grid Variables (which always also download all of the dimension variables)
u (Surface Eastward Sea Water Velocity, m s-1)
v (Surface Northward Sea Water Velocity, m s-1)
DOPx (Longitudinal Dilution of Precision)
DOPy (Latitudinal Dilution of Precision)

File type:

The Dataset Attribute Structure (.das) for this Dataset

Attributes {
  time {
    String _CoordinateAxisType "Time";
    Float64 actual_range 1.234638e+9, 1.234872e+9;
    String axis "T";
    String calendar "gregorian";
    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";
  }
  latitude {
    String _CoordinateAxisType "Lat";
    Float32 actual_range 30.25, 49.99204;
    String axis "Y";
    String ioos_category "Location";
    String long_name "Latitude";
    String standard_name "latitude";
    String units "degrees_north";
  }
  longitude {
    String _CoordinateAxisType "Lon";
    Float32 actual_range -130.36, -115.8056;
    String axis "X";
    String ioos_category "Location";
    String long_name "Longitude";
    String standard_name "longitude";
    String units "degrees_east";
  }
  u {
    String ancillary_variables "DOPx";
    Float64 colorBarMaximum 0.5;
    Float64 colorBarMinimum -0.5;
    String ioos_category "Currents";
    String long_name "Surface Eastward Sea Water Velocity";
    String standard_name "surface_eastward_sea_water_velocity";
    String units "m s-1";
  }
  v {
    String ancillary_variables "DOPy";
    Float64 colorBarMaximum 0.5;
    Float64 colorBarMinimum -0.5;
    String ioos_category "Currents";
    String long_name "Surface Northward Sea Water Velocity";
    String standard_name "surface_northward_sea_water_velocity";
    String units "m s-1";
  }
  DOPx {
    Float64 colorBarMaximum 1.0;
    Float64 colorBarMinimum 0.0;
    String colorBarPalette "WhiteRedBlack";
    String comment 
"The longitudinal dilution of precision (DOPx) represents the
contribution of the radars' configuration geometry to
uncertainty in the eastward velocity estimate (u). DOPx is a
direct multiplier of the standard error in obtaining the
standard deviation for the eastward velocity estimate from the
least squares best fit. DOPx and DOPy are commonly used to
obtain the geometric dilution of precision
(GDOP = sqrt(DOPx^2 + DOPy^2)), a useful metric for filtering
errant velocities due to poor geometry.";
    String ioos_category "Currents";
    String long_name "Longitudinal Dilution of Precision";
  }
  DOPy {
    Float64 colorBarMaximum 1.0;
    Float64 colorBarMinimum 0.0;
    String colorBarPalette "WhiteRedBlack";
    String comment 
"The latitudinal dilution of precision (DOPy) represents the
contribution of the radars' configuration geometry to
uncertainty in the northward velocity estimate (v). DOPy is a
direct multiplier of the standard error in obtaining the
standard deviation for the northward velocity estimate from the
least squares best fit. DOPx and DOPy are commonly used to
obtain the geometric dilution of precision
(GDOP = sqrt(DOPx^2 + DOPy^2)), a useful metric for filtering
errant velocities due to poor geometry.";
    String ioos_category "Currents";
    String long_name "Latitudinal Dilution of Precision";
  }
  NC_GLOBAL {
    String cdm_data_type "Grid";
    String Conventions "CF-1.1";
    String format_version "HFRNet_1.0.0";
    Float32 geospatial_lat_max 49.99204;
    Float32 geospatial_lat_min 30.25;
    Float32 geospatial_lon_max -115.805565;
    Float32 geospatial_lon_min -130.36;
    String grid_projection "equidistant cylindrical";
    String history 
"17-Feb-2009 00:28:29:  NetCDF file created
2009-02-17 http://sdf.ndbc.noaa.gov/thredds/dodsC/hfradar_uswc_6km
2009-02-17 http://coastwatch.pfeg.noaa.gov/erddap/griddap/ndbcHfrW6.html";
    String infoUrl "http://sdf.ndbc.noaa.gov/thredds/catalog.html?dataset=hfradar_uswc_6km";
    String institution "NOAA NDBC";
    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 netcdf_library_version "netcdf library version 3.6.1 of Jul 17 2008 22:03:01 $";
    String product_version "HFRNet_1.1.03";
    String references 
"Terrill, E. et al., 2006. Data Management and Real-time
Distribution in the HF-Radar National Network. Proceedings
of the MTS/IEEE Oceans 2006 Conference, Boston MA,
September 2006.";
    String source "Surface Ocean HF-Radar";
    String sourceUrl "http://sdf.ndbc.noaa.gov/thredds/dodsC/hfradar_uswc_6km";
    String standard_name_vocabulary "CF-1.0";
    String summary 
"Surface ocean velocities estimated from HF-Radar are
representitive of the upper 0.3 - 2.5 meters of the
ocean.  The main objective of near-real time
processing is to produce the best product from
available data at the time of processing.  Radial
velocity measurements are obtained from individual
radar sites through the HF-Radar Network and
processed to create near-real time velocities
(RTVs)";
    String title "Currents, HF Radar, US West Coast, Near-Real Time, 6km";
  }
}

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