readADCP_mod

Description

readADCP_mod is a utility for reading and processing RDI ASCII ADCP (Acoustic Doppler Current Profiler) files. It serves a similar purpose to readADCP and readADCP_g, converting raw ADCP data into a time-series profile saved as a JHC-formatted image file (.prof).

This version allows for the visualization of velocity magnitude, azimuth, or backscatter. It supports georeferencing via an external navigation file and can stack (average) data over a set number of ensembles or within geographic bins on a map. The _mod suffix suggests it is a modified version, likely with a feature set that is a subset of the main readADCP tool.

Usage

readADCP_mod -in <infiles> -out <outfile> [OPTIONS]

Key Options

Option Description
-in <infilename(s)> Required. One or more input RDI ASCII ADCP files.
-out <outfile> Required. The prefix for the output filenames.
-nav <navfile> Use an external OMG-HDCS navigation file for positioning.
-use_adcp_nav Use the navigation data embedded within the ADCP files.
-map <mapfile.map> Georeference and stack the output profiles onto a map grid.
-pixel <size> The horizontal pixel size for the output map, if -map is used.
-mindepth <m> / -maxdepth <m> Set the minimum and maximum depth range to process.
-bottom_ref Reference depth layers relative to the seafloor instead of the sea surface.
-layers <num> Set the number of vertical bins in the output profile. Default is 100.
-draft <m> Specify the draft of the ADCP transducer to correct the depth values.
-showMAG (Default) Display velocity magnitude in the output profile.
-showBS Display backscatter intensity. Use with -BSrange.
-showAZI Display velocity direction (azimuth).
-maxcurrent <m/s> Set the maximum current for scaling the output image colors (for magnitude display).
-BSrange <min> <max> Set the min/max backscatter values for color scaling.
-ensem_stack <num> Average (stack) data over a specified number of ensembles.
-stack_in_map When using -map, creates a single, averaged profile for all data falling within the map area.
-headbias <deg> Apply a constant heading correction in degrees.
-delay <sec> Apply a time delay in seconds to the data.
-tidefile <tide.nav> Use an external navigation file to provide tidal height corrections.
-phase_zero <Y J H M> Defines the reference start time for tidal phase calculations.
-v Enable verbose output.
-min_vels_to_av <num> Minimum number of depth-averaged velocities required to write an output nav record.

How It Works

  1. Read Data: The tool reads ADCP data from the specified input files.
  2. Georeferencing: It uses either an external (-nav) or internal (-use_adcp_nav) source for geographic positioning.
  3. Data Extraction: It processes each ADCP ensemble and extracts the user-selected data type (Magnitude, Azimuth, or Backscatter) for each depth bin.
  4. Profile Generation: The vertical data for each ensemble is binned into a profile. The depth axis can be referenced to the sea surface or the seafloor (-bottom_ref).
  5. Output: The generated profile is written as a column to the output .prof image file, creating a time-series visualization.
  6. Stacking/Mapping: If the -ensem_stack or -map options are used, the tool performs averaging either over time or space before writing the final output.