MET Version 3.1

Release Date:

The MET Version 3.1 was released on February 7, 2012.

Release Notes

What's New?

The majority of the changes for METv3.1 are internal restructuring and streamlining of how MET reads gridded data, which should be transparent to the user. However, there have been several enhancements the typical user may notice. Please refer to the MET User's Guide for more detail on these additions:


Major Upgrades

  • Implemented a new data class hierarchy for reading gridded data files to enable future support of additional data formats, such as GRIB2.
  • Incorporated a new logger class throughout MET causing all messages printed to the screen to be prefixed with a message type of ERRORWARNING, or DEBUG(N), where N indicates the debug level (default is 2):
    • 0: Suppress all messages except WARNING and ERROR.
    • 1: List input and output files.
    • 2: List summary processing information.
    • 3: List detailed processing information.
    • 4+: List detailed debugging information.
  • Added a -log command line option to all the MET tools to optionally write their output to a log file.
  • Changed how MET is storing gridded data from using an integer scale and offset to a double. The integer scale and offset approach used in prior versions of MET caused individual gridded data values to be stored using only five significant digits.
    • Comparing previous versions to METv3.1, users should notice only slight differences in the continuous statistics MET produces (CNTand SL1L2 line types).
    • However, users may notice more significant differences in statistics that are based on defining a threshold. Due to these precision issues, the contingency tables counts and statistics (CTC and CTSline types) MET produces may change significantly in METv3.1.
    • METv3.1 has enhanced precision over earlier versions and more accurately represents the input data and resulting statistical measures.

New Tools

  • Added new madis2nc tool to reformat MADIS NetCDF point observation files into a NetCDF format that MET can read. Currently supports METAR and RAOB types of MADIS files with additional MADIS data types to be added in future releases.
  • Added new plot_data_plane utility to read any supported gridded data file, select a field from that file, and render it as a PostScript image.

Enhancements to Existing Tools

  • Distributed latest set of bug fixes for METv3.0.1.
  • Changed the default output directory for the MET statistics tools from MET_BASE/out/tool_name to the current directory.
  • Enhanced plot_point_obs by adding a -data_file command line argument to specify the grid on which the points should be plotted. Included detailed DEBUG(4) information about the points being plotted.
  • Enhanced stat_analysis to enable job command arguments on the command line to be used in conjunction with a configuration file. Included detailed DEBUG(4) information when deriving wind directions.
  • Enhanced wwmca_regrid and wwmca_plot to specify the pixel age when processing the data.
  • Enhanced mode to perform the convolution step more quickly.
  • When using MET statistics tools (like grid_statpoint_statwavelet_statensemble_stat, and mode) to verify the NetCDF output of other MET tools (like pcp_combine and ensemble_stat), added logic to look for the name and level NetCDF variable attributes. If present, write those values out into the FCST_VAROBS_VARFCST_LEV or OBS_LEV statistical output columns.
  • In the mode_analysis -summary job, modified the computation of the standard deviations by dividing by N-1 rather than N which will have a slight impact on the output.

Enhancement to the Build Process

  • Modified the configuration and build process for MET by grouping the parameters that the user needs to edit into a file named in the top-level MET directory.
  • Reorganized the MET directory structure to use srcinclude, and lib sub-directories for the source code, headers, and compiled libraries, respectively.

Known Issues and Fixes

All Recommended Updates (Last Updated 05/01/2012)

Retrieve all of the recommended updates for METv3.1 in a tarfile:

  • Download the tarfile METv3.1_patches_20120501.tar.gz
  • Copy it into the top-level METv3.1 directory.
  • Uncompress and untar the file. Please note that the new version of the files in the tarball will overwrite the original version of those files. Any changes you may have made will be lost.
  • Rebuild MET, being sure perform a make clean first.

Summary of Recommended Updates

  • 02/10/2012: Fix for reading both user-generated and METv2.0 and prior gridded NetCDF files.
  • 03/01/2012: Fix in pcp_combine for finding records to operate on.
  • 03/05/2012: Fix in point_stat for parsing the -obs_valid_end command line option.
  • 03/07/2012: Fix for timing information for the pcp_combine -add and -subtract options.
  • 03/29/2012: Fix in pcp_combine for -add command to correct accumulated output.
  • 05/01/2012: Fix in ensemble_stat for gridded observations not in GRIB1 format.

MET Libraries

Problem reading both user-generated and METv2.0 and prior gridded NetCDF files.
Posted 02/10/2012

Problem: When trying to read gridded NetCDF files that are either user-generated or from earlier versions of MET, it is erroring out with:
unsupported gridded data file type "4"
Solution: The fix is modifying the gridded data file type logic.
Update: METv3.1/src/libcode/vx_data2d_factory/
And then recompile MET.

MET Applications

Problem in pcp_combine finding user-specified records to operate on.
Posted 03/01/2012

Problem: When running pcp_combine, the utility would error out reporting that it could not find the data_plane with an error message that depended on the input file type.
Solution:Several uninitialized variables were found to be the cause, and they were set to 0.
Update: METv3.1/src/tools/core/pcp_combine/
And then recompile MET.

Problem in point_stat when parsing the -obs_valid_end command line option.
Posted 03/05/2012

Problem: When parsing the -obs_valid_end command line option, point_stat was calling the wrong function to parse it's value.
Solution: This is a one line fix to call the correct parsing function.
Update: METv3.1/src/tools/core/point_stat/
And then recompile MET.

Problem with timing information for the pcp_combine -add and -subtract options.
Posted 03/07/2012

Problem: When using the pcp_combine -add and -subtract options, the timing information was not being handled properly, leading to erroneous times in the output NetCDF files.
Solution: The fix involves updates to the get_field() function within
Update: METv3.1/src/tools/core/pcp_combine/
And then recompile MET.

Problem in pcp_combine -add functionality that caused accumulated output to be all bad data values.
Posted 03/29/2012

Problem:When using the pcp_combine -add functionality, no matter what the input data contained, the accumulated output was always a constant field of bad data values (-9999). 
Solution: Fixed an initialization problem for the field of accumulated values.
Update: METv3.1/src/tools/core/pcp_combine/
And then recompile MET.

Problem in ensemble_stat when verifying against gridded observations that are not in GRIB1 format.
Posted 05/01/2012

Problem: Ensemble-Stat was trying to parse the obs_field configuration setting as GRIB1 information regardless of the type of gridded data file passed to it.
Solution: The fix is update logic in the vx_statistics library to enable the Ensemble-Stat to handle all the gridded data file types.
Update: METv3.1/src/tools/core/ensemble_stat/
Update: METv3.1/src/libcode/vx_statistics/pair_data_ensemble.h
Update: METv3.1/src/libcode/vx_statistics/
And then recompile MET.