{"id":203,"date":"2014-04-09T17:12:51","date_gmt":"2014-04-09T23:12:51","guid":{"rendered":"https:\/\/inside.nssl.noaa.gov\/wdssii\/?p=203"},"modified":"2017-01-23T11:59:54","modified_gmt":"2017-01-23T17:59:54","slug":"creating-rotation-tracks-using-wdss-ii","status":"publish","type":"post","link":"https:\/\/inside.nssl.noaa.gov\/wdssii\/2014\/04\/creating-rotation-tracks-using-wdss-ii\/","title":{"rendered":"Creating Rotation Tracks using WDSS-II"},"content":{"rendered":"

How do you go about creating rotation tracks starting from Level-II radar data from NCDC?<\/p>\n

\"w2image-KBMX_RotationTrack120min-20110428-030101-1\"<\/a><\/p>\n

The entire process is described in M. Miller, V. Lakshmanan, and T. Smith, “An automated method for depicting mesocyclone paths and intensities,” Wea. Forecasting, vol. 28, pp. 570-585, 2013<\/strong><\/p>\n

If you use Rotation Tracks in your research, please cite the above paper and also cite the papers for each of the following steps.<\/p>\n

    \n
  1. Untar the Level-II data and place it somewhere. Let’s call this directory RAWDIR<\/li>\n
  2. Get terrain netcdf data for your radar. You can get terrain files for US radars from ftp:\/\/ftp.nssl.noaa.gov\/users\/lakshman\/conus_radar_blockage.tgz.\u00a0\u00a0 Untar this, and let’s call this directory TERRAIN<\/li>\n
  3. Decide where you want your output products to go. Let’s call this DATADIR.<\/li>\n
  4. Define a variable RADAR to hold your radar identifier (e.g. KBMX)<\/li>\n
  5. Run ldm2netcdf to convert the Level-II data into NetCDF<\/li>\n
  6. QC the radar reflectivity data.\u00a0 Note that I am assuming that you have don’t have dualpol (if you do have dualpol, you should w2qcnndp) and that you do have super-resolution (if you have 1km resolution, change -R accordingly)<\/li>\n
  7. Dealias the velocity data<\/li>\n
  8. Compute Azimuthal Shear<\/li>\n
  9. Run w2merger to put the data on a LatLonGrid<\/li>\n
  10. Run w2accumulator with QC to create the rotation tracks<\/li>\n<\/ol>\n

    Here’s a script that will carry out the entire process. Edit as needed.<\/p>\n

    #!\/bin\/sh\r\n\r\nRAWDIR=`pwd`\/raw\r\nRADAR=KBMX\r\n\r\n# Overall reference about the entire process\r\n# M. Miller, V. Lakshmanan, and T. Smith, ``An automated method for depicting mesocyclone paths and intensities,'' Wea. Forecasting, vol. 28, pp. 570-585, 2013. \r\n\r\nTERRAIN=~\/WDSS2\/gtopo30\/radars\/$RADAR.nc\r\nDATADIR=`pwd`\/$RADAR\r\n\r\n# (5) convert Level-II to netcdf\r\n# V. Lakshmanan, T. Smith, G. J. Stumpf, and K. Hondl, ``The warning decision support system - integrated information,'' Wea. Forecasting, vol. 22, no. 3, pp. 596-612, 2007.\r\nldm2netcdf -i $RAWDIR -o $DATADIR -s $RADAR -p $RADAR -a -1 --verbose\r\nreplaceIndex -i $DATADIR\/code_index.fam -o $DATADIR\/code_index.xml\r\n\r\n# (6) note: if you have dualpol data, use w2qcnndp instead of w2qccn. The rest of the command-line is the same\r\n# V. Lakshmanan, A. Fritz, T. Smith, K. Hondl, and G. J. Stumpf, ``An automated technique to quality control radar reflectivity data,'' J. Applied Meteorology, vol. 46, pp. 288-305, Mar 2007\r\n# V. Lakshmanan, C. Karstens, J. Krause, and L. Tang, ``Quality control of weather radar data using polarimetric variables,'' J. Atm. Ocea. Tech., vol. 0, p. 0, 2013. \r\nw2qcnn -i $DATADIR\/code_index.xml -o $DATADIR -R 0.25x0.5x460 -s $RADAR -E $TERRAIN -u --verbose\r\nreplaceIndex -i $DATADIR\/code_index.fam -o $DATADIR\/code_index.xml\r\n\r\n# (7) note: if you have sounding information, provide it. the results will be better\r\n# Jing and Wiener 1993\r\ndealias2d -i $DATADIR\/code_index.xml -o $DATADIR --verbose\r\nreplaceIndex -i $DATADIR\/code_index.fam -o $DATADIR\/code_index.xml\r\n\r\n# (8) run LLSD\r\n# Smith and Elmore 2004 \r\nw2circ -i $DATADIR\/code_index.xml -o $DATADIR -a -w -z ReflectivityQC -Z 20 -D -t -c -L \"0:2:1.0:7.5:AGL\u00a0 3:6:0:90:AGL\" -V \"0.5 250 920\" -G $RADAR -g $TERRAIN --verbose\r\nreplaceIndex -i $DATADIR\/code_index.fam -o $DATADIR\/code_index.xml\r\n\r\n# (9) run w2merger to put the data on a cartesian grid\r\n# V. Lakshmanan, T. Smith, K. Hondl, G. J. Stumpf, and A. Witt, ``A real-time, three dimensional, rapidly updating, heterogeneous radar merger technique for reflectivity, velocity and derived products,'' Wea. Forecasting, vol. 21, no. 5, pp. 802-823, 2006. \r\n# V. Lakshmanan and T. W. Humphrey, ``A MapReduce technique to mosaic continental-scale weather radar data in real-time,'' IEEE J. of Select Topics in Appl. Earth Obs. and Remote Sensing, vol. 0, no. 0, 2013.\r\nTOP=`grep -A 2 $RADAR ~\/WDSS2\/src\/w2\/w2config\/misc\/radarinfo.xml | head -2 | tail -1 | sed 's\/[=\\\"]\/ \/g' | awk '{print $3+4,$5-4}'`\r\nBOT=`grep -A 2 $RADAR ~\/WDSS2\/src\/w2\/w2config\/misc\/radarinfo.xml | head -2 | tail -1 | sed 's\/[=\\\"]\/ \/g' | awk '{print $3-4,$5+4}'`\r\necho \"$TOP to $BOT\"\r\nw2merger -i $DATADIR\/code_index.xml -o $DATADIR -I AzShear_0-2kmAGL -p 0.001 -e 60 -C 1 -R 230 -t \"$TOP 1\" -b \"$BOT 0\" -s \"0.005 0.005 1\" --verbose\r\nreplaceIndex -i $DATADIR\/code_index.fam -o $DATADIR\/code_index.xml\r\n\r\n# (10) run w2accumulator with QC\r\n# V. Lakshmanan, M. Miller, and T. Smith, ``Quality control of accumulated fields by applying spatial and temporal constraints,'' J. Atmos. Ocean. Tech., vol. 30, pp. 745-757, 2013. \r\nw2accumulator -i $DATADIR\/code_index.xml -o $DATADIR -R -s -t \"60 120 360\" -C 1 -O RotationTrack -t 120 -Q blob:0.002:0.005:25:azshear,mht:1:2:1800:5:1 -g MergedAzShear_0-2kmAGL --verbose\r\nreplaceIndex -i $DATADIR\/code_index.fam -o $DATADIR\/code_index.xml<\/pre>\n","protected":false},"excerpt":{"rendered":"
    How do you go about creating rotation tracks starting from Level-II radar data from NCDC? The entire process is described in M. Miller, V. Lakshmanan, and T. Smith, “An automated… <\/p>\n
    Read more \u00bb<\/a><\/p>\n","protected":false},"author":32,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-203","post","type-post","status-publish","format-standard","hentry","category-news"],"_links":{"self":[{"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/posts\/203","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/users\/32"}],"replies":[{"embeddable":true,"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/comments?post=203"}],"version-history":[{"count":3,"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/posts\/203\/revisions"}],"predecessor-version":[{"id":208,"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/posts\/203\/revisions\/208"}],"wp:attachment":[{"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/media?parent=203"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/categories?post=203"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/inside.nssl.noaa.gov\/wdssii\/wp-json\/wp\/v2\/tags?post=203"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}