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The Advanced Dvorak Technique (ADT) algorithm is a computer-based technique, developed at the University of Wisconsin-Madison/Cooperative Institute for.
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(McIDAS Version 8.2.1)
Prepared by
Timothy L. Olander and Christopher S. Velden
On behalf of
The Cooperative Institute for Meteorological Satellite Studies Space Science and Engineering Center University of Wisconsin-Madison 1225 West Dayton Street Madison, WI 53706
February 2015
about HURSAT data). Finally, the utilization of an internal image navigation/calibration code package, distributed with previous versions of the ADT, has been eliminated and replaced with use of the McIDAS navigation/calibration core routines. This modification is the primary impetus for the use of HURSAT data when the ADT is compiled outside of the McIDAS environment (HURSAT data is internally navigated and calibrated).
For greater detail about the development process and statistical accuracy obtained with the current and previous ODT/ADT algorithm, please refer to Velden et al. (1998), Olander et al. (2004, 2002), Olander and Velden (2007), the ADT homepage (http://tropic.ssec.wisc.edu/misc/adt/info.html), or various conference presentations and/or proceedings.
The ADT was originally developed within the Man computer Interactive Data Access System (McIDAS) architecture. The algorithm utilizes McIDAS library functions and routines to ingest infrared satellite data, display textual and graphical results, read various input data files, and write various output files. The ADT has been tested and operated on a wide variety of UNIX/LINUX operating systems. Use of either the GCC C-compiler or GFORTRAN FORTRAN-compiler (depending on how the local McIDAS was compiled) is recommended.
The scripts and programs contained within the ADT software package to access and read the PMW data files are defined for specific data sets which are formatted in HDF. A tar file for HDF4 library has been included with this distribution in the ADTV8.2.1/PMW/PreformatHDFfiles directory. A README file in the ADTV8.2. directory describes how to install and utilize this library. The PMW data can be utilized within the McIDAS environment or when the ADT is compiled in non-McIDAS mode.
If the ADT is to be compiled in the “Non-McIDAS” mode, the netCDF library (and all dependency libraries) must be installed on the local system to allow for the utilization of HURSAT netCDF data. This will require that the local system contains the netCDF version 4.0 with HDF4/5 capability.
The ADT code libraries can be ported into various systems utilizing the various API (application programming interface) routines provided within the tar file (as described in Section 6 below). Non-McIDAS systems can replace the McIDAS-specific functions with their own system functions to access the satellite imagery and provide their own graphical user interface (GUI) to replace the McIDAS command line and image display interface.
Prior to installation of the ADT for use within the McIDAS, the current libmcidas.a library file must be located and linked to within the lib directory. The ADT requires this file for all text and graphical output within the McIDAS user interface windows as well as for all satellite navigation and calibration routines. The use of the McIDAS nav/cal routines replaces the included nav/cal routines provided in older ADT versions, making compiling a bit easier and allowing for more frequent and accurate updates of the navigation and calibration routines as new satellites are launched and made operational. The libmcidas.a file should reside in the ~mcidas/lib directory.
The actual linking is performed within the “compileall” script using the variable MCLIB to define the location of the libmcidas.a file. The MCLIB variable should be modified in this script to reflect its location on the machine where the ADT is being installed. Note the entire path name must be used instead of the “~mcidas/lib” designation (e.g. /home/mcidas/lib). Once the MCLIB variable has been defined, the ADT algorithm can be compiled using the “compileall” script file using the following command (to assure that the ADT is compiles with all necessary McIDAS dependencies):
compileall mcidas
Please refer to Section 5P for information about compiling and using the ADT outside of the McIDAS environment.
As mentioned previously, the ADT software package has changed significantly with the release of Version 8.2.1 over previous public released versions. The inclusion of in-line passive microwave (PMW) eye score derivation to augment the intensity estimation process has improved the accuracy of the ADT but complicated the installation and compile process. A README file has been included in the top level directory to help guide the user through the necessary modifications to ensure that the ADT is installed/compiled correctly.
The test directory contains scripts and data to allow the user to check the installation of the ADT on the local platform with results obtained at CIMSS. The README file within the test directory contains important information relevant to installing and running this test scripts and comparing the output with those obtained by CIMSS scientists.
The ADT algorithm operates within the McIDAS architecture, utilizing the McIDAS text and graphics/image windows for command line input, data access, and image analysis. Runtime status and final analysis text output are displayed within the McIDAS text window, with image display and graphical output displayed within the McIDAS graphics/image window.
Use of the ADT algorithm is initiated via the McIDAS command line structure using a selection of keywords to control various functions of the ADT algorithm. All ADT keywords are defined in Section 4A1, with examples provided in Section 4A3.
A.) Command Line Structure and Keywords
The ADT is initiated and controlled with the following command line structure:
ADT
Various input parameters control different aspects of the ADT algorithm, many of which can be used in combination with specific keywords to perform particular tasks. A short description of use for each parameter and keyword, along with several examples, will be presented in the following sections.
1.) Description of Use
ADT -- Advance Dvorak Technique ADT
Parameters: AUTO Allows for automated ADT estimate to objectively determine position of storm center (see Section 5.J.2) DEL Deletes history file record; Must be used with DATE= keyword to define date/time limits EDIT Allow user to add or modify a comment to history file record(s). An important note regarding the use of the EDIT parameter when utilizing the MW keyword and/or PMW data information is in the Remarks section. LIST Lists contents of history file (see Remarks)
CKZ=YES gale_radius pressure_env Utilize Coutney/Knaff/Zehr wind speed/pressure derivation technique to determine mean sea level pressure estimate value. Must input 34-knot wind/gale radius value (in nmi) and environmental pressure value (in mb). If 34-knot wind/gale radius is not available, the radius of last closed isobar (in nmi) can be used but value must be multiplied by -1. (def=NO)
COLor=CI MSLP FinalT Adj-RawT UnAdj-RawT outline text Defines graphic color levels of plotted parameters (def=1 2 0 0 0 6 7; 0 to not display)
DATe=beg_day beg_time end_day end_time Defines range of dates and times for LIST, PLOT and DEL options; can be any valid McIDAS date/time format or ADT date format yyyy/mm/dd, yyyy-mm-dd, dd/mon/yyyy, dd-mon-yyyy, yyyymondd yyyy=year, dd=date (1-31) mm=integer month (1-12), mon=character month (min 3 characters)
DATAset=src_dataset local_dataset
DOMain=ATL/PAC Defines domain for CI to MSLP conversion; valid options: ATL or PAC, see Remarks (def=computed)
Applies ADT land interaction rule (def=YES)
MW=flag/file YES/NO (or OLD score date time) Passive Microwave (PMW) eye information input. See Section 5.N for more details on this process. Flag/File value containing a file name will direct ADT to derive eye score value directly from input microwave data file. If an input file is entered, entering a value of “YES” for the second
variable will output ASCII files which can be used in the graphical display production process using scripts in the plotPMWscore directory (def=NO). Format of this input file can be found in Section 4F1. Flag/File value of “OLD” will allow for old method of direct entry of PMW eye score along with overpass date and time (in the second, third, and fourth variable input values). Date must be in YYYYmonDD format (YYYY=year, mon=three letter ID for month, DD-day), time is in HHMMSS format. (def=X, meaning no PMW analysis). See Remarks section below for more information on how to obtain information when using “OLD” keyword. Also see the Remarks section for an important note on a known bug when utilizing PMW information.
MAXWradius=value Manually defines maximum wind radius (in km). If the ADT estimate has determined an eye scene and the MAXW of less than 5 km is specified, the scene type will be changed to PINHOLE EYE. If a value of MAXW of greater than or equal to 38 km is specified, the scene type will be changed to LARGE EYE (no default).
NETCDF=YES filename Allows a user to define the netCDF HURSAT-format data file when the ADT is compiled and executed in non-McIDAS mode. The directory location of the file is defined using the ODTDATA environmental variable. (def=NO)
OUTput=loc filename Defines location of LIST option output; valid option T, FILE or TFILE, where T, sends the LIST output to the current text window, FILE, sends the output to a file (def=ODTDUMP.ASC) where the directory is defined by the environmental variable ODTOUTPUT or TFILE, where the output is sent to both the window and a file (def=T)
OVERride=YES Allows a user to interactively override the automated scene type; cannot be used with AUTO option (def=NO)
RMW=value Manual input value for radius of maximum wind distance (in km). Value is used in order to override automated RMW determination technique and aid in pinhole eye determination (no default). Positive value will indicate usage of value.
RAWT=init_rawt Allows a user to override the initial raw T intensity value as defined by the subjective Dvorak rules; see Remarks (def=1.0)
active storm. Refer to http://tropic.ssec.wisc.edu/real-timeadt/adt.html for a list of current active storms. Click on the storm of interest, then on the “PMW Information” link to access the PMW overpass date, time, and eye score information.
IMPORTANT NOTE A known bug currently exists either when the EDIT parameter is used or a new record is inserted (not at the end) within an existing history file and PMW data information is stored in the history file. If a record(s) is/are inserted/modified/deleted from the ADT history file, the PMW data information for all history file entries following the modified record(s) will be incorrectly modified. It is STRONGLY recommended at this time to NOT UTILIZE the EDIT parameter to modify/delete records within a history file. Also it is recommended TO NOT INSERT an ADT analysis anywhere but at the end of an existing ADT history file since the PMW information within the history file for any subsequent records may/will be improperly modified. A fix for this bug is currently being worked on at this time.
2.) Examples
ADT Perform abbreviated ADT analysis on current image. Only the current Raw T# will be displayed, with no time averaging or application of any being performed. Output will not be written to any history file. ADT OPAL.ODT Perform ADT analysis and add record to history file OPAL.ODT. All rules will be applied as necessary. If this is the first analysis in the OPAL.ODT history file, the initial Raw T# value classification will be set to 1.0. ADT OPAL.ODT RAWT=2. Perform ADT analysis on the first record within the OPAL.ODT history file, however the initial intensity estimate (first record in history file) within the history file will be set to 2.5. ADT OPAL.ODT ATCF=13L NHC 0 1 Perform ADT analysis and add record to history file OPAL.ODT. All rules will be applied as necessary. Output file containing intensity estimate for current analysis in ATCF format will be created with annual tropical cyclone ID of 13L, Fix Center of NHC, Adjusted Raw T# value, and 3-hour linear averaged Final T# value displayed. ADT OPAL.ODT OVER=YES Perform ADT analysis and add record to history file OPAL.ODT. User will be presented with the evaluated ADT Scene Type and prompted to accept or change this value. ADT PLOT OPAL.ODT COLOR=3 4 5 1 2 X X Display graph of contents of history file OPAL.ODT in current graphic image using color level 3, 4, 5, 1, and 2 for the CI#, Adjusted MSLP, Final T#, Adjusted Raw T#, and Unadjusted Raw T# plots, respectively. Graph boundary and wording will utilize the default values. No intensity analysis is performed.
ADT LIST OPAL.ODT List contents of history file OPAL.ODT within McIDAS text window. No intensity analysis is performed. ADT LIST OPAL.ODT ATCF=13L NHC 0 1 List contents of history file OPAL.ODT within McIDAS text window in ATCF format. No intensity analysis is performed ADT LIST OPAL.ODT OUTPUT=FILE OPAL.TXT Do NOT perform ADT analysis; provide listing of history file OPAL.ODT to output file OPAL.TXT within directory defined with the ODTOUTPUT environment argument. ADT DEL OPAL DATE=1995/10/03 151500 Delete only the 3 October 1995 at 15:15:00UTC record from the history file OPAL.ODT. No intensity analysis is performed, but all subsequent records in the history file are modified following the deleted record. ADT DEL OPAL DATE=03/OCT/1995 15:15:00 03/MAR/1995 19:15: Delete all records between 3 October 1995 at 15:15:00UTC and 3 October 1995 at 19:15:00UTC from the history file OPAL.ODT, inclusive. No intensity analysis is performed, but all subsequent records in the history file are modified following the deleted records. ADT LIST HISTORY=OPAL DATE=03-Oct-1995 1500 List all records between 3 October 1995 at 00:15:00UTC and the end of the history file OPAL.ODT. No intensity analysis is performed. ADT LIST OPAL DATE=X X 1995OCT03 3:15: List all records between the beginning of the history file OPAL.ODT and 3 October 1995 at 3:15:00UTC. No intensity analysis is performed. ADT AUTO PACWARN wp2698.txt 26W1998.ODT Perform automated ADT analysis and add record to history file 26W1998.ODT. ADT will read JTWC Tropical Cyclone Warning file wp2698.txt for forecast information, and is located in the directory defined by the ODTAUTO environment argument. ADT OPAL.ODT DATASET=EASTS/NH.-1 ALL. Perform manual ADT analysis on the second most recent image position in the ADDE remote dataset server group EASTS/NH. A subset of the displayed image will be copied to the ADDE local dataset server group (alias) ALL in the 9990 position. See Sections 4C and 4D6 for more details. ADT OPAL.ODT CKZ=YES 85 1002 Perform manual ADT analysis utilizing the Courtney/Knaff/Zehr wind speed/pressure relationship to derive MSLP estimate using 85 nmi as the 34 knot wind/gale radius and 1002mb as the environmental pressure value. ADT OPAL.ODT CKZ=YES -180 1008 Perform manual ADT analysis utilizing the Courtney/Knaff/Zehr wind speed/pressure relationship to derive MSLP estimate using 1008 mb as the environmental pressure value and - 180 as the proxy value for the unavailable 34 knot wind/gale radius (radius of outer closed isobar = 180 nmi). ADT AUTO PACWARN wp26forecast.txt 26W.ODT MW=mwdata/latest/latest_26W YES Perform automated ADT analysis using PMW eye score analysis using JTWC Discussion file wp26forecast.txt and PMW image file latest_26W stored in
B.) History File
The ADT history file is an ASCII format file containing ADT intensity estimates, locations, and other specific information for each image analysis. The ADT algorithm utilizes records in the history file for the determination of the intensity estimate values as well as the application of various rules utilized within the intensity estimate routines. Each analysis stored in the history file will contain the following values:
Value 1 : date (YYYYMMMDD format : YYYY=year, MMM=month, DD=day) Value 2 : time (hhmmss format) Value 3 : Julian day and partial day Value 4 : raw T# unadjusted Value 5 : raw T# adjusted by Rule 8 rules Value 6 : final T# value (3-hour average) Value 7 : final CI# value Value 8 : eye region temperature (C) Value 9 : mean cloud region temperature (C) – movable annulus Value 10 : mean cloud region temperature (C) – set region (old method) Value 11 : “coldest-warmest” cloud region temperature (C) Value 12 : storm center latitude (+/- = North/South Hemisphere) Value 13 : storm center longitude (+/- = West/East Hemisphere) Value 14 : eye diameter, CDO size, or shear distance (in km) Value 15 : eye region temperature standard deviation value Value 16 : cloud region symmetry value Value 17 : satellite ID value Value 18 : eye region scene type (original value) Value 19 : cloud region scene type (original value) Value 20 : eye region scene type (original value if user override performed) Value 21 : cloud region scene type (original value if user override performed) Value 22 : Dvorak Weakening (Dvorak EIR Rule 9) flag Value 23 : Dvorak Constraint Limits (Dvorak EIR Rule 8) flag Value 24 : latitude bias application flag Value 25 : rapid dissipation flag (east pacific only) Value 26 : land/ocean flag Value 27 : eye region FFT value Value 28 : cloud region FFT value Value 29 : curved band analysis – BD curve gray scale value Value 30 : curved band analysis – convection curvature amount (out of 25) Value 31 : distance from center to “coldest-warmest” temperature value Value 32 : automated center determination flag Value 33 : MSLP latitude bias adjustment value Value 34 : radius of maximum wind (in km) Value 35 : input or derived passive microwave (PMW) “eye score” value Value 36 : PMW date (YYYYMMMDD format; see Value 1 above) Value 37 : PMW time (hhmmss format; see Value 2 above) Value 38 : input 34 knot wind/gale radius value for CKZ (in nmi) Value 39 : input environmental pressure value for CKZ (in mb) Value 40 : satellite viewing angle (in degrees) Value 41 : user comment – if available
History files should not be modified directly. Any modifications, such as reanalysis or removal of individual records, should only be done using the ADT
command line entry with select keywords, such as DELETE and DATE, in order to assure correct modification to the remaining history file entries.
C.) UNIX Environment Variables
In order to provide more control regarding various ADT input/output file and directory definitions, the ADT utilizes six UNIX environment variables to define specific definitions used within the ADT algorithm. This provides the user greater ability to personalize the ADT to the local machine on which it is operating. The variables are defined in the file “ adtenv ” located in the main ADT directory.
Variable Description ODTHOME Top level directory location for ADT code ODTAUTO Directory for forecast files for ADT auto mode ODTDATA Directory where local AREA files are stored ODTHISTORY Directory where ADT history files are stored ODTOUTPUT Directory for LIST/ATCF output ODTPMW Directory for PMW input and output files ODTTOPO Directory where TOPOHRES topography file is located ODTPMW Directory where PMW scripts/data are found
The default location for the base directory is defined using the $ODTHOME parameter, which is defined on line one of the adtenv file. The default location of this variable is the top directory of the ADT directory tree. If any of the variable names are not defined in the adtenv file explicitly, the value will default to the $HOME environment variable value.
The ODTDATA variable is the directory location where either the McIDAS AREA files or HURSAT netCDF files are stored on the local machine (e.g. $HOME/mcidas/data). This value will be used with the local_dataset value with the DATASET keyword to define where the downloaded image will be stored.
The ODTPMW variable is the top level directory where the PMW ingest and processing scripts and programs are located. Typically this will be the PMW subdirectory of the $ODTHOME parameter defined in the adtenv file (e.g. /home/user/ADTV8.2.1/PMW). All internal processing input and output definitions will utilize this $ODTPMW environmental variable.
To install these variables within the UNIX environment, use the following command on the UNIX command line:
. adtenv
Weakening Flag : OFF Rapid Dissipation Flag : OFF C/K/Z MSLP Estimate Inputs :
ADDED RECORD TO END OF HISTORY FILE /home/adt/ADTV8.2.1/history/23WMW.ODT WROTE 66 RECORDS TO HISTORY FILE /home/adt/ADTV8.2.1/history/23WMW.ODT Successfully completed ADT analysis
The first section of the ADT intensity bulletin output includes the runtime messages, which provide general information about the history file being used and various other parameters used in the derivation of the current intensity estimate. The history file utilized will be displayed first, and thus a full ADT analysis will be performed on the image. This will be indicated by the following message:
Performing full ADT analysis
The exact output displayed in the runtime messages will depend upon how the ADT is executed. The above example shows the output when using the ADT in automated mode; displaying the forecast file information, forecast interpolation status, and any automated storm center determination method output. If the PMW analysis functionality is utilized, additional runtime information from those related programs will be output prior to the autopositioning methodology output (see Section 4F).
The path and file name of the current image file being analyzed will be listed prior to the intensity estimate bulletin. In this example the locally stored image file is named AREA2010. The path to this image is defined by the $MCPATH environment variable, and is defined in the local “.mcenv” file. For an example of remotely stored data, and its corresponding output messages, see Section 4D6.
Within the intensity estimate bulletin, all vital information relating to the current image analysis will be displayed. The date, time, and location are presented first, followed by the four intensity estimate values; the current unadjusted Raw T#, adjusted Raw T#, Final T# (3-hour average), and CI#.
The “Raw T#” value is the unadjusted Raw “DT” number determined using the current scene type and measured environmental parameters (Section 5B and 5C) for the selected scene type (cloud curvature, eye/cloud temperatures, etc.). The “Adj T#” value represents the current intensity of the storm after any Constraint Limit (Dvorak “Rule 8”) rules have been applied (see Section 5F). The “Final T#” value is the average of the current and previous three hour analyses values (see Section 5D). Finally, the “CI#” value represents the 3-hour averaged value after various ADT rules and constraints governing its variability, listed next to the Constraint Limits and Weakening Flag labels at the end of
the intensity bulletin, have been applied. For more details on these rules, see Sections 5E, 5F, and 5G.
Adjacent to the “CI#” value are the corresponding estimated mean sea level pressure (MSLP) and maximum wind (Vmax) values (see Sections 5I and 5O, depending upon method used). The MSLP value displayed for the derived CI# intensity estimate may have been modified by a latitude bias adjustment, which is a linear regression-based equation which adjusts the original CI# based upon the current storm latitude, or the Courtney/Knaff/Zehr (CKZ) adjustment (Section 5O).
If the Latitude Bias Adjustment methodology is used (not shown above), the amount of any adjustment will be listed below the CI#/Pressure/Vmax information next to the “Latitude Bias Adjustment to MSLP” label (see Section 5L). A positive/negative adjustment will increase/decrease the MSLP value obtained from the specific CI#/MSLP relationship for the scene being investigated. Please see Sections 5I and 5L for more information on this process.
If the CKZ MSLP determination method is used, a section at the bottom of the intensity bulletin will display the two input parameters used in the calculation (the Average 34 Knot Radii distance, in km, and the Environmental MSLP value, in mb). See Section 5O for more information.
Following the eye and cloud temperature information (Section 5C), the specific Scene Type and Positioning Method information is listed. The example above obtained a CLEAR EYE scene for a manually selected storm center location. The storm center selection method is provided in both the intensity bulletin and the preceding runtime messages section. A discussion of an automatically selected storm center location will be provided in Sections 4D4 and 5J. The scene type will be determined automatically using various image analysis methods (see Section 5B). Manual selection of the storm scene type can be performed using the OVER keyword described in Section 4A1.
If the scene type of the current analysis is an EYE, PINHOLE EYE, or a LARGE EYE, an estimate of the Radius of Maximum Wind (RMW) will be also be provided in the intensity bulletin. For information on the RMW value derivation see Section 5M.
The ocean basin in which the storm is located will be displayed next. This value will either be ATLANTIC, PACIFIC, or INDIAN. Following the ocean basin designation, the empirical T# to MSLP relationship method used to determine the MSLP value for the given T#/CI# is presented. This value will either be listed as ATLANTIC or PACIFIC, indicating the Atlantic or West Pacific empirical relationship conversion is used. The conversion will automatically be determined unless manually overridden using the DOMAIN keyword. See Section 5I for more information on the automatic ocean basin determination process and T# to MSLP conversion relationship.
The final three “Tno/CI Rules” entries inform the user whether the SDT “Rule 8” and/or “Rule 9” T#/CI# adjustments are being utilized. Constraint Limits will list which
