Analysis of Doppler Radar Datasets

L. Jay Miller (September 2009)

Gridding and Wind Synthesis

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EOL/RSF Project

• “Unfreeze” legacy software• REORDER – NCAR/ATD/FOF (Dick Oye)

• SPRINT – NCAR/MMM (Carl Mohr and L. Jay Miller)

• CEDRIC – NCAR/MMM (Carl Mohr and L. Jay Miller)

• PPI_MMM – NCAR/MMM (Carl Mohr and L. Jay Miller)

• Other contributors: Michele Case (ATD/FOF)Bill Anderson (MMM)Sherrie Fredrick (MMM)

• History of software• SPRINT – Late 1970s (NHRE)

• REORDER – Mid 1980s (ELDORA)

• CEDRIC – Late 1970s – Early 1980s (NHRE and CCOPE)

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EOL/RSF Project cont’d

• Evaluate gridding software

• Recommendations for future

• Establish single repository

• Include legacy software

• Document efforts with Wiki website

• Knowledge transfer and document usage

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Comparison of Reorder and Sprint

REORDER SPRINT

SCHEME:DISTANCE-WEIGHTING BI-LINEAR INTERPOLATIONCLOSEST POINT CLOSEST POINT

REGION OF INFLUENCE:USER-SPECIFIED RADII LOCALLY ADAPTIVEXYZ ORIENTED RAE ORIENTED

CONSEQUENCES:CONSTANT LINEAR SCALE UNEQUAL LINEAR SCALEUNEQUAL ERROR CONSTANT ERROR

GROUND-BASED (AIRBORNE) OUTPUT GRID ORIENTATION:

USER SPECIFIES + X AZIMUTH USER SPECIFIES + X AZIMUTH(USER-SPECIFIES + X AZIMUTH) (+ X – OUT RIGHT SIDE)

(+ Y – FLIGHT DIRECTION)(ROTATE TO SPECIFIED + X AZIMUTH)

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Common Characteristics

• Read DORADE and Universal formats• DB Fields Linear Interpolate DB Scale• Radial velocity interpolation includes

local unfolding • Output CEDRIC pure binary files

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Sprint-Reorder Interpolation Regions

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Airborne Grid Orientations

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Analysis Flow Chart for COPS

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reorder_dows

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Parts of run_cedsyn

• Part 1 (BEGIN): Basic framework for processing single radar dataset

• Part 2 (FIL_GRAF): Define block used reading/massaging/graphing single radar

• Part 3 (SYNUVW): Define block used for synthesis, creating additional fields, graphing, and writing these final results

• Part 4 (PATCHER): Commands for additional filling of fields

• Part 5 (FILTER): Commands for filtering and creating new fields

• Part 6 (COMPARE): Commands for comparing input and output fields

• Part 7 (FINISH): Commands for finishing and writing synthesis output

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Part 1: run_cedsyn (BEGIN)

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Part 2: run_cedsyn (FIL_GRAF)

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Part 3: run_cedsyn (SYNUVW)

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Part 4: run_cedsyn (PATCHER)

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Part 5: run_cedsyn (FILTER)

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Part 6: run_cedsyn (COMPARE)

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Part 7: run_cedsyn (FINISH)

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Some Relevant Websites

• EOL/RSF PROJECT WIKI: https://wiki.ucar.edu/display/raygridding/Home

• CEDRIC DOCUMENTATION: http://www.mmm.ucar.edu/pdas/Documentation

• PURE BINARY FILE DESCRIPTION: http://www.mmm.ucar.edu/pdas/Documentation/appendix-D.ps

• WIND SYNTHESIS MATH: http://www.mmm.ucar.edu/pdas/Documentation/appendix-F.ps

• AIRBORNE DOPPLER RADAR DATA ANALYSIS WORKSHOP (2000)http://www.mmm.ucar.edu/pdas/ATD-workshop/atd-lecture.html