1. 1 CF Unleashed: Introduction to Cf/Radial Joe VanAndel National Center for Atmospheric Research vanandel@ucar.edu 2013/1/8 The National Center for Atmospheric Research is sponsored by the National Science Foundation

2. 2 CF -What is it? Climate and Forecast Metadata Convention Locate data in space–time and as a function of other independent variables, to facilitate processing and graphics for –model-generated data –observational datasets originally no support for radial data 2

3. 3 Motivation Support radar/lidar community Provide better interoperability for data providers and tool creators provide libraries and tools to –read/write datasets –convert from legacy formats –display radial data

4. 4 What is Cf/Radial? CF extensions for radial radar/lidar data CF compliant netCDF –netCDF is familiar to many scientists –CF allows assimilating data into forecast models Details: http://www.ral.ucar.edu/projects/titan/docs/ radial_formats http://www.ral.ucar.edu/projects/titan/docs/ radial_formats 4

5. 5 What Kind of Instruments? Scanning Staring Vertically Pointing Mobile or Fixed 5

6. 6 Stationary Scanning 6

7. 7 Mobile/Scanning 7

8. 8 Airborne Scanning Radar 8

9. 9 Airborne Vertically Pointing 9

10. 10 Fixed, Staring Profilers 10

11. 11 Advantages Readable on Linux, OS X, Windows Supported by multiple languages: –C/C++ –Fortran –Python –IDL –Matlab 11

12. 12 Advantages (2) Byte order independent Efficient storage: –supports variable gates/beam –native compression 12

13. 13 Staggered 2-D Storage 13

14. 14 Transparent Compression NetCDF4 uses HDF5 as storage layer NetCDF4/HDF5 supports transparent compression compressed files can be as small as 20% of the original size (data dependent) 14

15. 15 Sample Surveillance Data 15

16. 16 Range Height Radar Data 16

17. 17 Lidar Data 17

18. 18 Data Content Overview data fields (moments) each moment is a collection of “Rays” each ray has range gates 18

19. 19 Metadata each ray has metadata: –range –elevation –latitude –longitude –altitude –time 19

20. 20 Metadata(2) Moving platforms: –heading –roll –pitch –rotation –tilt 20

21. 21 Coordinate Conventions Fixed location Mobile ground-based (truck mounted radars) Airborne radars/lidars 21

22. 22 Current tools Radx C++ library Conversions: Read/Write CfRadial DORADE (legacy binary radar format) Universal Format (UF) - very old binary format NEXRAD level 2 archive Foray1 (EOL netCDF) SIGMET (writing is not supported) 22

23. Future work (1) Incorporating metadata from NODC netCDF templates Incorporating metadata from NetCdf Attribute Convention for Data Discovery 23

24. 24 Future work (2) convert SOLO (display/editing tool) to read/write CfRadial Python libraries and tools Matlab libraries IDL libraries Community archive of user contributed libraries and tools. 24

25. 25 Who is using CfRadial? NCAR UNIDATA DOE/ARM NOAA/NSSL EEC (commercial radar vendor) Pro Sensing (commercial radar vendor) Various university users 25

26. 26 Conclusion Want to encourage more users to adopt CfRadial We welcome your ideas on how to publicize this format NCAR is supported by the National Science Foundation.

27. 27 Acknowledgements 27 Co-Authors: Mike Dixon Wen-Chau Lee Bob Rilling Chris Burghart

28. 28 Questions? 28 ? ? ?