1. Qc2 Development

2. Recap from last meeting 20081119:
Linear Interpolation with Triangulated Neighbours
Test Results of RARR_24
Inverse Distance Squared Interpolation
Above cross-validation analysis courtesy of Matthias Mohr
The standard deviations of the error in precipitation amount are not very different (3.5 mm for triangulation and 3.7 for inverse distance squared)

3. Developments/Ongoing
Recap from last meeting :
Developments/Ongoing
Test Tools: unit tests, automatic result plotting from algorithms and netCDF files,
Interpolation options: inverse-N distance weighting, triangulation, height normalisation,
General tidying and improved encapsulation, including flags,
Wet/Dry discrimination,
Interface to preferred neighbours station list, e.g. for triangulation,
Interface to PROJ Cartographic Projections Library including geographic to UTM for linear interpolation,
Expand the configuration file options,
Time interpolation strategies.

4. Developments
Test Tools: unit tests, automatic result plotting from algorithms and netCDF files,
Interpolation options: inverse-N distance weighting, triangulation, height normalisation,
General tidying and improved encapsulation, including flags,
Wet/Dry discrimination,
Interface to preferred neighbours station list, e.g. for triangulation,
Interface to PROJ Cartographic Projections Library including geographic to UTM for linear interpolation,
Expand the configuration file options,
Time interpolation strategies.
Test environment with Terje
Need for filter of duplicate data arising from multiple typeids. Identification of the ”official value”.
New …

5. Time series interpolation

6. Example 1: [multiple strategies]

7. Comparison with nearest neighbour

8. *NB Ole-Einer og Matthias have better methods
Height correction [0.006*dHt]*
*NB Ole-Einer og Matthias have better methods

9. Spline interpolation :: Akima
Note agreement/disagreement of spatial and temporal methods
Full variational analysis: combine both?

10. Example 2: [single points]

11. | 0.2|211|311|0|0|0.2| |-32767|211|311|0|0|0.7| | 1.1|211|311|0|0|1.1|
76330| :00:00 | 0.2|211|311|0|0|0.2| | |
76330| :00:00 |-32767|211|311|0|0|0.7| | C1|QC :1,hqc,hqc
76330| :00:00 | 1.1|211|311|0|0|1.1| | |
| 0.2|211|311|0|0|0.2|
|-32767|211|311|0|0|0.7|
| 1.1|211|311|0|0|1.1|

12. 76330| :00:00 | 0.2|211|311|0|0|0.2| | |
76330| :00:00 |-32767|211|311|0|0|0.7| | C1|QC :1,hqc,hqc
76330| :00:00 | 1.1|211|311|0|0|1.1| | |

13. Height corrected nearest neighbour
76330| :00:00 | 0.2|211|311|0|0|0.2| | |
76330| :00:00 |-32767|211|311|0|0|0.7| | C1|QC :1,hqc,hqc
76330| :00:00 | 1.1|211|311|0|0|1.1| | |
Height corrected nearest neighbour x

14. Thanks to Zbigniew for identifying the application of TAN & TAX
76330| :00:00 | 1.2 | 215 | 311 | 0 |0 | 1.2 | | |
76330| :00:00 | 0.9 | 213 | 311 | 0 |0 | 0.9 | | |
Best estimate for single missing temperature = 0.5*(TAN + TAX) ?
Thanks to Zbigniew for identifying the application of TAN & TAX

15. Next steps
Large-scale statistical analysis of results to converge on best strategies,
Identification and porting (if required) of most effective spline-fitting, Akima, etc. algorithms / library,
Input on algorithms welcome,
Kriging!

16. Test environment

17. https://dokit.met.no/sysdok/kvalobs/driftsdokumentasjon
Special thanks to quality assurance work from Terje, Bjørn, …

18. Test environment Operations QC2 QC1 db
Achieved in vm and in earlier work.
Test environment
QC2 db
QC1
Static test
population
Operations

19. Test environment ? ? ? Operations vm objectives QC2 QC1 db db QC0
HQC
Simulator ? db
QC1
Validate Output
QC0 ? ? db
Operations

20. Duplicate data filter …

21. Duplicate Data Filter Why How
need to identify official value for each time where duplicates exist
use one value for time and space interpolations
all algorithms complicated by duplicates
avoid more lengthy bug searches
How
specification of rules to identify official value
specification of required configuration information
define a universal flag to identify the official value in all circumstances
Need for input to define these requirements

22. Tusen takk!