1. 12/12/2009
Gauge + Satellite
Evaluation of precipitation from reanalyses and satellite products in Australia and East Asia
Gauge only
Jorge L. Peña Arancibia, Albert I.J.M. van Dijk, Luigi J. Renzullo and Tim Raupach, all at CSIRO
Mark Mulligan KCL
24 April 2012
CSIRO land and Water/water for a healthy country

2. Global satellite and reanalyses precipitation
Data and methods
NCEP-DOE, JRA-25, ERA-Interim,
TRMM 3B42 V6, CMORPH, PERSIANN
FD mapped ensemble precipitation
SILO (Jeffrey et al., 2001, ENVSOFT), APHRODITE SEA (Yatagai et al., 2009, SOLA)
Detection and agreement metrics for 2003– 2007 (rainfall >1mm d-1).
Six member statistics
EGU | Evaluation of reanalyses and satellite precipitation data

3. FD mapped ensemble
prob* is the probability of the value Pens on day i in the ensemble precipitation time series (Pens), Padj is the empirically adjusted precipitation time series, Pobs is the observed precipitation time series, Pens is the ensemble time series
EGU | Evaluation of reanalyses and satellite precipitation data

4. Detection: occurrence of precipitation
ETS
How well did the forecast "yes" events correspond to the observed "yes" events
(accounting for hits due to chance)?
EGU | Evaluation of reanalyses and satellite precipitation data

5. Detection: occurrence of precipitation
ETS
ETS
How well did the forecast "yes" events correspond to the observed "yes" events
(accounting for hits due to chance)?
Colour codes means best product: red for reanalysis and blue for satellite, ensemble black
EGU | Evaluation of reanalyses and satellite precipitation data

6. Detection: occurrence of precipitation
Range: -1/3 to 1, 0 indicates no skill.   Perfect score: 1.
ETS
EGU | Evaluation of reanalyses and satellite precipitation data

7. Agreement: quantity/timing of precipitation
Correlation
RMSD
Pmonth
Correlation
Pmonth: difference in the ratio of monthly precipitation amount to total days with precipitation
Pmonth
RMSD
EGU | Evaluation of reanalyses and satellite precipitation data

8. Agreement: quantity/timing of precipitation
Correlation
RMSD
Pmonth
Pmonth: difference in the ratio of monthly precipitation amount to total days with precipitation
EGU | Evaluation of reanalyses and satellite precipitation data

9. Agreement: quantity/timing of precipitation
Pmonth
RMSD
Correlation
Pmonth: difference in the ratio of monthly precipitation amount to total days with precipitation
EGU | Evaluation of reanalyses and satellite precipitation data

10. TS averaged over the entire domain
RMSD
ETS
Pmonth
Correlation
EGU | Evaluation of reanalyses and satellite precipitation data

11. Summary POD: probability of detection (0-1) perfect score 1
Diff
Rank
ETS
POD
FAR
BIAS
Correlation
RMSD
Pmonth (%) 1
0.27 (±0.05)
0.63 (±0.09)
0.43 (±0.07)
0.94 (±0.11)
0.42 (±0.09)
6.94 (±1.5)
1.83 (±11.8) 2
0.62 (±0.08)
0.46 (±0.06)
1.06 (±0.23)
0.40 (±0.08)
7.11 (±1.6)
-3.7 (±11.3) 3
0.26(±0.06)
0.55 (±0.07)
0.46 (±0.09)
0.93 (±0.21)
0.39 (±0.08)
7.16 (±1.6)
-10. (±11.3) 4
0.23 (±0.04)
0.57 (±0.09)
0.47 (±0.07)
1.13 (±0.14)
0.35 (±0.09)
7.72 (±1.7)
-11. (±7.21) 5
0.20 (±0.05)
0.44 (±0.07)
0.48 (±0.07)
0.82 (±0.11)
0.31 (±0.05)
8.10 (±1.6)
-11. (±9.71) 6
0.20 (±0.06)
0.42 (±0.07)
0.48 (±0.10)
1.21 (±0.25)
0.31 (±0.09)
8.18 (±1.8)
28.0 (±7.99) 7
0.11 (±0.04)
0.34 (±0.07)
0.59 (±0.09)
1.29 (±0.14)
0.15 (±0.05)
10.9 (±2.5)
33.2 (±12.2)
NCEP-DOE
JRA-25
ERA-Interim
TRMM 3B42 V6
CMORPH
PERSIANN
Ensemble
POD: probability of detection (0-1) perfect score 1
FAR: false alarm ratio (0-1) perfect score 0
BIAS: bias in over (>1) or underdetecting (<1) perfect score 1
EGU | Evaluation of reanalyses and satellite precipitation data

12. and the winner is…ensemble!!!
Summary
Diff
Rank
ETS
POD
FAR
BIAS
Correlation
RMSD
Pmonth (%) 1
0.27 (±0.05)
0.63 (±0.09)
0.43 (±0.07)
0.94 (±0.11)
0.42 (±0.09)
6.94 (±1.5)
1.83 (±11.8) 2
0.62 (±0.08)
0.46 (±0.06)
1.06 (±0.23)
0.40 (±0.08)
7.11 (±1.6)
-3.7 (±11.3) 3
0.26(±0.06)
0.55 (±0.07)
0.46 (±0.09)
0.93 (±0.21)
0.39 (±0.08)
7.16 (±1.6)
-10. (±11.3) 4
0.23 (±0.04)
0.57 (±0.09)
0.47 (±0.07)
1.13 (±0.14)
0.35 (±0.09)
7.72 (±1.7)
-11. (±7.21) 5
0.20 (±0.05)
0.44 (±0.07)
0.48 (±0.07)
0.82 (±0.11)
0.31 (±0.05)
8.10 (±1.6)
-11. (±9.71) 6
0.20 (±0.06)
0.42 (±0.07)
0.48 (±0.10)
1.21 (±0.25)
0.31 (±0.09)
8.18 (±1.8)
28.0 (±7.99) 7
0.11 (±0.04)
0.34 (±0.07)
0.59 (±0.09)
1.29 (±0.14)
0.15 (±0.05)
10.9 (±2.5)
33.2 (±12.2)
NCEP-DOE
JRA-25
ERA-Interim
TRMM 3B42 V6
CMORPH
PERSIANN
Ensemble
and the winner is…ensemble!!!
EGU | Evaluation of reanalyses and satellite precipitation data

13. and the winner is…ensemble!!! But not a fair comparison!!!
Summary
Diff
Rank
ETS
POD
FAR
BIAS
Correlation
RMSD
Pmonth (%) 1
0.27 (±0.05)
0.63 (±0.09)
0.43 (±0.07)
0.94 (±0.11)
0.42 (±0.09)
6.94 (±1.5)
1.83 (±11.8) 2
0.62 (±0.08)
0.46 (±0.06)
1.06 (±0.23)
0.40 (±0.08)
7.11 (±1.6)
-3.7 (±11.3) 3
0.26(±0.06)
0.55 (±0.07)
0.46 (±0.09)
0.93 (±0.21)
0.39 (±0.08)
7.16 (±1.6)
-10. (±11.3) 4
0.23 (±0.04)
0.57 (±0.09)
0.47 (±0.07)
1.13 (±0.14)
0.35 (±0.09)
7.72 (±1.7)
-11. (±7.21) 5
0.20 (±0.05)
0.44 (±0.07)
0.48 (±0.07)
0.82 (±0.11)
0.31 (±0.05)
8.10 (±1.6)
-11. (±9.71) 6
0.20 (±0.06)
0.42 (±0.07)
0.48 (±0.10)
1.21 (±0.25)
0.31 (±0.09)
8.18 (±1.8)
28.0 (±7.99) 7
0.11 (±0.04)
0.34 (±0.07)
0.59 (±0.09)
1.29 (±0.14)
0.15 (±0.05)
10.9 (±2.5)
33.2 (±12.2)
NCEP-DOE
JRA-25
ERA-Interim
TRMM 3B42 V6
CMORPH
PERSIANN
Ensemble
and the winner is…ensemble!!! But not a fair comparison!!!
EGU | Evaluation of reanalyses and satellite precipitation data

14. Conclusion
Similar findings to other studies in different geographical domains (e.g. Ebert et al., BAMS)
Other sources of error
Enhancement of metrics when producing ensembles
Importance of ground monitoring networks, particularly were satellite/reanalysis algorithms need refinement and evaluation
More confidence in areas were ground monitoring is scarce
HS1 A276 poster Tuesday 24
EGU | Evaluation of reanalyses and satellite precipitation data

15. HS1 A276 poster http://eos.csiro.au/
EGU | Evaluation of reanalyses and satellite precipitation data

16. Thank you CSIRO Land and Water Jorge Luis Peña Arancibiae w
CSIRO Land and water