1. BLUElink> Regional High-Resolution SST Analysis System – Verification and Inter-Comparison Helen Beggs Ocean & Marine Forecasting Group, BMRC, Bureau of Meteorology Presented at 8 th GHRSST-PP Science Team Meeting, Melbourne, 14-18 May 2007

2. BLUElink> Regional High-Resolution SST Analysis System Based on BoM operational, optimal interpolation SST analysis system Resolution: Daily, 1/12° Region: 60°E - 170°W, 20°N - 70°S Data sources: AVHRR SST1m (Local 1km, Global 9km x 4 km) AATSR Meteo SSTskin (17km) AMSR-E SSTsubskin L2P (25 km) In situ bulk SST from GTS NCEP ice edge data Test daily foundation SST analyses available by ~0230 UT (fv01) and ~2030 UT (fv02) as GHRSST-PP GDS v1.7 netCDF L4 files from OPeNDAP server accessible via: http://godae.bom.gov.auhttp://godae.bom.gov.au More information on the analysis system: http://www.bom.gov.au/bmrc/ocean/BLUElink/SST/Bureau_HR_Regional_S ST_Analysis_vg1.0.pdf

3. How does BLUElink> test 1/12° regional SSTfnd analysis compare with other SST analyses/composite products over the same region (20°N to 70°S, 60°E to 170°W)?

4. Data Inputs to L4/L3 SST products over Australian region L4/L3 ProductGAC AVHRR (~1m) HRPT AVHRR (~1m) AMSR-E (subskin) AATSR (skin) TMI (subskin) In Situ (bulk) BoM 1/12° regional SSTfnd XXXXX BoM 1/4° regional SST1m XXX OSTIA 1/20° global SSTfnd XXXXX Reynolds 1/4° AMSR+AVHRR SSTblend XXX CSIRO 1/25° 3 Day AVHRR Composite SST1m X

5. BoM Operational Regional SST1mReynolds AMSR-E+AVHRR SSTblend CSIRO 3 Day AVHRR SST1mMet Office Global OSTIA SSTfnd

6. Reynolds AMSR-E+AVHRR SSTblend minus OSTIA SSTfnd

7. BoM Gamma Test SSTfnd Analysis minus Other SST Analyses/Composites Over region: 60°E - 180°E, 20°N - 70°S Period: 1 Oct – 30 Nov 2006 Test – BoM Operational Regional SST1m: 0.07 ± 0.41°C Test – CMAR Composite AVHRR SST1m: -0.15 ± 0.73°C Test – OSTIA SSTfnd: 0.09 ± 0.45°C Test – Reynolds SSTblend:-0.02 ± 0.61°C

8. How do we assess how “good” analyses are?

9. GODAE Level 4 Analysis Metrics Performance Analysis – Diagnostics based on statistical measures Innovation Vector (Obs - BGF and rms(Obs – BGF)) Withheld Observations (Analysis (no buoy data) – Buoy SST) Quality Analysis – Based on direct comparisons with observations Consistency Analysis – Based on understanding of ocean Can use animations

10. Performance Analysis … BoM Analysis Statistics: 1 Oct – 30 Nov 2006 Operational SST1m Beta Test SSTfnd Gamma Test SSTfnd

11. Quality Analysis … Analysis/Composite SST minus Buoy SSTfnd Over region: 60°E - 180°E, 20°N - 70°S Period: 1 Oct – 30 Nov 2006 BoM Operational Regional SST1m:-0.08 ± 0.44°C BoM Beta Test Regional SSTfnd:-0.08 ± 0.42°C BoM Gamma Test Regional SSTfnd:-0.01 ± 0.29°C (0.03 ± 0.49°C) CMAR Composite AVHRR SST1m: -0.01 ± 0.62°C OSTIA SSTfnd: -0.07 ± 0.24°C Reynolds AMSR-E+AVHRR SSTblend:-0.04 ± 0.52°C No Buoy Data

12. Consistency analysis…

13. NOAA Daily Reynolds SSTblendBoM Daily Gamma Test Regional SSTfnd CSIRO 3 Day Daily AVHRR SST1mMet Office Daily Global OSTIA SSTfnd

14. NOAA Daily Reynolds SSTblendBoM Daily Gamma Test Regional SSTfnd BoM Operational Regional SST1mMet Office Daily Global OSTIA SSTfnd

15. NOAA Daily Reynolds SSTblendBoM Daily Gamma Test Regional SSTfnd CSIRO 3 Day Daily AVHRR SST1mMet Office Daily Global OSTIA SSTfnd

16. Conclusions Over the study period (1 Oct – 30 Nov 2006) BoM Gamma Test SSTfnd Analyses – Have less bias and RMS error than BoM Operational or Beta Test Regional SST analyses (based on Obs – Analysis, Obs – BGF and Analysis – Buoy Obs) – Agree more closely with OSTIA SSTfnd analyses than Reynolds AMSR-E+AVHRR SSTblend or CSIRO’s 3 Day AVHRR SST1m Composite – More closely resolve meso-scale ocean features than 1/20° resolution OSTIA SSTfnd analyses – Exhibit better temporal consistency between daily analyses but less spatial homogeneity than OSTIA Parallel tests with LAPS0.125 and LAPS0.05 (Sydney) ingesting Gamma SSTfnd and BoM operational regional SST1m currently underway to determine impact on skill.

18. NOAA Daily Reynolds SSTblendGamma Test SSTfnd (BGFCLS = 50 km) CSIRO 3 Day Daily AVHRR SST1mMet Office Daily Global OSTIA SSTfnd

19. NOAA Daily Reynolds SSTblendBoM Daily Gamma Test Regional SSTfnd CSIRO 3 Day Daily AVHRR SST1mMet Office Daily Global OSTIA SSTfnd

20. Drifting + Moored Buoys

21. Local 1 km AVHRRGlobal 9 km x 4 km AVHRR Global 17 km AATSRGlobal 25 km AMSR-E

22. 1/12° SSTfnd Analysis

23. BLUElink SSTfnd Analysis Blending Method AATSR skin SST converted to foundation using empirical Donlon et al (2002) cool skin parameterisation. Remove daytime data with LAPS winds < 6 m/s, night-time data with LAPS winds < 2 m/s.

24. Filtering for Diurnal Warming Events (1 – 30 Nov 2006: 60°E - 190°E, 20°N - 70°S)