1. Christian Kummerow Colorado State University Chair, GEWEX Radiation Panel Fourth WCRP Observations and Assimilation Panel (WOAP) Meeting Date: 29-31 March 2009 University of Hamburg GEWEX Radiation Panel Report (Reprocessing)

2. 2 1979198519901995200020052010 Parameter Clouds Water Vapor TOA Radiation Precipitation SRF Radiation Atmospheric Circulation Evaporation TIME Pentad Daily 3 – 6 hrs 50 km 250 km 100 km 50 km 100 km Available Global Datasets

3. ISCCP Production Completed thru June 2008 CA=66.4% PC=573mb TAU=3.9 TC=261.6K

4. CALIBRATION EFFECTS TC TS TAU RS IRVIS

5. 5 ISCCP Reprocessing and Transition to Operations √ Code adapted to newer computers √ Code adapted to B1U Testing finer spatial test & sliding time window Testing new polar cloud detection IR retrieval code revised for better treatment of surface, will include aerosol VIS retrieval code revisions Tests of new products (scale dependence & sampling effects) Review & Revision of Calibration Re-run of QC statistics  Incorporate common ancillary information

6. 6 http://gewex-srb.larc.nasa.gov

7. Parameter Ohmura & Gilgen (1993) GEBA Surf. Obs. Trenberth et al. (2009) CERES and Models Zhang & Rossow (2004) 21-Year Mean (1984-2004) NASA/GEWEX SRB Release 3.0/2.5* (NASA LaRC) 24-Year Mean (July 1983 - June 2007) SW, LWSW, LW QC Flux% F 0 Flux% F 0 Flux% F 0 Flux% F 0 Flux% F 0 SW Down169.049.418453.9189.255.4188.755.2182.253.3 SW Net142.041.616147.2165.948.5166.648.7159.746.7 LW Down345100.933397.6343.8100.6343.2100.4347.5101.7 LW Net-40.0-11.7-63-18.5-49.6-14.5-52.8-15.4-51.2-15.0 Total Net102.029.89828.7116.334.0113.833.3108.531.7 SW CRF-- -53.0-15.5-58.8-17.2-60.9-17.8 LW CRF-- 4613.529.58.635.310.334.310.0 Total CRF-- -23.5-6.9-23.5-6.9-26.6-7.8 Global Multi-Year Averages S 0 = 1365 Wm -2 for Trenberth et al. and 1367 Wm -2 for all others *GEWEX LW values are Rel.-2.5 and 23-year averages (Jul1983-Jun2006) 7

8. 8 SRB Validation and Analysis Validation Analysis BSRN and other measurements Time series analysis (GEBA/BSRN data - Hinkelman et al, 2009) Clear/cloudy analysis with Long/Ackerman derived flux products Comparisons to other global flux: ISCCP FD, CERES data sets (Raschke et al., 2007, 2008; GEWEX-RFA) Analysis Contributions: Uncertainty & inputs assessment (Zhang et al 2006, 2007) Regional Radiation Budgets (Tibetan, Mediterranean) Cloud Forcing & Diurnal variability (Smith et al., 2008, 2009 conf) Global Energy Balance Assessment (Lin et al., 2008) Poleward Energy Transport (Zhang et al., 2008

9. 9 Validation Using BSRN Data (1992-2007) SW LW (1992 – 2005)

10. Global mean downwelling IR -- GCMs and BSRN estimate M. Wild 2001& 2005 Avg. (337) BSRN (344) Circa 2005 GCM models (global means) Over Last 6 Years, Climate Models Approach BSRN Downwelling IR Results BSRN (344 W m -2 ) Model Avg. (329) Circa 1999 GCM models (global means) E.G. Dutton 2009 GRP Meeting Rostock, Germany 13-16 Oct 2009 M. Wild JGR

11. 11 SRB Reprocessing Plans Evaluate and implement homogenization of SRB inputs/ancillary data sets. – Standardize surface topography => w/ISCCP – Surface and atmospheric temperature and water vapor profiles (alternative to GEOS-4, MERRA (GEOS-5)) => new HIRS, corrected TOVS, or reanalysis?? – Ozone and other trace gas concentrations => use ISCCP – Total solar irradiance and variability => new Kopp time series – Surface spectral emissivity annual variability => review w/ ISCCP – Surface spectral albedo treatments => update spectral models w/ U.Md; temporal change – Aerosol properties in climatological and historical sense => assess various data sets, i.e., GOCART, AEROCOM median, MATCH, etc. Implement/assess codes to process new ISCCP “NX” products for production of 1 o x1 o and/or 1/2 o x 1/2 o Assist in DCC technique for calibration New error handling

12. 12  Short term: Evaluate new HIRS product for use in combined data set  Longer term: Consider restarting a water vapor assessment. This should consider TPW, UTH and water vapor profiles separately over ocean and land.  GSICS is tackling the calibration and intercalibration of current satellite data streams  Data stewardship at NOAA has gained traction for calibration and intercalibration of historical data.  HIRS data is being reprocessed with uniform calibration  NVAP activity is again active under NASA MEASURES program.  Reanalyses getting better although artificial trends are problematic GRP Water Vapor Outlook (currently not a GEWEX product)

13. 13 Global Precipitation Climatology Project (GPCP) Adler, Huffman, Gu Year 2008 Added to GPCP Record—now 30 years

14. σ/mean 8 6 2 GPCP developing model for uncertainty 2.64 mm/day ± 9.5% 2.12 mm/day ± 7.5% 2.87 mm/day ± 10%

15. 15 GPCP Reprocessing Plan Tentative suite of Version 3 products (overlapping time resolutions) 3-hr [00Z, 03Z,….snapshot plus 3-hr total estimated for 00-03Z, 03-06Z, etc.] (0.25 °) 50N-50S (possibly 60° in some areas; incomplete grids); 1998- present (will test TMPA, CMORPH) Daily [00Z-00Z] (0.5°) global (1998-present; will use 3-hr product at low latitudes, current daily (1dd) product to complete globe; B1period [IR], (~1983-1997) PERSIANN for calibrated IR (50N-50S) Pentad (sum of daily), with current pentad technique to complete globe. Sub-monthly products forced to monthly--this is meant to constrain total of 3-hr or daily estimates which may vary during period Monthly (target: 0.5°) global; 1979-present (pre-1987 period will use B1 supplemented by OPI. (2 possible approaches for SSM/I period: 1 SSM/I and calibrated IR, or multiple SSM/I’s with correction for diurnal--remember 0.5° spatial resolution) Schedule Delivery of first month test inputs to merge center by Nov. 30, completion of suite of products for one year by end of April 2010; evaluation complete end of August; reprocessing to begin Oct. 2010 for completion in Fall 2011.

16. 197919821985198819911994199720002003200620092012 SeaWiFS MODIS/Terra MODIS/Aqua VIIRS NPP/NPOESS TOMS/Nimbus-7 TOMS/Earth Probe TOMS/Nimbus-7: 11/1/1978 - 5/6/1993, Earth Probe 7/96 – 5/01 AVHRR: NOAA-series August 1981 – present SeaWiFS: September 1997 – present MODIS Terra: February 2000 – present MODIS Aqua: July 2002 – present NPP VIIRS: 2010 – AVHRR/NOAA-series (7 and on) Courtesy, C. Hsu AURA/OMIPARASOL GEWEX Aerosol Climatology Project (GACP)

17. All intercomparisons have been completed Results are being shared with authors of other datasets Final draft with approval from other authors in December Aimed at BAMS/also in conjunction with JOFURO article SeaFlux Assessment

18. 1999 LH flux average

19. Latent Heat Flux Assessment

20. Trends in LH Flux (NN Winds)

22. 22 Example of monthly LE fluxes Monthly averaged latent fluxes (LE) August 1993 [W/m 2 ] 1.Introduction 2.Products 3.Examples 4.Annual means 5. Zonal means 6. Basins 7. Summary

23. 23 Reprocessing Plans for GPR products  Coordinated re-processing of all products using latest updates updates to code  Production of a merged data set for Water and Energy Variables. Uses common Ancillary Datasets (i.e. assumptions). All products going to 0.5° or 1°, 3-6 hr.

24. 24 COMMON DATASETS Topography and Land/Water Mask Ozone Snow/Ice Surface Albedo Surface Emissivity Atmospheric Temperature and Humidity T S & SST Aerosol Climatology or GACP

25. 25 SEA ICE Datasets Considered: NSIDC Bootstrap, GSFC Bootstrap, NASA Team Selected GSFC Bootstrap based on probability of existing in future

26. 3 ATMOSPHERIC TEMP. & HUMIDITY PROFILES Datasets Considered: TOVS operational (global 250-km since 1978), NRA1, ERA15, (NRA2, ERA40, ERA-Interim), MERRA, new-HIRS (preliminary) Issues: near-surface diurnal accuracy, length and homogeneity of record, continuation Sep01Oct01 TS – ME – TV2.63 (4.35)0.31 (6.29) K TS – ME – HIRS-2.53 (7.31)-5.22 (8.46) K TA – ME – TV-0.81 (4.65)-0.88 (4.44) K TA – ME – HIRS 5.06 (8.27) 5.25 (8.28) K PW – ME – TV0.14 (0.69)0.10 (0.73) cm PW – ME – HIRS-1.48 (1.18)-1.44 (1.18) cm

28. 28 Selection of Ancillary Datasets D-Topography – GTOPO30 plus AVHRR project mask D-Ozone – TOMS/OMI-based merger with polar TOVS (check earlier time period) D-Snow – NOAA product (check MODIS) D-Sea Ice – GSFC bootstrap with fill (check planned lifetime) I-Aerosols – GACP over oceans with median emissions model over land – matched at boundaries I-Atmospheric Temperature/Humidity – prefer new HIRS if current limitations can be resolved (surface topography, skin-air difference, recent calibration)

29. 29 RE-PROCESSING SCHEDULE Sequencing: Aerosol and Atmosphere  ISCCP  SRB  SeaFlux and LandFlux -- Atmosphere  GPCP Start in 2010 and Finish in 2011 Process in Reverse Chronological Order Beginning with 2009