1. Surface Skin/Air Temperature and LW Flux Calculation Y-C. Zhang and W.B. Rossow LandFlux Conference CNES/CESBIO, Toulouse, France May 28 – 31, 2007

2. 2 OUTLINE I. Datasets Used II. SRF Skin Temperature (Ts) Comparison: FD vs ERA15, GEOS-1, NCEP and 3I III. SRF Air Temperature (Ta) Comparison: FD vs ERA15, GEOS-1, NCEP and 3I, and SOBS IV. (Ts –Ta) Comparison: FD vs ERA15,GEOS-1, NCEP and 3I V. SRF LW Comparison: FD vs CERES VI. SRF LW and Ta Comparison: FD vs SOB VII. SRF LW Comparison: FD vs SRB VIII. Uncertainties of Ts, Ta and Others and their Caused Global, Daily-Mean LW Uncertainties

3. 3 I. Datasets Used 1. FDTV (TV) = ISCCP D1 W/ TOVS and FD Flux Product ► Original Temperature and Humidity Profile From TOVS Ts = Skin Temperature is retrieved from ISCCP production Ta = SRF air temperature is interpolated from TOVS profile Both land Ta and Ts are diurnal-adjusted using SOBS/NCEP Climatology ► Features: Spatial Resolution: Horizontal: 280 km equal area Vertical: up to 9 layers from SRF  10 hPa Temporal resolution: 3-hourly and its monthly hourly/monthly mean Spatial coverage: global Temporal Coverage: 1983 – 2004 (  2006 SOON) ► ISCCP-FD is a self-consistent and physically-integrated, SRF-to-TOA profile flux product, including all up & down, SW (diffuse/direct and VIS/NIR) and LW for full, clear and overcast sky, calculated using the NASA GISS radiative model with input datasets mainly from ISCCP-D1

4. 4... I. Datasets Used 2. ER = ERA-15 Reanalysis Product from ECMWF ► Temperature and Humidity Profile and Ts/Ta Used Ta is interpolated from profile ► Features: Spatial resolution: Horizontal: 2.5 ° X 2.5° (Averaged to 280 km equal area) Vertical: 17 Levels from 1000  10 hPa Temporal resolution: 6-hour monthly hourly, daily & monthly mean Spatial coverage: global Temporal Coverage: 1979 – 1993

5. 5... I. Datasets Used 3. GE = GEOS-1 Reanalysis Product from NASA ► Temperature and Humidity Profile and Ts Used Ta is interpolated from profile ► Features: Spatial Resolution: Horizontal: 2.5 ° X 2.0° (Averaged to 280 km equal area) Vertical: 18 levels from 1000  20 hPa Temporal resolution: 6-hour monthly hourly, daily & monthly mean Spatial coverage: global Temporal Coverage: 1980 – 1995

6. 6... I. Datasets Used 4. NC = NCEP Reanalysis Product (version 1) ► Temperature and Humidity Profile and Ts/Ta Used Ta is interpolated from profile ► Features: Spatial resolution: Horizontal: 2.5 ° X 2.0° (Averaged to 280 km equal area) Vertical: 8 levels from 925  100 hPa Temporal resolution: daily & monthly mean Spatial coverage: global Temporal Coverage: 1948 – 1998

7. 7... I. Datasets Used 5. 3I = Product based on Improved Initialization Inversion from LMD ► Temperature and Humidity Profile and Ts Ta is interpolated from profile ► Features: Spatial resolution: Horizontal: 1 ° X 1° (Averaged to 280 km equal area) Vertical: 9 layers from SRF  15 hPa Temporal resolution: Am & PM daily, 5-day & monthly mean Spatial coverage: global Temporal Coverage: 1988 – 1997

8. 8... I. Datasets Used 6. SOBS = Extended Editorial Synoptic Cloud Reports Archive ► Station-based Surface Air Temperature and Humidity, and clouds, etc. ► Features: Temporal resolution: 3-hourly & monthly mean Spatial coverage: about 6400 stations over globe Temporal Coverage: 1971 – 1996 for Land

9. 9... I. Datasets Used 7. CERES Flux Product ► Version: SRBAVG Ed. 2 Rv. 1 from GEWEX-RFA website ► Satellite: TERRA FM1 or FM2, XTRK and GEO-interpolated ► SRF (and TOA) up & down, SW and LW for all and clear sky Spatial resolution: horizontal: 2.5° X 2.5° Temporal resolution: monthly mean (based on original 3-hourly CERES) Spatial coverage: global Temporal coverage: March 2000 → ► Radiative Model for SRF fluxes: Model B: LPSA/LPLA (Langley Parameterized SW/LW Algorithm) based on the relationships with TOA fluxes and atmospheric data

10. 10... I. Datasets Used 8. GEWEX-SRB Flux Product ► Version: SW Rel 2.5 and LW Rel 2.6 (from Paul Stackhouse) ► SRF (and TOA) up & down, SW and LW for all- and clear sky Spatial resolution: 1° X 1° (Averaged to 280 km equal area) Temporal resolution: 3-houly (UTC = 0, 3, … 21) Spatial coverage: global Temporal coverage: July 1983 → Dec. 2004 ► Radiative Model: SW (0.2 – 4.0 μm) from Pinker/Laszlo (quality check by Staylor Model) LW (4.5 – ∞ μm) from Fu/Liou, (quality check by Gupta Model)

11. 11... I. Datasets Used 9. SOB = Surface Station Observed Flux Product containing some meteorological parameters ► Based on 15 selected stations of BSRN, ARM and SURFRAD networks obtained from GEWEX-RFA (Processed by Chuck Long) ► Ta is supplied (but not Ts) ► SRF down and up, SW (diffuse and direct) and LW and their inferred clear- sky fluxes, etc. Temporal resolution: 15-minute (averaged from original 1-3 min) (Averaged to 8 Local Solar time or daily/monthly mean) Temporal coverage: 2004 for 15-min daily 1992-2004 for monthly-mean 15-min ► Processing method: “Next Generation Flux Analysis” (NGFA) method

12. 12 II. SRF Ts Comparison: FD vs ER, GE, NC and 3I Global mean difference (STDV); ABS Mean is from column modulus mean

13. 13 …II. SRF Ts Comparison: FD vs ER, GE, NC and 3I Zonal-mean difference of monthly means with TV for Land and July

14. 14 …II. SRF Ts Comparison: FD vs ER, GE, NC and 3I Zonal-mean difference of monthly means with TV for Land and January

15. 15 …II. SRF Ts Comparison: FD vs ER, GE, NC and 3I Seasonal Cycle of monthly means: N. Hemispheric Land

16. 16 …II. SRF Ts Comparison: FD vs ER, GE, NC and 3I Seasonal Cycle of monthly means: S. Hemispheric Land

17. 17 …II. SRF Ts Comparison: FD, ER and GE Diurnal Cycle of monthly-hourly means: N. Hemisphere for Land and July

18. 18 …II. SRF Ts Comparison: FD, ER and GE Diurnal Cycle of monthly-hourly means: N. Hemisphere for Land and January

19. 19 …II. SRF Ts Comparison: FD, ER and GE Diurnal Cycle of monthly-hourly means: 25° N – 65° N mean for Land and July

20. 20 …II. SRF Ts Comparison: FD, ER and GE Diurnal Cycle of monthly-hourly means: 25° N – 65° N mean for Land/January

21. 21 III. SRF Ta Comparison: FD vs ER, GE, NC and 3I Global mean difference and its STDV; ABS Mean is from column modulus mean

22. 22 …III. SRF Ta Comparison: FD vs ER, GE, NC and 3I Zonal-mean difference of monthly means with TV for Land and July

23. 23 …III. SRF Ta Comparison: FD vs ER, GE, NC and 3I Zonal-mean difference of monthly means with TV for Land and January

24. 24 …III. SRF Ta Comparison: FD vs ER, GE, NC and 3I Seasonal Cycle of monthly means: N. Hemispheric Land

25. 25 …III. SRF Ta Comparison: FD vs ER, GE, NC and 3I Seasonal Cycle of monthly means: S. Hemispheric Land

26. 26 …III. SRF Ta Comparison: FD, ER and GE Diurnal Cycle of monthly-hourly means: N. Hemisphere for Land and July

27. 27 …III. SRF Ta Comparison: FD, ER and GE Diurnal Cycle of monthly-hourly means: N. Hemisphere for Land and January

28. 28 …III. SRF Ta Comparison: FD, ER and GE Diurnal Cycle of monthly-hourly means: 25° N – 65° mean for Land and July

29. 29 …III. SRF Ta Comparison: FD, ER and GE Diurnal Cycle of monthly-hourly means: 25° N – 65° mean for Land/January

30. 30 …III. SRF Ta Comparison: FD vs SOBS Diurnal Cycle of monthly-hourly means: 25 N – 65 N mean for Land and January 88º – 54º S FDTV underestimate inversion strength in Winter

31. 31 …III. SRF Ta Comparison: FD vs SOBS Central USA Diurnal Cycle for July 1992

32. 32 …III. SRF Ta Comparison: FD vs SOBS Central Asia Diurnal Cycle for July 1992

33. 33 …III. SRF Ta Comparison: FD vs SOBS Brazil Diurnal Cycle for July 1992

34. 34 IV. SRF (Ts – Ta) Comparison: FD vs ER, GE, NC and 3I Zonal-mean difference of monthly means with TV for Land and July

35. 35 …IV. SRF (Ts – Ta) Comparison: FD vs ER, GE, NC and 3I Zonal-mean difference of monthly means with TV for Land and January

36. 36 …IV. SRF (Ts – Ta) Comparison: FD vs ER, GE Diurnal Cycle for Global Land for July 1992

37. 37 …IV. SRF (Ts – Ta) Comparison: FD vs ER, GE Diurnal Cycle for 25º N – 65º N Land for July 1992

38. 38 V. SRF LW Comparison: FD vs. CERES Averaged from 36-month (0003 to 0302) Global, monthly-mean statistics; LW in W/m 2 ; Cor… are without unit

39. 39 … V. SRF LW Comparison: FD vs. CERES Averaged from 36-month (0003 to 0302) Land, monthly-mean statistics; LW in W/m 2 ; Cor… are without unit

40. 40 Annual-mean Difference between FD and CERES Clear-sky SRF LW-dw (W/m 2 ) for Land

41. 41 Annual-mean Difference between FD and CERES Clear-sky SRF LW-up (W/m 2 ) for Land

42. 42 Annual-mean Difference between FD and CERES Clear-sky SRF LW-Net (W/m 2 ) for Land

43. 43 Annual-mean Difference between FD and CERES Full-sky SRF LW-dw (W/m 2 ) for Land

44. 44 Annual-mean Difference between FD and CERES Full-sky SRF LW-up (W/m 2 ) for Land

45. 45 Annual-mean Difference between FD and CERES Full-sky SRF LW-Net (W/m 2 ) for Land

46. 46 Annual-mean Difference between FD and CERES Cloud Effects of SRF LW (net) (W/m 2 ) for Land

47. 47 VI. SRF LW and Ta Comparison: FD vs SOB 15 BEST Stations Selected from BSRN, ARM and SURFRAD networks

48. 48 …VI. SRF LW and Ta Comparison: FD vs SOB Statistics for all 2004 Local solar Noon of 3-hr mean from 15 Best Stations Flux in W/m 2 and Temperature in K Note: For all the available monthly means from all the stations, FD and BSRN have about 2 w/m 2 bias (high) with STDV < 20 w/m 2.

49. 49 Clear-sky SRF LW-dw (W/m 2 ) Comparison: FD vs. SOB for all 2004 Local solar Noon of 3-hr mean from 15 Best Stations

50. 50 Clear-sky SRF LW-up (W/m 2 ) Comparison: FD vs. SOB for all 2004 Local solar Noon of 3-hr mean from 15 Best Stations

51. 51 Clear-sky SRF LW-NET-LOSS (W/m 2 ) Comparison: FD vs. SOB for all 2004 Local solar Noon of 3-hr mean from 15 Best Stations

52. 52 Full-sky SRF LW-dw (W/m 2 ) Comparison: FD vs. SOB for all 2004 Local solar Noon of 3-hr mean from 15 Best Stations

53. 53 Full-sky SRF LW-up (W/m 2 ) Comparison: FD vs. SOB for all 2004 Local solar Noon of 3-hr mean from 15 Best Stations

54. 54 Full-sky SRF LW-NET-LOSS (W/m 2 ) Comparison: FD vs. SOB for all 2004 Local solar Noon of 3-hr mean from 15 Best Stations

55. 55 SRF Air Temperature (K) Comparison: FD vs. SOB for all 2004 Local solar Noon of 3-hr mean from 15 Best Stations

56. 56 Clear-sky LW-dw (W/m2) Diurnal Cycle Comparison: FD vs. SOB 3-hr mean averaged from all 15 Best Stations

57. 57 Clear-sky LW-up (W/m2) Diurnal Cycle Comparison: FD vs. SOB 3-hr mean averaged from all 15 Best Stations

58. 58 Clear-sky LW-NET-LOSS (W/m2) Diurnal Cycle Comparison: FD vs. SOB 3-hr mean averaged from all 15 Best Stations

59. 59 Full-sky LW-dw (W/m2) Diurnal Cycle Comparison: FD vs. SOB 3-hr mean averaged from all 15 Best Stations

60. 60 Full-sky LW-up (W/m2) Diurnal Cycle Comparison: FD vs. SOB 3-hr mean averaged from all 15 Best Stations

61. 61 Full-sky LW-NET-LOSS (W/m2) Diurnal Cycle Comparison: FD vs. SOB 3-hr mean averaged from all 15 Best Stations

62. 62 Ta (K) Diurnal Cycle Comparison: FD vs. SOB 3-hr mean averaged from all 15 Best Stations

63. 63 Cloud Fraction Diurnal Cycle Comparison: FD vs. SOB 3-hr mean averaged from all 15 Best Stations

64. 64 VII. SRF LW Comparison: FD vs SRB Statistics for 85-89 Annual-mean Comparison

65. 65 85-89 Annual-mean LW↓: FD - SRB (W/m 2 )

66. 66 85-89 Annual-mean Clear-sky LW↓: FD - SRB (W/m 2 )

67. 67 85-89 Annual-mean LW↑: FD - SRB (W/m 2 )

68. 68 85-89 Annual-mean LW-net: FD - SRB (W/m 2 )

69. 69 85-89 Annual-mean LW-Net Cloud Effects/Forcing: FD - SRB (W/m 2 )

70. 70 VIII. Uncertainties of Ts, Ta and Others and their Caused Global, Daily-mean LW Uncertainties