Christian Kummerow Colorado State University

Chair, GEWEX Radiation Panel

Fourth WCRP Observations and Assimilation Panel (WOAP) MeetingDate: 29-31 March 2009University of Hamburg

GEWEX Radiation Panel Report(Reprocessing)

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1979 1985 1990 1995 2000 2005 2010

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

50 km

100 km

100 km

Available Global Datasets

ISCCP Production Completed thru June 2008

CA=66.4%

PC=573mb

TAU=3.9

TC=261.6K

CALIBRATION EFFECTS

TC

TS

TAU

RS

IR VIS

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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

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

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, LW SW, LW QC

Flux % F0 Flux % F0 Flux % F0 Flux % F0 Flux % F0

SW Down 169.0 49.4 184 53.9 189.2 55.4 188.7 55.2 182.2 53.3

SW Net 142.0 41.6 161 47.2 165.9 48.5 166.6 48.7 159.7 46.7

LW Down 345 100.9 333 97.6 343.8 100.6 343.2 100.4 347.5 101.7

LW Net -40.0 -11.7 -63 -18.5 -49.6 -14.5 -52.8 -15.4 -51.2 -15.0

Total Net 102.0 29.8 98 28.7 116.3 34.0 113.8 33.3 108.5 31.7

SW CRF -- -- -- -- -53.0 -15.5 -58.8 -17.2 -60.9 -17.8

LW CRF -- -- 46 13.5 29.5 8.6 35.3 10.3 34.3 10.0

Total CRF -- -- -- -- -23.5 -6.9 -23.5 -6.9 -26.6 -7.8

Global Multi-Year Averages

S0 = 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)

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SRB Validation and AnalysisSRB Validation and Analysis

Validation AnalysisBSRN 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

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Validation Using BSRN Data (1992-2007)

SW

LW(1992 –

2005)

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

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SRB Reprocessing PlansSRB 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 1ox1o

and/or 1/2o x 1/2o

Assist in DCC technique for calibrationNew error handling

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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)

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Global Precipitation Climatology Project (GPCP)

Adler, Huffman, Gu

Year 2008 Added to GPCP Record—now 30 years

σ/mean

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GPCP developing model for uncertainty

2.64 mm/day ± 9.5%2.12 mm/day ± 7.5%2.87 mm/day ± 10%

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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 periodMonthly (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)ScheduleDelivery 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.

1979 1982 1985 1988 1991 1994 1997 2000 2003 2006 2009 2012

SeaWiFS

MODIS/Terra

MODIS/Aqua

VIIRSNPP/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/OMI

PARASOL

GEWEX Aerosol Climatology Project (GACP)

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

1999 LH flux average

Latent Heat Flux Assessment

Trends in LH Flux (NN Winds)

<carlos.jimenez@obspm.fr> 22

Example of monthly LE fluxes

• Monthly averaged latent fluxes (LE)

August 1993 [W/m2]

1.Introduction

2.Products

3.Examples

4.Annual means

5. Zonal means

6. Basins

7. Summary

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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.

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COMMON DATASETS

• Topography and Land/Water Mask• Ozone• Snow/Ice• Surface Albedo• Surface Emissivity• Atmospheric Temperature and Humidity• TS & SST

• Aerosol Climatology or GACP

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SEA ICE

Datasets Considered: NSIDC Bootstrap, GSFC Bootstrap, NASA Team

Selected GSFC Bootstrap based on probability of existing in future

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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

Sep01 Oct01

TS – ME – TV 2.63 (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 – TV 0.14 (0.69) 0.10 (0.73) cm PW – ME – HIRS -1.48 (1.18) -1.44 (1.18) cm

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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)

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RE-PROCESSING SCHEDULE

Sequencing:Aerosol and Atmosphere ISCCP SRBSeaFlux and LandFlux

-- Atmosphere GPCP

Start in 2010 and Finish in 2011

Process in Reverse Chronological OrderBeginning with 2009