1 Data Impact Experiments at the JCSDA and NCEP/EMC S. Lord (NCEP/EMC) L.P. Riishojgaard (JCSDA) Contributions by: L. Cucurull, J. Jung, L. Bi, D. Kleist, B. Yan, I. Appel, D. Stokes

2 Overview Impact experiments for: –COSMIC –QuikSCAT & Windsat –MODIS winds –IASI –SSM/IS –ASCAT Summary and comments

3 COSMIC Data Impact No COSMIC With COSMIC 1 Nov 2006 to 30 Nov 2006 Refractivity assimilated variable ~1000 profiles assimilated per day Tropics 200 hPa RMS Wind Error 48 h NH 500 hPa Height Anom. Cor.SH 500 hPa Height Anom. Cor. 0.1 m/s improvement L. Cucurull

4 QuikSCAT Impact on Standard Verification Scores Operational GFS (T382/L64), GSI with FOTO –Control (operational QuikSCAT) –Q denial (no QuikSCAT) –Q new (FY07 improved retrievals) 5 July to October 2005 (~4 months) NH 1000 hPa Height RMS ErrorSH 1000 hPa Height RMS Error Similar results obtained for 2006 cases D. Kleist

5 Windsat Impact on Standard Verification Scores Operational GFS (T382/L64), GSI with FOTO –Control (operational QuikSCAT) –Ws included (with QuikSCAT) –Ws only (no QuikSCAT) –No Ws, no Qs 25 April 2007 to 8 June 2007 (~1.5 months) SH 1000 hPa Height RMS ErrorNH 1000 hPa Height RMS Error D. Kleist

6 QuikSCAT Impact on Tropical Cyclone Forecasts 2004 Study Jung and Zapotocny JCSDA

7 QuikSCAT Impact on Tropical Cyclone Forecasts (cont) Climatology-persistence No QuikSCAT New QuikSCAT Track Error Atlantic &12 UTC 65 cases18 cases D. Kleist D. Stokes

8 Impact of MODIS winds on GFS 500 hPa Anomaly Correlation I. Appel NH February SH February NH July SH July

9 IASI Impact Tests First attempt to use data at JCSDA/NCEP(EMC) Channel selection: EUMETSAT longwave only 30 day spinup for bias correction Experiment and control use same initial bias corrections Scores averaged over last 30 days –1-31 August 2007 –16 December January 2008

10 IASI Impact on Standard Verification Scores NH 500 hPa Height Anom. Cor August 2007 SH 500 hPa Height Anom. Cor. J. Jung IASI Control

11 IASI Impact on Standard Verification Scores NH 500 hPa Height Anom. Cor. 16 December December 2008 SH 500 hPa Height Anom. Cor. J. Jung IASI Control

12 SSM/IS Impact Summary  Positive impacts of SSMIS UPP data can be obtained through improved cloud detection, surface snow and sea ice emissivity simulations  A positive impact of SSMIS UPP data is anticipated by adding water vapor channels (not shown)  The SSMIS UPP data displays some regionally dependent biases at several sounding channels which would reduce their assimilation impact (not shown)

13 Improved snow and sea ice emissivity Improved SSM/IS forecast impact due to science & processing upgrades Improved cloud detection & QC CTL EXP Cloud detection & QC EXP CTL Alternate processing B. Yan et al

14 ASCAT Impact Tests First results at JCSDA/NCEP(EMC) 10 December 2007 – 19 January 2008 Thinned to 100 km Quality Control: –Ocean only (from GDAS land-sea flag) –Reject observation if O-B > 5m/s (U and V) Li Bi & J. Jung NH 1000 hPa Height Anom. Cor.SH 1000 hPa Height Anom. Cor. ASCAT Control

15 ASCAT Impact Tests First results at JCSDA/NCEP(EMC) 10 July 2007 – 17 August 200 Thinned to 100 km Quality Control: –Ocean only (from GDAS land-sea flag) –Reject observation if O-B > 5m/s (U and V) Li Bi & J. Jung NH 1000 hPa Height Anom. Cor.SH 1000 hPa Height Anom. Cor. ASCAT Control

16 Summary & Comments Impacts measures by standard scores for –COSMIC –QuikSCAT & Windsat –MODIS winds –IASI –SSM/IS –ASCAT JCSDA and NCEP experience –Spin up of global system takes ~6 weeks to produce reliable obs. sensitivity signal –Coarse resolution results not representative of those at resolutions higher than ~50 km globally –Use of downstream models and applications could be useful to determine impacts Hurricanes Waves Impact depends on improvements to science (e.g. SSM/IS) –Surface emissivity (MW and IR) –Bias correction –Cloud detection

17 Summary & Comments (cont) Impact experiments are resource intensive –Many take place in the course of the operational implementation process and are necessary –Many custom experiments generally beyond our means Respond to HQ requests for special programs (e.g. QuikSCAT) –Could (and should) be done annually with proper support (e.g. instrument programs) Would pay dividends in –Focusing scientific development –Providing feedback for future instrument programs –Keeping entire community engaged in the total investment A complementary OSSE program would be a very useful addition

18 Backup Slides

19 SATELLITE DATA STATUS – May 2008 Jason AltimeterImplemented into NCEP GODAS AIRS with All Fields of ViewImplemented – 1 May MODIS WindsImplemented– 1 May NOAA-18 AMSU-AImplemented– 1 May NOAA-18 MHSImplemented– 1 May NOAA-17 SBUV Total Ozone4 December 2007 NOAA-17 SBUV Ozone ProfileImplemented– ??? SSMI/S RadiancesPreliminary forecast assessment completed GOES 1x1 sounder radiancesImplemented 29 May 2007 METOP AMSU-A, MHS, HIRSImplemented 29 May 2007 COSMIC/CHAMP Implemented (COSMIC – 1 May) CHAMP Data in prep. MODIS Winds v2.Test and Development WINDSATPreliminary forecast assessment completed AMSR/E RadiancesPreliminary forecast assessment completed AIRS/MODIS Sounding Channels Assim.Data in Preparation JMA high resolution windsImplemented 4 December 2007 GOES Hourly Winds, SW WindsTo be Tested GOES 11 and 12 Clear Sky Rad. Assim(6.7µm)To be Tested MTSAT 1R Wind Assim.Data in Preparation AURA OMITest and Development TOPEX,ERS-2 ENVISAT ALTIMETERTest and Development (Envisat) ERS-2 (dead) TOPEX implemented in NCEP GODAS FY – 2CData in Preparation

20 Jung and Zapotocny JCSDA Funded by NPOESS IPO Satellite data ~ 10-15% impact

21 Operational data assimilation at NCEP Lidia Cucurull Joint Center for Satellite Data Assimilation COSMIC IWG Meeting, New Orleans, LA, Jan

22 The JCSDA developed, tested and incorporated into the new generation of NCEP’s Global Data Assimilation System the necessary components to assimilate two different type of GPS RO observations (refractivity and bending angle). These components include: –complex forward models to simulate the observations (refractivity and bending angles) from analysis variables and associated tangent linear and adjoint models –Quality control algorithms & error characterization models –Data handling and decoding procedures –Verification and impact evaluation algorithms Pre-operational implementation runs showed a positive impact in model skill when COSMIC profiles were assimilated on top of the conventional/satellite observations. As a result, COSMIC became operationally assimilated at NCEP on May 1st 2007, along with the implementation of the new NCEP’s Global Data Assimilation System (GSI/GFS). [Profiles of refractivity were selected for implementation in operations, while the tuning of the assimilation of bending angles is currently being analyzed at NCEP]. The assimilation of observations from the COSMIC mission into the NCEP’s operational system has been a significant achievement of the JCSDA. [Operational assimilation one year after launch!]. Achievements at the JCSDA

23 Characteristics of COSMIC observations Limb sounding geometry complementary to ground and space nadir viewing instruments –High vertical resolution (0.1 km surface - 1km tropopause) –Lower horizontal resolution (~300 km) All weather-minimally affected by aerosols, clouds or precipitation High accuracy (equivalent to < 1 Kelvin from km) Equivalent accuracy over ocean than over land Independent of radiosonde calibration No instrument drift Global coverage No satellite-to-satellite observational bias Inexpensive compared to other sensors

24 Characteristics of COSMIC observations Average COSMIC counts/day at NCEP (2007) We assimilate rising and setting occultations, there is no black-listing of the low-level observations (provided they pass the quality control checks), and we do not assimilate observations above 30 km (due to model limitations). In an occultation, the drift of the tangent point is considered. The remaining ~30% received, but not assimilated, is due to: –Preliminary quality control checks (bad data/format) –Gross error check (obs very different from the model) –Statistics quality control check (obs too different from the model-obs statistics)

25 Pre-operational implementation run PRYnc (assimilation of operational obs ), PRYc (PRYnc + COSMIC refractivity) We assimilated around 1,000 COSMIC profiles per day Anomaly correlation as a function of forecast day (geopotential height) rms error (wind)

26 Dashed lines: PRYnc Solid lines: PRYc (with COSMIC) Red: 6-hour forecast Black: analysis Pre-operational implementation run (cont)

27 Summary and future plans COSMIC (refractivity) became operationally assimilated at NCEP on May 1st 2007, along with the implementation of the new NCEP’s Global Data Assimilation System (GSI/GFS). Several impact studies for selected periods show a positive impact in model skill when COSMIC profiles are assimilated on top of the conventional/satellite observations. [We have recently improved the assimilation of GPSRO profiles over complex topography.] what is next? Testing, tuning and assimilation of GSPRO from CHAMP & GRACE (in pre-operational mode; March 2008) and MetOp/A GRAS (when available). Setup the monitoring of GPSRO statistics in operations (May 2008). Update QC checks and obs error for COSMIC data (June 2008). Assimilation of COSMIC observations (and other GPSRO missions) into the regional model (July 2008). Improve the performance of the assimilation of observations of bending angle (November 2008; switch to bending angle in operations?). Explore more complex forward operators to take into account horizontal gradients of refractivity (??).

28 Time series of day-5 scores

29 Five-day forecast minus verifying analysis. February 23, 2007, 00z Control Control + MODIS IR

30 Impact of Improved Snow and Sea Ice Emissivity at SSMIS Channels on F16 UPP SSMIS Data Usage New SNOW EM New Ice EM Old EM More data is assimilated Into GFS !

31 A positive impact of SSMIS UPP data at water vapor sounding channels is detected on GFS. (July 1 ~ July 10, 2007)