1. GRWG/GDWG Joint Web Meeting Agenda
Review of Agenda
Approval of Minutes
Discussion of ATBD
Harmonization – in coordination with GPRCs
Focus on GSICS Correction
Harmonization – in coordination with GDWG
File and variable name
Archive strategy
Suggestions/Discussions
Review of Actions
Any Other Business
Next Meeting
Date and Time
Key issues
Meeting Adjourned
2 Jun 2009
Joint GRWG/GDWG Web Meeting

2. Joint GRWG/GDWG Web Meeting
Approval of Minutes
Web meeting on 26 Mar 2009
Minutes drafted 2 Apr 2009
Discussion continued till 14 Apr 2009
Revised accordingly and distributed
Special meeting on 12 May 2009
Move to approve both minutes
2 Jun 2009
Joint GRWG/GDWG Web Meeting

3. Joint GRWG/GDWG Web Meeting
ATBD Issues (1 of 4)
Y. Tahara suggested Tb-based GSICS Correction
JMA and CMA disseminate scaled Tb, unlike EUMETSAT and NOAA who disseminate scaled radiance
It was later confirmed that the scaled Tb can be converted to radiance easily without invoking Planck’s function and spectral response function etc.
GRWG recommends harmonized products when possible
JMA agreed on radiance-based GSICS Correction
2 Jun 2009
Joint GRWG/GDWG Web Meeting

4. Joint GRWG/GDWG Web Meeting
ATBD Issues (2 of 4)
Y. Tahara and A. Okuyama suggested alternative regression to properly account for LEO uncertainty
GRWG welcomes the suggestion
GPRCs are encouraged to further study this and other options
GPRCs are free to select the option optimal for their applications, however the advantage of the choice should be documented.
2 Jun 2009
Joint GRWG/GDWG Web Meeting

5. Joint GRWG/GDWG Web Meeting
ATBD Issues (3 of 4)
X. Wu suggested amending the GSICS data flow with “Products” at the end
A collection of GSICS products, extracted or derived from Statistical and other data, to serve as interface with users.
R. Iacovazzi amended that all and only Products should be subject to GSICS Approval
M. König and T. Hewison amended that initial product should be GSICS Correction (formula and coefficients) only
Other useful information, such as bias before and after correction, can be added later
No consensus yet
No change at present
May be discussed in future if relevant
2 Jun 2009
Joint GRWG/GDWG Web Meeting

6. Joint GRWG/GDWG Web Meeting
ATBD Issues (4 of 4)
X. Wu suggested each ATBD be focused on a particular GEO-LEO pair
Current structure requires recommending one option for a class
Sometimes trivial, e.g., gap filling scheme for IASI-based algorithm
Sometimes difficult, e.g., collocation for GPRCs with and without specialized information (orbit pointing) and software (McIDAS).
No consensus yet
No change at present
With EUMETSAT ATBD as example, GPRCs should be able to handle
May be discussed in future if relevant
2 Jun 2009
Joint GRWG/GDWG Web Meeting

7. Joint GRWG/GDWG Web Meeting
ATBD Issues
Any others?
2 Jun 2009
Joint GRWG/GDWG Web Meeting

8. Harmonization Among GPRCs
Focus on GSICS Correction formula and coefficients only
Following is status at NOAA, using the simplest case (GOES m channel) as example to explore the path
Open to comments
2 Jun 2009
Joint GRWG/GDWG Web Meeting

9. GSICS Correction Status at NOAA
Regression:
RGEO = slope * RLEO + intercept
RGEO & RLEO: radiance from GEO & LEO
Slope and intercept: regression coefficients, weighted with stdv_env
Indication of nonlinearity will be investigated further
2 Jun 2009
Joint GRWG/GDWG Web Meeting

10. GSICS Correction Status at NOAA
Smoothing – Theoretical basis:
GEO bias can vary slowly (seasonal and beyond) in unknown fashion
Smoothing period should be reasonably short to catch this variation
GEO bias can also vary diurnally
Particularly for 3-axis stabilized platforms
Will be investigated separately
GEO bias does not vary day-to-day (absent of special event)
Smoothing period should be reasonably long (more than one day) to smooth out regression uncertainty
Two ways of smoothing
Running average of regression results from daily collocations
Running period of regression
2 Jun 2009
Joint GRWG/GDWG Web Meeting

11. GSICS Correction Status at NOAA
GSICS Corrected GEO Radiance
RGSICS = 1/slope * RGEO - intercept/slope
Amount of Correction
Correction = RGSICS - RGEO
2 Jun 2009
Joint GRWG/GDWG Web Meeting

12. Recursive Regression to Identify and Remove Outliers
Time period: (5 days)
Daytime
Linear regression weighted with inverse of FOV std radiance
unfiltered
filtered
Outliers
Systematic under-estimate of GOES-11 radiance at both low and high ends – nonlinearity?
2 Jun 2009
Joint GRWG/GDWG Web Meeting

13. Joint GRWG/GDWG Web Meeting
Running average = 5 days
Regression period = 10 days
GEO – LEO azimuth < 40 degree
Daytime collocation
Over the Ocean collocation
Otherwise, all the collocation pixels used
Running average = 5 days, Regression period = 10 days, GEO – LEO azimuth < 40 degree, Daytime collocations over ocean. No recursive regression.
2 Jun 2009
Joint GRWG/GDWG Web Meeting

14. Joint GRWG/GDWG Web Meeting
Running average = 5 days
Regression period = 15 days
GEO – LEO azimuth < 40 degree
Daytime collocation
Over the Ocean collocation
Otherwise, all the collocation pixels used
2 Jun 2009
Joint GRWG/GDWG Web Meeting

15. Joint GRWG/GDWG Web Meeting
2-D Distribution of GSICS radiance correction for GOES11 channel 10.7um
Running average = 1
Regression period = 10
Running average = 1
Regression period = 30
Running average = 5
Regression period = 10
Running average = 5
Regression period = 30
This slide confirms that regression period is the dominant factor to smooth the daily GSICS correction
2 Jun 2009
Joint GRWG/GDWG Web Meeting

16. Joint GRWG/GDWG Web Meeting
2-D Distribution of GSICS radiance correction for GOES11 channel 10.7um
Running average = 5 days
Regression period = 30 days
Strong seasonal variations for the cold scenes
Significant warming correction trend for the warm scenes
Larger correction for the cold scenes than the warm scene
2 Jun 2009
Joint GRWG/GDWG Web Meeting

17. Joint GRWG/GDWG Web Meeting
2-D Distribution of GSICS radiance correction for GOES11 channel 10.7um
Running average = 5 days
Regression period = 60 days
2 Jun 2009
Joint GRWG/GDWG Web Meeting

18. Joint GRWG/GDWG Web Meeting
2-D Distribution of GSICS radiance correction for GOES11 channel 10.7um
Running average = 5 days
Regression period = 90 days
2 Jun 2009
Joint GRWG/GDWG Web Meeting

19. GSICS Correction Status at NOAA
Discussions:
2 Jun 2009
Joint GRWG/GDWG Web Meeting

20. Harmonization with GDWG
File and variable name
Archive strategy
Suggestions/Discussions
2 Jun 2009
Joint GRWG/GDWG Web Meeting

21. Joint GRWG/GDWG Web Meeting
Review Actions 30 Jan 2009
Members shall carry out the modified GSICS 2009 Operation Plan by December 2009
All GPRCs shall prepare its ATBD, to be reviewed at the web meeting in May 2009 and submitted to GCC by June NOAA shall distribute its ATBD before the web meeting in March 2009.
All GPRCs shall routinely produce the GSICS Correction for its GEO by March 2009, with its choice of algorithm and format for the product.
The documentation and harmonization of the GSICS Correction shall be discussed at the March and May web meetings. The initial release shall occur by June 2009.
NOAA GPRC shall produce GSICS Correction for all GEOs by March 2009, using a common baseline algorithm to facilitate algorithm comparison and improvement.
All GPRCs shall evaluate the Product Acceptance Procedure with the LEO-LEO products and a GSICS product of its choice, and provide feedback on scientific criteria to be met by GSICS products by June 2009.
B. J. Sohn shall coordinate with CMA, JMA, KMA, NOAA, and NASA to identify the targets by June 2009.
F. Wu shall coordinate a review of GSICS Implementation Plan by December 2009.
Color code: Complete / On Schedule / Delayed / Need Revision
2 Jun 2009
Joint GRWG/GDWG Web Meeting

22. Review Actions – Web Meetings
All participants to upload the presentations by Friday prior to the meeting (May 2009).
JMA to prepare a report on the difference between AIRS and IASI they recently characterized (June 2009).
JMA to inform GSICS EP (through Secretariat J. Lafueille) of the personnel change (CLOSED).
CMA to inform GSICS EP (through Secretariat J. Lafueille) of the personnel change (CLOSED).
KMA to distribute a detailed description of selecting additional sites for SADE (CLOSED).
EUMETSAT and NOAA to submit complete ATBD, defined in a hierarchical structure following T Hewison's example.
2 Jun 2009
Joint GRWG/GDWG Web Meeting

23. Joint GRWG/GDWG Web Meeting
Any Other Business
Suggestions?
2 Jun 2009
Joint GRWG/GDWG Web Meeting

24. Joint GRWG/GDWG Web Meeting
Next Meeting
Date and time
Key issues
Meeting Adjourned
2 Jun 2009
Joint GRWG/GDWG Web Meeting