Planning GSICS MW Products

1100 UTC on Tues July 25 ,2017

The dial in number to use is:

US - 1-888-396-1320
Passcode - 9371952
International - 1-517-966-4753

Introduction

The purpose of this meeting is to discuss the kind of GSICS products should the Microwave Subgroup deliver. A small splinter group was formed to begin the initial discussions, once details are made more mature, it will be shared with the broader MW subgroup at a future meeting. It follows from two actions that were generated in the GSICS Annual Meeting -2017 in Madison, Wisconsin.

A.GMW.2017.6c.1: Determine feasibility of extracting the inter-calibration algorithms and coefficients from the FCDR and making them a GSICS product - Lead: Fennig Karsten [This is for a MW window channel/imager product]

A.GMW.2017.6d.1: Determine feasibility of extracting the inter-calibration algorithms and coefficients from the FCDR and making them a GSICS product.-Lead : Cheng-Zhi Zou [This is for a MW oxygen channel/sounder product]

Those in attendance included - Ralph Ferraro, Cheng-Zhi Zou, Manik Bali, Karsten Fennig, Masaya Takahashi.

Summary

Manik lead the discussion with a nice presentation of the tasks at hand and path forward (see his slides attached).

Some of the key topics we discussed included:
  • Classical GSICS products - mostly slopes and offsets applied to counts, updated routinely for operational sensors, information provided via ICVS, etc.
  • FCDR GSICS products - are these acceptable or not? Maybe it's the best practices from these that are most relevant to GSICS (e.g., SNO, use of RTM, etc.)
  • Should we revisit the User Survey from a few years ago, refine the questions, and get a broader response? That would help us determine what are the highest priority paths we should pursue
  • Ralph would like to see us develop something for GSICS from these two mature, FCDR's. Maybe it is simply best practices? But we certainly do not want to put extra burden on the CDR developers.

Some of the critical comments by the data sets/best practices under consideration:
  • Cheng-Zhi: Methods he employed are not necessarily the best for the classical GSICS products, which require routine updating (i.e., monthly) which are impractical for the CDR data sets.
  • Karsten: There could be a good synergy between the SCOPE-CM FCDR's and the goals of GSICS in terms of fulfilling user needs and moving towards some commonality of the data sets themselves (i.e., naming convention, desired parameters, etc.). This could be a logical path forward in future releases of the FCDR's
Masaya further captured some of the essential aspects of the discussion and items for this focus group to consider as we attempt to move forward:
  • Making FCDR a GSICS product

As Cheng-Zhi mentioned, GSICS Executive Panel decided that FCDR is not GSICS inter-calibration product. Firstly, I would like to ask you to take a look of the meeting minutes on this issue:
GSICS-EP-16 (2015): page#6 (just before agenda#6) of http://www.wmo.int/pages/prog/sat/documents/GSICS-EP-16_Final-Report.pdf
 
Why generating FCDR is not within the scope of the GSICS? For example, the following action was assigned to the member agencies:Agencies to consider implementing the near real time distribution of boththe operational calibration information and the corrected calibration information, as part of the L1 data formats. "The corrected calibration information" represents GSICS inter-calibration information. On the other hand, "generating Level-1 data" is not within the scope the GSICS. I think GSICS-EP's opinion on the FCDR is similar to this concept because FCDR is also Level-1 product.
 
Another example is a relationship between GSICS and SCOPE-CM. As you may have seen the conceptual framework of SCOPE-CM project (http://www.scope-cm.org/), FCDR/TCDR are generated within the SCOPE-CM by ingesting GSICS inter-calibration (radiance correction) information. However, I agree with your opinion to discuss this issue with GSICS-EPagain if the MW Sub-group really needs.
 
  • Classical GSICS products
As I commented, there is no limitation on the inter-calibration approach for the Classical products. Only limitation is the Classical products are the radiance correction information, not corrected radiance (Level-1) data. If we could provide the correction information as a function of scan angle or geolocation, such information could be acceptable for the Classical products. Adding on-board health information or link to ICVS (pointed on Manik's slide#10) is very good idea and this is also acceptable - we could include such information in the Global Attributes of the netCDF file.
 

Summary of GCC view on MW Product

The goal of GSICS is intercalibration of instrument measurements. This can range from retrospective to near-real-time. Whatever aspects of instrument performance/characterization affect the measurements or their use are appropriate parameters including, for example, wavelength scales, bandpasses/SRFs, response non-linearity and stray light as well as the usual biases and offsets.

GCC on Acceptance of Product in GSICS via GPPA

GCC uses the tenants of GPPA to accept and assign maturity to the product. The interaction between the product and the users is a vital aspect of GPPA and the feedback provided by users help evolve the product and eventually helps in assigning maturity to the product. In the light of this we reccomend the following actions on the producers prior to the daily production of the product
  1. Letter of support from agency management on the creation of the product.
  2. Benifit of using the product ( say impact report along the lines stated here)
In the past GCC has collected user requirements ( via questionares and evaluating FIDUCEO )and summarized them. It is reccommended that producers of MW product consider these summaries to help understand the need of the MW community to connect their products better with the users.




GCC Strawman User Requirements’ document 7b
GCC User Survey 7c
Also on the point Larry has indicated on Real Time and Re-Analysis, GCC has the following feedback from the GSICS Community that producers can consider. This is simmarized here . Beyond these feedbacks that were collected in the recent past, GCC is happy to take actions (GMW.20170725.1) to understand better the user needs and provide these to the potential producers of the MW product.

Microwave products can encompass the following information

  • Typically products are accompanied with documents. These document provide detail desription of the product, User guide and uncertainity analysis.
    1. Inter-Calibration aspect ( for eg ATMS- FCDR inter-Cal or SSMI-FCDR)
    2. Onboard health encoding (For e.g ICVS)
    3. Strong Metadata providing links to monitored instrument and the reference instrument data sets
    4. User Guides ATBD
    5. Quality Flags, Uncertainity estimates

Actions

  • A.GMW.20170725.1:Reformulate the MW Questionnaire and distribute to a broader user base, including all GSICS members. Ralph and Manik will draft the next set of questions and distribute to this group for commenting
  • A.GMW.20170725.2:Can we define short-term and long-term goals? Short term would be what we could accomplish within the next year - seems like "best practices" might be something to strongly consider. Cheng-Zhi and Karsten to think more closely about their products/practices and define some starting points.
  • A.GMW.20170725.3:Group to meet again in September time-frame (but prior to next full MW subgroup meeting so we can present out findings) Ralph will organize this.
Topic revision: r8 - 29 Jul 2017, ManikBali
This site is powered by FoswikiCopyright © by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding GSICS Wiki? Send feedback