GRWG Microwave Sub-Group Web Meeting
2014-08-26

GSICS Web Meeting on Inter-Calibration of Microwave Imagers

Agenda

1. Cheng-Zhi Zou (NOAA) – Selection of new Chair, 25 min
2. David Walker (NIST):  Update on NIST's Microwave Remote-Sensing Project, 25 min
3. Karsten Fennig (DWD/CMSAF): The Fundamental Climate Data Record of SSM/I Brightness Temperatures from CM SAF, 25 min
4. Rachael Kroodsma (NASA/UMD): GPM Microwave Radiometer Vicarious Cold Calibration, 25 min
5. Isaac Moradi (UMD): Calibrating and Validating ATMS and SAPHIR observations, 25 min
6. Discussion 25 min

Attendees

Guest Chair: Ralph Ferraro

CMA: Qifeng Lu

DWD: Karsten Fennig

EUMETSAT: Tim Hewison, Sreerekha Thonipparambil, Sabatino Di Michele, Vinia Mattioli, Viju John

JMA: Masaya Takahashi

NASA: Rachael Kroodsma

NIST: Dave Walker

NOAA: Cheng-Zhi Zou, Ralph Ferraro, Huan Meng, Weiguo Han, Manik Bali

UMD: Isaac Moradi, Jun Park, Wenze Yang

Summary

Transitioned chairmanship from Cheng-Zhi Zou to Ralph Ferraro (both at NOAA/NESDIS). Kudo's to Cheng-Zhi for a job well done in the past 18 months. Cheng-Zhi has added responsibilities at NOAA since Tsan Mo retired; Ralph has quite of bit experience with passive MW sensors dating back to SMMR and currently with GMI, AMSR-2, SAPHIR, MHS, ATMS, etc. He is honored to take on this position and looks forward to working with everyone!

Moradi - Showed good agreement between ATMS and SAPHIR (for common channels). Also, good agreement with ARM ground measurements, Raobs and GPS RO. Intriguing work on matchup statistics at various time/space scales which could guide future work in this area depending upon accuracy requirements. Also showed impact of geolocation on 183 GHz WV bands.

Walker - A very nice overview of the calibration efforts ongoing at NIST! They are really setting the standards for MW calibration. Most work done to date is in 18 - 65 GHz range, will expand to higher frequencies in the future. Will also explore standards for ocean salinity measurements.

Karsten - Excellent overview of the CM-SAF SSM/I FCDR product. Appears that their methods are more comprehensive, especially over land, than similar products developed by RSS and CSU. Accounting for the proper incidence angle appears to be the critical component to explain these differences. Future work will expand into SSMIS and even back to SMMR. Is this product ripe for a GSICS data product?

Kroodsma - Provided a nice update on the performance of the GPM GMI since its launch in Feb. 2014. Seems like the sensor is performing quite well; noted a few minor issues at 37 GHz related to both yaw and magnetic fields. NASA will reprocess the GMI data in early Sept. (GMI V03B). Also reported on efforts of the GPM X-Cal team - cold calibration, AMSR-2 non-linearities.

Tim Hewison appreciated Isaac Moradi’s comparisons of ATMS with forward-modelled GPSRO stratospheric temperature profiles, noting this activity address an action from the WMO “3G-WIGOS Workshop”. (“ACTION 3G-4: GRUAN and GNSSRO should engage with the GSICS Microwave sub-group to define an activity on inter-comparison of MW instruments especially in areas with no SNOs to test for latitude and day /night dependencies.”) Other members of the Microwave Sub-Group interested in contributing to this activity are invited to contact Tim Hewison and Isaac Moradi.

Outcome

Action:

1. What is needed to move the Calibration Coefficients used to generate the CM-SAF SSM/I FCDR to a GSICS data product and what would a time frame be?
2. Organize a SMMR tiger team to discuss calibration concerns?