1. Joint activities with CEOS/WGCV: Initial progress and example from FY3-MWHS2
Qifeng Lu, Yang Guo, Shengli Wu, Miao Zhang and Dawei AN, Chengli Qi, Mi Liao
National Satellite Meteorological Center ,CMA
Jieying He, Zhenzhan Wang and Xiaolong DONG
Key Laboratory of Microwave Remote Sensing (MiRSLAB),
National Space Science Center (NSSC), Chinese Academy of Sciences
Tim Hewison and Ralph Ferraro
EUMETSAT and NOAA

2. Outline Requirements The communications with CEOS/WGCV
Initial progress
The example from FY-3 MWs, esp. MWHS-2
Next step

3. Requirement for GSICS Microwave: At CGMS-46
Draft list of plenary actions resulting from CGMS-46 discussions (11 June 2018):
WGI actions open from previous plenary sessions (at CGMS-46)
Actionee
AGN item
Action #
Description
Action feedback/
closing document
Deadline
Status
HLPP ref
GSICS F
A46.xx
On passive microwave observations: GSICS is requested to organise an expert meeting on the intercalibration of operational PMW sensors to meet the WIGOS 2040 targets for a coordinated effort to share information on current and future PMW instruments and report to CGMS-47 (CGMS-46-EUM-WP-14)
CGMS-47
OPEN
Joint Meeting between the CEOS/WGCV and GSICS microwave groups:
CEOS/WGCV develop better instrument design strategy and pre-launch calibration algorithms by learning the knowledge of data quality issues and inter- calibration algorithms from GSICS group.  
GSICS develop better re-calibration and inter-calibration algorithms by learning the instrument design and pre-launch calibration issues from the CEOS/WGCV group

4. The communications with CEOS/WGCV
1. the Focus Group Meeting of CEOS WGCV Microwave Sensors Subgroup on August 27, :00pm-5:30pm is mainly on the Calibration/Cross-Calibration of Microwave Scatterometers, but Kurtis Thome, the chair of WGCV, was there. I talked in the last several slides about this cooperation we agreed between the two groups. After that, Curtis Thome responded positively and further he had a personal communication with me on this topic.
2. On 28 AUG Xiaolong Dong presented in the MW Subgroup Report to highlight we agreed to cooperate between WGCV and GRWG on the potential NRT inter-calibration products for microwave imagers and our planed work.
3. In the WGCV-GSICS interactions on 29 AUG, our concept and actions was fully discussed again.

5. Initial progress
Interaction with WGCV-Microwave Subgroup and joint work for Cal/val of passive microwave sensors
Organize a research group in collaboration with WGCV MW group, to identify and confirm the requirement for pre-launch calibration;
Development of techniques for re-calibration/re-processing of historical data.

6. GSICS MW group focuses and WGCV MWSG focuses
Inter-calibration; Data standards
WGCV MWSG focuses supporting GSICS requirements:
Priorities of specific activity areas for interaction with GSICS
Prelaunch calibration for characterization of sensors
Guidelines/standards for prelaunch calibration: specifications, procedures and processing
Postlaunch CAL/VAL for monitoring of calibration parameters, by collaborating with GSICS MW group
Standards toward SI traceability of MW radiometric reference (passive/active noise standards)

7. An draft of ISO International Standard ISO/TC 211 N
Xiaolong Dong leads the MV-subgroup of GEOS/WGCV writing the ISO(the International Organization for Standardization) International Standard document: Calibration and validation of remote sensing imagery sensors – Part 4: Space-borne Passive Microwave radiometers.
Now it is distributed for review and comment.
This Technical Specification standardizes the calibration of remote sensing imagery sensors and the validation of the calibration information and procedures. This part, numbered 4, covers space-borne passive microwave radiometers.

8. The example from cooperative achievement of FY-3
The evolution of FY-3 for NWP
The FY-3A/B/C/D/E Instrument Suites for NWP ok
WindRAD
C ,Ku
HH, VV
Infrared Atmospheric
Sounder (IRAS) 20 channels (~HIRS/3)
HIRAS(1370channels)
Microwave
Temperature
Sounder (MWTS)
4 channel (~MSU)
13 channels
17 channels
Microwave
Radiation Imager
10 channels
(~AMSR-E)
Microwave
Humidity
Sounder (MWHS)
5 channel (~MHS)
15channels with channels at
118 GHz
GNSS
Radio-Occultation
Sounder (GNOS)
(~GPS) 8 8 8 8

9. The progress of FY-3 data in NWP
FY-3B MWHS
FY-3C MWTS2
FY-3C MWHS2
FY-3C MWRI
FY-3C IRAS
FY-3C GNOS
ECMWF
Op DA
Evaluation
Now dead
Monitoring
UKMO
CMA NWPC
FY3C MWHS-2 has been operationally assimilated and monitored in the Met Office global model on 15 March 2016, and in ECMWF IFS system on 4 April
Operational assimilation of MWHS-2 with 183 GHz channels globally and GNOS in CMA/GRAPES have been activated in April 2016.
The transmittance of bufrized data by GTS started since 2017.
The GNOS wad operationally assimilated by ECMWF since March 2018.
The FY-4A and FY-3D data have been cooperatively evaluated by CMA and ECMWF, UKMO etc. The CMA/NWPC has operationally assimilated the FY-4A GIIRS in DEC 2018.
The recent teleCON was held in Jan 2019 to exchange the experience from FY3D and FY-4A

10. The NeDT of FY-A/B/C/D MWRI

11. The MWTS-2 NeDT Calibration accuracy （O-B） 1.46 0.6 -0.15 -0.33 -0.857 8 9 10 11 12 13
BAIS(k)
1.46
0.6
-0.15
-0.33
-0.85
-0.73
-0.99
-0.3
0.32
0.67
3.26
4.35
6.15
STD(k)
7.85
4.75
2.09
0.86
0.68
0.45
0.55
0.53
0.63
0.92
1.24
1.27
2.08
Calibration accuracy （ATMS Cross comparison ） 1 2 3 4 5 6 7 8 9 10 11 12 13
BAIS(k)
-0.36
-0.65
-0.29
-0.17
-0.92
-0.57
-0.41
-0.11
-0.1
0.66
0.3
-0.2
STD(k)
0.65
0.5
0.4
0.22
0.23
0.32
0.44
0.46
0.82
0.85 11 11 11

12. The GNOS :Daily Occ. Number and Stopping Height
从每日掩星数量的统计来看，D星GPS掩星数量比C星增加了5%-10%，D星北斗的数量比C星北斗增加了100%，得益于D星通道数增加，以及D星上对北斗信号的开环接收（open-loop tracking），即仪器的改进使得日掩星数量增多；
下面两张图是掩星廓线能够探测到的最低深度，在不同高度的比例。GNOS GPS 有80%的廓线能够在5km以下，下降掩星占比可达90%以上。
Data used from 1st July to 15th July,2018

13. The HIRAS FY3D HIRAS On-orbit status shows good performance HIRAS-CrIS
HIRAS-IASI
HIRAS compared to CrIS and IASI：LW bias less than 0.5K，MW1 about 0.7K；MW2 in range of 1K。

14. FY-3D/HIRAS on orbit NEdT monitoring @ LW 720cm-1,
Spectral bias compared with Line-by-line simulation
O-B monitoring
Spectral bias less than 5ppm for 3 bands of 12 FOVs，LW/MW1 Std less than 2ppm.
O-B monitoring shows stable error characteristics.

15. The Example from FY3-MWHS2
Calibration Method
Bandwidth Correction
Due to：
Obvious difference between the actual band and calculating band of the channels of MWHTS
The bands of MWHTS are too broad to meet the criterion of monochromatic light
So：
Firstly, integrated the radiation in the actual passband of MWHTS and the ideal rectangle passband respectively to get the Bandwidth correction coefficients,b0 and b1.
Secondly, use formula:

16. 2.Two-point Calibration
Calibration Method
2.Two-point Calibration
Use hot target’s radiance( ),cold target’s radiance( ),Earth target’s radiance( ) , the average voltage of hot target( )and the average voltage of cold target( ) with the following formulas to set up the two-point calibration equation.

17. 3. Cold and hot calibration bias correction.
Calibration Method
3. Cold and hot calibration bias correction.

18. 4. Analysis of system nonlinearity.
Calibration Method
4. Analysis of system nonlinearity.
Use system nonlinear coefficient (u) to describe the system nonlinearity after hot and cold calibration target bias correction.

19. Rotating and lifting platform
T/V Plan of MWHS-2
Earth target
1、Position 1:
point5（pixel49） Earth target
point9（pixel1） Cold target
2、Position 2:
point4（pixel12） Earth target
point8（pixel61） Cold target
3、Position 3:
point3（pixel73） Earth target
point7（pixel25） Cold target
4、Position 4:
point2（pixel85） Earth target
point6（pixel37） Cold target
5、Position 5:
point1（pixel97） Earth target
point5（pixel49） Cold target
6、Position 6:
point11（pixel32） Earth target
point10（The Cold sky） Cold target 9 1 2 3 4 5 6 7 8 10 11
Cold
target
Rotating and lifting platform
MWHS
-II
Hot target
Observation positions in T/V calibration

20. T/V Test Process of MWHS-25℃
15℃
15℃
25℃
1、5℃：
Step of Earth target：15K
Observation position：6
2、15℃：
Step of Earth target ：10K
(Falling)
Observation positions：1-6
3、15℃：
(Rising)
4、25℃：
Step of Earth target ：15K

21. Calibration Method and Data Analysis
Instrument Stability Analysis
Hot, Cold, Earth Targets’ Stabilities Analysis
Sample Position Analysis
Changing of IF temperature shows the stability of MWHS-II
Changing of IF Temperature

22. Stability Analysis of Hot target
89/118
150/183
There is no heat insulation to the hot targets. So the 89/118GHz hot target which is near the heating area is influenced by the temperature variation of the instrument temperature and the ambient temperature. However, the 150/183GHz is relatively stable for its longer distant from the heating area compared to that of the 89/118GHz target.
89/118
△T<1.2K
150/183
△T<0.8K

23. Hot, Cold, Earth Targets’ Stabilities Analysis
Hot target: Occasionally little jump
Cold target:PRT-6 differs from the others
Earth target:
Cold Target:
Earth target:
Cold Target:
Jump of one of the PRTs
Interferences in the PRTs

24. Sample Position Analysis1 2 3 4 5 6
Cold target
5-8
10-16
22-28
36-38
43-45
Cold space
Earth target
45-55
60-63
70-76
84-86
90-94
30-35

25. The FY-3D MWHS-2 of NeDT FY-3C NedT FY-3D NedT Requirement NEDT
Channels

26. after cloud screening, ocean +/- 45 latitude
The FY-3D MWHS-2 of O-B
FY-3D
FY3D-CRTM FY3D-RTTOV FY3D-CRTM（FNL） Specification
FY-3C
FY3C-CRTM FY3C-RTTOV Specification
2018/3/21-25
after cloud screening, ocean +/- 45 latitude

27. FY-3D MWHS-2 O-B Time series Monitoring

28. Next Step
Organize a joint research group to improve the instrumental characterization, calibration/validation and its application in NWP and reanalysis, hopefully we would have the guys from WGCV, GSCIS and NWP/Reanalysis working together and feedback smoothly
Standardize the calibration procedure and the SI traceability of MW radiometric reference
Optimize the instrument design strategy and pre-launch calibration algorithm
Develop the techniques for re-calibration/re-processing of historical data
Monitor the instrumental performance by the difference of the intersatellites and the OMB from NWP fields
Normalize the output from GSICS MW-subgroup as an important component of WIGOS