1. CMA Working Papers for CGMS-42
China Meteorological Administration
National Satellite Meteorological Center
Training Course on Satellite Meteorology 2012 ）Oct.22-Nov.2 Beijing China

2. List of CMA Working Papers for CGMS-42 Workgroup II
Agenda Item
CMA-WP
CMA progress on AMV inter-comparison study
CMA Feedback on GHRSST Data Specification
Progress of CMA in GSICS Activities
Project for Inter-calibration of Long-term Data Set of FY-2 Imager Observations ( IOGEO）

3. CMA Feedback on GHRSST Data Specification
The CMA-WP-08 informs that the global Sea Surface Temperature (SST) related products are derived operationally at the National Satellite Meteorological Center of China Meteorological Administration (NSMC/CMA) using the Visible and Infrared Radiometer (VIRR) onboard the FY-3 satellite. The CMA making global SST L2 and L3 products. This paper introduces the CMA SST data products specification and its file naming convention. The CMA SST products specification is crosschecked with GHRSST data specification(GDS).

4. Overview of CMA Global SST
Daytime
Nighttime
5minutes granule SST：1KM L2
Daily globe SST： KM L2
Ten-days globe SST： 5KM L3
Monthly globe SST： 5KM L3 Da i l y
5minutes granule daytime SST( :15 UTC)
5minutes granule nighttime SST( :30 UTC )
Ten
-days M o n t h l y
2014年1月31日全球旬平均

5. CMA SST data products specification
SST Product
Level 2
Level 3
Acronym L2 L3
Description
Geophysical variables derived from Level 1 source data at the same resolution and location as the Level 1 data, typically in a satellite projection. Geographic information saved in other file.    No adjustments to input SST have been made.
L2 data granules remapped to a space grid.SST measurements combined from a single instrument into a space-daily grid. Multiple passes/scenes of data can be combined. No adjustments to input SST have been made.
SST measurements combined from a single instrument into a space-time grid. The timescale include ten-days and monthly. Multiple passes/scenes of data can be combined.   No adjustments to input SST have been made.
Grid specification
Native to SST data format
Defined by data provider
Temporal resolution
Native to SST data stream
Delivery timescale
As available, Ideally within 3 hours from acquisition at satellite
Target accuracy
Native to data stream
Error statistics
Coverage
globe coverage
In accordance with the requirements of the study, two datasets were utilized to derive AMVs.
The filenaming convention for CMA SST data products is shown below.<Satellite Platform>_< Satellite Sensor>_<Coverage Code>_<Processing Level>_<Product Code>_<Channel Number>_<Projection Code>_<Indicative Date>_<Indicative Time>_<Resolution>_<Receive Station>.<File Type>

6. CMA SST product file naming convention components.
Name
Definition
Description
<Satellite Platform>
FY3C
The satellite platform code(FY3A,FY3B,FY3C etc).
< Satellite Sensor>
VIRRX
The satellite sensor code. VIRR: Visible and Infrared RadiometerX:D or N D: Day N: Night
<Coverage Code>
ORBT GBAL
The data coverage code. ORBT: orbital granuleGBAL: globe coverage
<Processing Level>
L2L3
The data processing level code (L2 or L3)
<Product Code>
SST
The satellite product code(SST,OLR,etc.).
<Channel Number>
CHnMLT
The channel number of data derived from.CHn: channel n. MLT: multi-Channel.
<Projection Code>
NULGLL
The data projection method. NUL: satellite projectionGLL: Geographic Lat/Lon
<Indicative Date>
YYYYMMDD
The identifying date for this data set.
<Indicative Time>
HHMMPOADAOTDAOAM
The identifying time for this data set. The time used is dependent on the <Processing Level> of the data set:HHMM: start time of granulePOAD: product of a dayAOTD: avarge of ten-daysAOAM: avarge of a month
<Resolution>
1000M5000M
The resolution of the data. 1000M: 1 kilometer,5000M: 5 kilometer
<Receive Station> MS
Indicates data is received from multiple stations MS: multiple stations
<File Type>
HDF
Indicates this is a HDF file containing data

7. Filename by Example L2_SST:
FY3C_VIRRD_ORBT_L2_SST_MLT_NUL_ _0215_1000M_MS.HDF
CMA daytime L2 skin SST data for 05 January 2014, from VIRR multiple stations data collected from the FY-3C platform. The granule begins at 02:15:00 hours. The resolution is 1 Km.
FY3C_VIRRN_GBAL_L2_SST_MLT_GLL_ _POAD_5000M_MS.HDF
CMA nighttime daily L2 skin SST data for 03 May 2014, from VIRR multiple stations data collected from the FY-3C platform. The resolution is 5 Km.
L3_SST:
FY3C_VIRRD_GBAL_L3_SST_MLT_GLL_ _AOAM_5000M_MS.HDF
CMA daytime monthly L3 skin SST data for April 2014, from VIRR multiple stations data collected from the FY-3C platform. The resolution is 5 kilometer.

8. CMA SST data products specification crosscheck with GDS2.0
CMA
GDS2.0
Processing Level
L2 (granule)
L2P
L2 (daily fixed grid)
L3U
L3C L3
None
L3S L4
SST Type
 SSTskinSSTsubskin
SSTintSSTskinSSTsubskinSSTdepthSSTfndSSTblend
File Type
HDF5
netCDF or XML

9. Recommendations to IOC on GDS2.0
Add new code to table 7-10 GHRSST Unique SST Data Set Strings and Numeric Codes..
Recommendations to IOC on GDS2.0
Add new code to table 7-2 Regional Data Assembly Centre (RDAC) code table.
RDAC Code
GHRSST RDAC Name
CMA
China Meteorological Administration
Add new code to table 7-5 L2P <Product String> Table, with platform and sensor.
L2P <Product String>
Satellite Platform
Satellite
Sensor
Description
VIRR
FY3<X>
Visible and Infrared Radiometer (VIRR) on FY3<X>, where X is one of A,B,or C

10. Recommendations to IOC on GDS2.0
Add new code to table 7-10 GHRSST Unique SST Data Set Strings and Numeric Codes..
L3 <Product String>
RDAC
Description
VIRR_FY3<X>
CMA
L3 VIRR SST products from VIRR on FY3<X>, where X is one of A,B,or C
Add new code to table 7-10 GHRSST Unique SST Data Set Strings and Numeric Codes.
Unique Data Set String
Product Version
Numeric Code
Description
VIRR_FY3C_CMA_L2P_V1.0 1 72
FY3C VIRR SST Version 1.0 L2P from CMA
VIRR_FY3C_CMA_L3C_V1.0 73
FY3C VIRR SST Version 1.0 L3C from CMA

11. Thanks for your attention
The End
Thanks for your attention

12. Compare FY3C VIRR 5minutes granule SST against Daily OISST算法
样本类型 偏差
绝对偏差
均方根
总样本数
百分比 白天
最优样本
-0.35
0.74
0.93
71%
全样本
-0.59
1.08
1.43 夜间
-0.30
0.75
0.95
67%
-0.76
1.22
1.64
白天精度： -0.35±0.93°C
夜间精度： -0.30±0.95°C
反演精度满足小于1.2°C的设计指标 12