1. Implementation of RRR in China
(Evaluate the impact of surface observations from China Automatic Surface Observation Network on numerical weather forecast)
Jianxia Guo
Meteorological Observation Center of CMA

2. Outline
Background
Implementation of the WMO RRR (The Rolling Review of Requirements) Process in china
The on going work and the vision

3. Background Large of area Complex of topography
Diverse of weather systems
Frequent of meteorological disasters
Big challenge for meteorological observation and weather forecast
(73°33′E~135°05′E,3°51′N~53°33′N)

4. National surface observation stations Doppler Weather Radars
Background
The Current surface-based Network
National surface observation stations
2423
Surface Observation
AWS
Marine met. Station 475
Agro-met. Observation 2075
Environmental Met. Obs.
Upper Air Observation
Weather Radar Network 181
Wind profile 69
GNSS/met
Raidosond
120+3
Doppler Weather Radars
181

5. Issues How to make a integrated network in such a complex situation?
Establish a integrated view to the various observation networks.
Have effective tools to handle the complex situation and various temporal and spatial scales observation.
Develop and design the new observation or improve the existing observation based on the integrated view.

6. Outline
Background
Implementation of the WMO RRR (The Rolling Requirements Review) Process in China
The on going work and the vision

7. EVALUATION OF REQUIREMENTS AGAINST SYSTEM CAPABILITIES

8. User requirements to Observation
Application areas
Global numerical weather prediction;
Regional numerical weather prediction;
Synoptic meteorology;
Nowcasting and very short-range forecasting;
Seasonal and inter-annual forecasts;
Atmospheric chemistry;
Aeronautical meteorology;
Climate variability;
Climate change;
Marine meteorology;
Hydrology;
Agricultural meteorology.
Requirements statement
(quantitative)
Horizontal and vertical
resolution;
frequency
(observation cycle);
Timeliness
(delay in availability) ;
Accuracy
(acceptable root mean
square error and any
limitations on bias).
Maximum requirement
Threshold requirement

9. Observing system capabilities analysis and review

10. The critical review
Numerical model and Data assimilation are important and useful tool for critical review ;
Make the critical review process objective;
Establish a integrated view to the observing systems;
Quantify the contribution of each observing systems to NWP;
Target the observation area for special weather system;
Assess the quality of the each observation;
Produce new observation products;
Design the observation network.

11. Practices Optimization of the reference climate observation network;
Team work, from 2009 to 2012.
Optimization of the surface AWS network.
Team work, on going since 2014.

12. Optimization of the reference climate observation network
The requirements:
Representativeness (away from the local influence).
Sustainable (lasting for a long time without interference).
Accuracy (meet the GCOS requirements)
The coverage (the network should cover the whole country).

13. Cont’ The capabilities data base
The surrounding environment detail from the field investments.
The series of historical
land-use type around
the site of 50km from
MODIS.

14. Cont’ The satellite images over the
site to calculate the proportion of the city area around the site.

15. Cont’
The layout of city developing plan of 20 or 30 years from the local government near the site.
The observation data records.
The information of the location, instruments, calibration etc.

16. Cont’ The critical review Single station assessment
The grades of the surrounding environs.
The quality of the data series.
The contribution of the representative area.
The impregnability by the city developing plan.

17. Cont’ The network assessment The coverage cost.
The covariance between the chosen network with the background.
Original
netwrok
Ratio of coverage
optimized
Station number
Temperature covariance

18. Cont’
The results
Degraded some stations from the climate reference station’s rank to the basic station’s rank;
Upgraded some good stations from the basic or ordinary station’s rank;
Established some new stations at the west part of china.

19. Optimization of the surface AWS network
National surface observation stations:2423
supported and managed by CMA
Unified criteria and standards
Regional automatic weather stations: 55680
supported by : CMA
local government
other organizations
managed by: local Meteorological
standards are not unified
most of them lack of calibration
Needs: NWP need more dense data than the national stations to evaluate the forecast results;
Meso-scale severe weather need to be captured by sufficient and credible data.

20. RRR process 2016 2015 2014 Comprehensive analysis and decision-making
decision-making and statement
Requirements and critical review 2
Requirements and critical review 1
Capability
Comprehensive analysis and decision-making
Requirements by NWP
(impact study)
The status of the existing AWS
Requirements by
severe weather capture
2016
2015
2014

21. Stage 1 (2014) Capabilities data base Collected metadata of AWS
Instruments
factory , type approval, deployed time, calibration
Running condition
power supply,  communication mode, access
Site
Location, area, land cover, surrounding environs, thunder prevention
Measurement elements
Provincial and local meteorological services all over the country participated in. Greatly contribute to the judgment of data credible.

22. Stage 2 (2015) Requirements analysis 1 Weather systems analysis
Focus on 7 types of weather systems that may induce the severe weather.(low pressure ,convergence line, low vortex, low trough, front, shear line, the subtropical high)
Scale, activity area
High-impact /severe weather analysis
Focus on 4 kinds of high-impact /severe weather (heavy rain, wind, hail and thunderstorm)
Occurrence source, developing and weakening area, moving route and other sensitive areas.
Forecasters from 31 province did the analysis.
They selected AWS in the important areas
according to the metadata.

23. Stage 3 (2016) NWP requirements analysis ( critical review)
Impact study
OSEs, OSSEs, FSO
Case study, period operational running test
Density variation test for the economic selections.
As the complex condition, different region may have different impact results.
National and 8 regional NWP centers have joined in this work.

24. cont’
A technical experts team has been established. Exchange the progress and problems frequently.
The technical detail has been determined
by the participants.
SMS completed 4 case studies and got some encouraged results. Dr. Sun Min will show the presentation soon.
INSTITUTE/CMA
NMC
MOC
north of China
east of China
south of China
centre of China
northeast of China
southwest of China
Xinjiang China
Northwest of China 
SCOPE
Nationwide
Beijing/Tianjin/Hebei/Shanxi/Neimenggu
Jiangsu/Zhejiang/Anhui/Fujian/Jiangxi/Shandong/ Shanghai
Guangdong /Guangxi/Hainan
Hubei/Henan/Hunan
Liaoning/Jilin/Heilongjiang …
Sichuan/Yunnan/Guizhou/Tibet/Chongqing
Xinjiang
Gansu/Shaanxi/Qinghai/Ningxia QC
GRAPES
MDOS
OPERATION
MODEL
WRF
WHMM
SWC-WARMS
ASSIMILATION
3DVar
4DVar
ADAS
SENSITIVITY TEST
osse+
ose
density
density+
batch 
batch

25. Preliminary case study
Case:, ,12UTC ,00UTC
Torrential rain caused by Low vortex shear
observation
24h precipitation
,00UTC ,00UTC

26. Model Model：WRF_V3.6.1 Assimilation ：WRFDA_V3.6.1, 3DVAR
Background: GSF Analysis 0.5〬*0.5〬
Period： ,12UTC~ 日,00UTC
Centre of D01：（29〬N, 110〬E）
Grid：171*171；253*241
Vertical ：41
Resolution：27km，9km
Steps：180s
Physics ：WRF double moment,6-class scheme
New Grell scheme

27. experiments Experiments name Data of assimilation
GTS synop + radiosonde 1
TRUE
with Regional AWS 2
EXP_NON_ASON
without Regional AWS 3
EXP_NON_ASON_T
Regional AWS without T 4
EXP_NON_ASON_P
Regional AWS without P 5
EXP_NON_ASON_TD
Regional AWS without TD 6
EXP_NON_ASON_V
Regional AWS without UV

28. ,12UTC
SNOP（6164，blue）
Radio sound（401，red）
,12UTC
Regional AWS（40308）

29. observation
TRUE

30. EXP_NON_ASON
EXP_NON_ASON_T
EXP_NON_ASON_TD
EXP_NON_ASON_P
EXP_NON_ASON_V
T>P>V>TD

32. Thanks for your attention! Any suggestions?