The year from March
2007 to March 2008 is the third year of the BMB-UCAR WRF 3D-Var project. A detailed working plan for this year is
required. According to the existing SoW and the working progress for the second
year (March 2006 –
March 2007), there are 2 tasks in the
last year: Task 5 and Task 6.
WeÕve already had the
background error statistics for 9-km domain. However, the background
error statistics for 3-km domain is also required for the purpose of 27/9/3 km
operational run of the WRF 3DVAR system. BMB staff will calculate 3-km resolution
BES and further tune it and the observation errors with the BE objective tuning
code developed by NCAR/MMM staff. In addition, to keep the
NCAR/MMM staff will provide the technical consultation on these tasks.
Period: Year 3,
Month 1-6
Resources required: BMB 9 man-months, NCAR: 1.5 man-month
BMB staff will perform calculation of background error
statistics necessary for the operational use of the WRF 3DVAR system under the
general guidance of NCAR/MMM staff,
especially for the nested 3-km domain.
Period: Year 1,
Month 1-2
Resources required: BMB: Fan 2.0, NCAR: Guo 0.5
Deliverables:
1. A report on the tuning of high-resolution (3km) background error statistics of WRF data assimilation system (NCAR & BMB).
BMB staff will update the current version of digital filter initialization (DFI) codes to the latest released WRF version (v2.2). NCAR/MMM staff will provide technical and theoretical advices, and review the code.
Period: Year 1,
Month 1-2
Resources required: BMB: Chen 2.0; NCAR: Huang 0.25;
Deliverables:
1. A
working version of DFI can be implemented on WRFV2.2.
BMB staff has constructed a WRF-based cycling system on 9-km domain with the ability to assimilate all of the datasets available to BMB. However, both of the horizontal and time resolutions are required to be improved to 3km and 3-hour according to the SoW. BMB staff will perform cycling experiments with the required configuration and the updated 3-km BES. In addition, the FGAT technique in cycling run can be tried to account for BMB AWS and GPS/PW data. If possible, a code to calculate the DFS (Degrees of Freedom for Signal) for special observations can be developed. NCAR/MMM will provide technical assistance in necessary.
Period: Year 3,
Month 1-6
Resources required: BMB: Chen 1, Fan 4;
NCAR: Guo 0.5,
Huang 0.25
Deliverables:
1. A
WRF 3DVAR cycling system to be
able to assimilate data sets available to BMB and run in a hot-start
style on 3-km
domain with 3-hour
interval (BMB & NCAR).
BMB staff will monitor the performance of the WRF 3DVAR system in a six-month (March to September) pre-operational testing. BMB staff will identify problems of WRF 3DVAR system. NCAR/MMM staff will work with BMB staff on resolving issues identified during the pre-operational testing.
Period: Year 3,
Month 1-12
Resources required: BMB: 11 man-month;
NCAR: 3 man-month
BMB staff will perform observation system experiments (OSE) to assess the quality and relative significance of different kinds of observations including GPS PW, AWS, intensive radiosondes and GTS data under the guidance of NCAR staff. BMB staff will prepare a report on the preliminary results and analysis of OSE.
Period: Year 3, Month 4-8
Resources required: BMB: Zhong 3.0, NCAR: Huang 0.25
Deliverables:
1. A report on the preliminary results and analysis of OSE.
BMB staff will compare the verification scores of pre-operational WRF (cycling) system with the operational MM5 system each month. NCAR/MMM staff will work with BMB staff to provide a report.
Period: Year 3,
Month 1-12
Resources required: BMB: Zhong 2.0, NCAR:
Huang 0.25; Guo 0.3;
Deliverables:
1. A report on the comparison of performances between the two systems (BMB & NCAR).
An implementation
of WRF DFI method will be performed on the cycling system with 3-hr interval
and 3km resolution to suppress the noise and identify the originations of the
noises in WRF cycling system. NCAR/MMM will provide some necessary
technical assistance.
Period: Year 3,
Month 3-12
Resources required: BMB: Chen 4, Fan 2; NCAR: Huang 0.2
Deliverables:
1. A report of DFI method implemented on BMB cycling system with 3hr interval (BMB & NCAR).
BMB staff will analyze the performance statistics of the WRF system in the BMB operational environment under the general guidance of NCAR/MMM staff. Based on the diagnostics of the results, NCAR staff will provide recommendation for updating and tuning of the WRF system. NCAR staff will collaborate with BMB staff on cases studies that leads to improvement to BMBÕs forecast system.
Period: Year 3, Month 1-6
Resources required: BMB: 6 man-month (Zheng), NCAR: Wang 1.5
Deliverables:
1. A report on the case studies of BMB operational WRF model (BMB & NCAR).
A verification package developed by NCAR staff has been implemented on BMB WRF pre-operational system. However, some functions (verification of surface variables) in the package need to be further enhanced to meet the demands of operational performance evaluation. NCAR staff will develop an algorithm for verification of 2-m temperature and 10-m wind directly output from the output instead of the temperature and wind on the lowest level of the model. BMB staff will perform the test and the final implementation.
Period: Year 3,
Month 7-8
Resources required: BMB: Zhong 1; NCAR Guo 0. 5
Deliverables:
1. A new verification package that can perform verification of 2-m temperature and 10-m wind instead of the temperature and wind on the lowest level of the model.