The 17th BMB-NCAR Project Meeting

Time: 02:00~03:45 pm, Jan 31, 2006

Participants: Dr. Huang, Dr. Guo, and Jiqin Zhong

1. Discuss the project progress

Jiqin took the WRF tutorial last week. The tutorial gave her a good overview of the WRF modeling system including SI, real, WRF model and WRF-Var.

With the help from Dr. Guo, Jiqin did experiments with sfc_assi option 2 successfully. Single AWS observation tests were made with sfc_assi option set to 1 and 2 respectively. Results showed that the structures of the analysis increment are similar to each other, but the amplitude of the increment when sfc_assi option set to 2 is smaller than the one that when sfc_assi options set to 1. There are differences between the two surface schemes. Dr. Huang pointed out that with sfc_assi=2, the observation error should be reduced.

Jiqin also did single wind profiler observation test and single GPS PW observation test. The analysis increment looked basically normal.

An unrealistic relative humidity increment maximum was shown on RIP figures for all single observation experiment. Dr Guo suggested Jiqin try to plot increments directly from ANALYSIS_INCREMENT file with GRAPH package. Dr. Huang suggested Jiqin re-run experiments with a WRF 6h forecast as background to eliminate the noise brought by background field.

2. Make a task list

l Get the verification package from Dr. Guo.

l Provide the local observation site location figure.

l Try to understand the relative humidity problem on upper levels.

l Modify the observation error file to reduce the AWS observation error and use single AWS observation test to check how analysis increment reacts.

l Continue the serial experiments: run EXP11 with the sfc_assi=2 and then using a reduced sigma_o.

l Continue the work on the assimilation of GPS ZTD in WRF-Var. Collect a new GPS data set (should be ~ 10 stations) and prepare data assimilation runs with PW and ZTD data.

 3. Next meeting

 The next meeting will be at 2:00 pm, Feb 14, 2006.