Both the DTC community GSI analysis system V3 and the WRFV3.3 have
been pre-compiled on the COMET classroom machines for the tutorial exercises.
Before starting the exercises, read the section on Setting up the GSI
system and follow the instruction found there. Since building the
community GSI system from scratch takes a significant amount of time, we
strongly recommended that users use the pre-compiled binaries to make the
best use of their laboratory time.
If upon completion of the exercise you want to experiment with building
GSI, please check here for
instructions.
These tutorial exercises are designed to be run on the Linux workstations
provided in COMET classroom. The source code and data files needed for
these exercises are provided, and available on an external directory.
Using the COMET Classroom machines
Setting up the GSI system
Case data summary and download
Basic Practical Cases
0). BUFR/PrepBUFR tools [practice]
To run any of the following practical cases, start with the basic run
script run_gsi.ksh, found in the
comGSI_v3/run directory,
and make the following modifications
[prepare].
These changes are used by all the basic exercises, and are specific to
using the COMET classroom. If you are running these exercises
elsewhere, additional modifications will be necessary.
1). Single Observation Tests:
2). Test with conventional data (prepbufr):
3). Test with conventional and satellite radiance data:
4). Test with conventional and gpsro data:
5). Test with conventional data and radar radial wind:
Advanced Practical Session A: Repeat basic practice with new data
A0). BUFR/PrepBUFR tools [practice]
Please repeat the basic case 1 to 5 using the new data at 00Z June 05, 2011.
Users can get the data following the instruction at:
Case data summary and download
Note: the BUFR/PrepBUFR files were created on IBM machine, which are
Big Endian files. To use these files on Linux machine, files need to
be converted to Little Endian files.
A1). Single Observation Tests:
A2). Test with conventional data (prepbufr):
A3). Test with conventional and satellite radiance data:
A4). Test with conventional and gpsro data:
A5). Test with conventional data and radar radial wind:
Advanced Practical Session B: cycling
This exercise is to illustrate the basic structure and flow of a cycling data
assimilation system. We will use the data on June 5, 2011 to manually run
data assimilation cycles from 00z to 12z with 6 hour interval on June 5.
The June 5, 2011 data have been used for the Advanced Practical session A and
users should have downloaded the data after play with the Advanced Practical cases.
If not, please check
Case data summary and download.
The flow chart of this practical cycling data assimilation system can be found
at here.
B1). GSI and ARW Cycling exercise:
B2). GSI and NMM Cycling exercise:
Advanced Practical Session C: Single Observation Test with Hybrid GSI
After compiling GSI and running the GSI introductory exercises successfully, the interested user can run the GSI hybrid by executing the following exercises.
These exercises demonstrate the GSI regional hybrid with a series of single observation sensitivity experiments.
The data for this exercise can be found in the tar file
/wrfhelp/GSI/Hybrid.tar.gz. Copy the tar file
for the Hybrid exercise to your working directory, and extract the data
before continuing to the rest of the exercise.
C). Single Observation Test with Hybrid GSI
Building GSI from Scratch
Obtaining, configuring, and compiling
