last changed June 8, 2004 OBSERVATION SYSTEM SIMULATION EXPERIMENT OSSE is an MITgcm configuration to simulate data assimilation with a deterministic ensemble Kalman filter and a model of a rotating tank of water with an ice bucket at the center. INSTALLATION At the time of this writing, the OSSE requires MITgcm checkpoint48 to compile and run. MITgcm can be obtained from . If downloading from the CVS server, use the command cvs co -r 'checkpoint48' MITgcm in order to specify the correct version. Read the instructions on the the webpage before trying to use the CVS server. The OSSE directory tree can be obtained from the MITgcm CVS repository with the command cvs co MITgcm_contrib/osse The code and its revision history can be browsed at A good place to put the osse directory tree is in MITgcm/verification, where examples and test examples of MITgcm configurations are kept. CONTENTS code: modifications to MITgcm to run in cyclindrical coordinates. At the time of this writing, it requires checkpoint48 to compile and run. input: initialization and input files for MITgcm filter: source and data files to run the data assimilation and Kalman filter. utils: assorted Matlab m-files EnKF: empty run: empty COMPILING AND RUNNING THE MODEL The following series of commands creates the MITgcm executable. From the MITgcm root: cd verification/osse mkdir build # directory name is arbitrary cd build ../../../tools/genmake -mods=../code # creates makefile make depend # contructs Fortran code from model codebase make # makes executable mitgcmuv Try a test run, while redirecting the standard output to a file. The input directory contains files that should be present in the working directory when you run mitgcmuv. It is recommended that you copy the input contents to a different directory for running -- mitgcmuv does not change them, but they can be lost in the multitudes of output files. The data assimilation code is made by typing ``make'' in the filter directory.