The top-level JMC Code L First Code Improvement directory contains atm, ocn and esmf_top subdirectories along with scripts and files required to build execute in batch ( runtest.sh) and validate (STDOUT.0000.ref) the improvement 1 ESMF based code. The file README.milestonef, also at the top-level, contains details of the contents of each of these directories, files and scripts as well as pointers to the MITgcm release1 documentation (http://mitgcm.org/sealion). For the runtest.sh script to execute correctly the dynamically linked library search paths /usr/local/pkg/lahey/lf9562/lib and /usr/local/pkg/ESMF/ESMF_1_0_4/mpich-1.2.5..10/lahey/lib/libO/Linux.lahey.32.default must be used.