Impact of modern software engineering practices on the capabilities of an atmospheric general circulation model

In this note, we discuss the relevance and impact of a software engineering effort at NAL on the forecast model in operation at the National Centre for Medium Range Weather Forecasting (NCMRWF). The code has been re-written exploiting the features of Fortran 90. As a direct consequence of appropriate reengineering efforts on the code, it is both easy to comprehend and modify. The reengineered code is appreciably shorter (number of lines in the code reduced by 55%) and can run on a variety of computing platforms including a PC, without the need for any further modifications to the code