1.1 What is the SPA?

The SPA is a collection of FORTRAN90 modules, subroutines, and functions that create a working environment for standard meteorological calculations. The include data access routines (generally subroutines), setup and formatting routines (again, mostly subroutines), and calculation subprograms (generally generic functions). It is this latter set of routines that will be of primary interest to the user or developer who wishes to access or extend the SPA without introducing a new data format capability (which is, of course, much appreciated).

These subprograms are intended to abstract the user (and even the end-product developer) from the particulars of the data format supplied, and to make interfacing with existing routines as painless as possible. Inevitably, there will be small bugs in some of the calculations which will be caught and corrected over time — the end result will be a package which is as error-free as possible and meets the needs of users in the meteorological community.