NOTE: The OST album for the Studio Ghibli film "Ocean Waves" ("海がきこえる" or "Umiga Kikoeru") contains TWO related tracks. Track 02, "Umiga Kikoeru," is instrumental in the key of G-Bb-G (approx. 6 min.). Track 10, "Umini Naretara" (ending theme), is vocal in the key of D (approx. 4.5 min.). Both of these pieces are composed by Shigeru Nagata and develop around the same theme in different ways.
This is a set of two versions of scores as shown below:
[A] Corresponding to the full length of the OST Track 10 (about 6 min.)
[B] Shorter and simpler (only the first movement)
[C] Half of Version A (first & fourth movements) [ADDED: 2023-04-30]
These arrangements are based on a transcription of the OST and as such, other instruments (guitar, cello, strings/violins) are also represented where applicable.
Note: The linked video includes both versions A and B in that order.