I found this 2012 listening report on the Quebec amateur club website. It involves CW transmission by the Brazilian Navy at the same frequency of 16976 kHz.

https://craq.club/files/documents/Archives/numeriques.pdf

Is it just a coincidence that our mysterious CW station was reported by Brazil’s SWL?

We have obtained the following content: Google translation on radio transmitted French reports and Portuguese language books and correction of some hypothetical errors:

This is a small piece of weather report sent by PWZ (Brazilian Navy) in packer I.

……AREA VENT.

WAVES 5/6 with Burst 7. WAVES of

W/sw 1.5/2.5 pass5/2.5 no

REST NW/SW 4/5 WITH BLAST HANGING AROUND

Se/ne 3/4 southwest RESA. PASSAND5 WAVES IN THE SOUTHWEST OF THE AREA.

NORTHERN OCEAN AREA

WIND SE/E South of ECUADOR and E/NE 3/4 before the area.

QRU/ZKM QRU/ZKM QRU/ZKM

Rio de Janeiro Navy message ended at packer I (16976 kHz on 04/30/2012)