We compare state of polarization (SoP) measurements on a subsea telecommunication cable with reference ocean wave variability data to quantitatively assess the performance of SoP as a sensor of opportunity. We find correlations of up to 70% and observe both wind and swell waves simultaneously perturbing two distinct cable regions. While SoP data is generally non-trivial to interpret, the technique is practical to implement, remotely-operated and compatible with existing cable networks