There is universal consensus within the scientific community that our earth’s climate is changing and that human activities have been the dominant driver of change in the past century (and will continue to be the dominant driver in coming decades/centuries). Despite seasonal-scale and inter-annual fluctuations, temperatures are trending upwards – albeit that the magnitudes of the trends vary across the planet. Here, we present evidence that water-temperatures in Pelorus Sound have risen by approximately 0.5°C since the 1980s.