One of the duties of a lighthouse keeper on some stations, was to do a daily Sea Water sample. It was started very early on (see the story here), before the advent of Global warming, and the observed data has been beneficial in many ways as you will see at the bottom..

In the above-mentioned story from Kains Island lighthouse, the samples started in 1935, so we have seventy-seven (77) years of ocean data. Also in the story is the fact that in the early years . . .
. . . the small glass bottles of sea water with cork stoppers were stored in wooden boxes with many little squares, one for each bottle1. These boxes would be shipped out when the supply ship re-supplied the station once a year, usually in July. Continue reading Ocean Water Samples