Reprint – The Lighthouses of British Columbia


In February 2012 I wrote an article on the seawater sample collecting from the BC lighthouses here My story discussed the duties and .trials a lightkeeper had while obtaining the samples. This story details the use of the information collected from a scientist’s point of view.


The Lighthouses of British Columbia

by Allan Roberts

Not only are British Columbia’s lighthouses picturesque, and important for navigational purposes, but they also collect oceanographic data! You can access sea surface temperature (SST) and surface salinity data at the following website:

This website also has photographs of the lighthouses. (See below.)

Figure 1. Race Rocks (48.180 N, 123.320 W). Photo credit: Fisheries and Oceans Canada. Photograph obtained from:

Figure 2. Amphitrite Point (48.550 N, 125.320 W). Photo credit: Fisheries and Oceans Canada. Photograph obtained from:

I’ve compiled and plotted some of the data from the Race Rocks and Amphitrite Point lighthouses. Race Rocks (Figure 1) is near Victoria, while Amphitrite Point (Figure 2), on the west coast of Vancouver Island, is closer to Bamfield. The data plotted in Figure 3 are monthly averages for October, covering the years 1936 to 2011. The plot shows an evident contrast in SST and surface salinity between the two sites.

Figure 3. October averages for surface salinity plotted versus October averages for sea surface temperature. The data are from two different lighthouses: Race Rocks (48.180 N, 123.320 W) and Amphitrite Point (48.550 N, 125.320 W). Race Rocks is near Victoria, while Amphitrite Point is on the west coast of Vancouver Island. Data are not plotted for 1940 and 2007, because of missing values. Graphics produced with R (R Core Team, 2012). Data source: Fisheries and Oceans Canada, (accessed Oct. 9, 2012).

A peculiarity of the lighthouse data is that they are not collected at the same time every day, as explained on the lighthouse data website: “Sampling occurs at or near the daytime high tide” (Fisheries and Oceans Canada, 2012).

If you want data for ocean bottom temperature and salinity (as opposed to surface temperature and salinity), such data are available through NEPTUNE Canada, and through the VENUS network (NEPTUNE Canada, 2012; VENUS, 2012).


Fisheries and Oceans Canada. 2012. Website. Accessed Oct., 9, 2012:

NEPTUNE Canada, 2012. Website:

R Core Team, 2012. R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria.

VENUS network, 2012. Website:

The Awfully Long Thermometer!

 In an earlier story I wrote about how the lighthouse keepers have been doing sea water samples since the early 1930s – some of the oldest observations on the BC coast!

Now, with satellites we can get different temperatures of the sea – Sea Surface Temperatures for one – similar to what the lightkeepers do, but globally.

Sea surface temperatures have a large influence on climate and weather. For example, every 3 to 7 years a wide swath of the Pacific Ocean along the equator warms by 2 to 3 degrees Celsius. This warming is a hallmark of the climate pattern El Niño, which changes rainfall patterns around the globe, causing heavy rainfall in the southern United States and severe drought in Australia, Indonesia, and southern Asia. On a smaller scale, ocean temperatures influence the development of tropical cyclones (hurricanes and typhoons), which draw energy from warm ocean waters to form and intensify. – NASA Earth Observatory Continue reading

Ocean Water Samples

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..

Kains Island (Quatsino) lighthouse

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