Find an example of repeated 1D measurements to replace the made up line example

[flekschas]

Measurements of the average temperature might be a neat example. This could (a) be interesting and (b) could come in handy for demonstrating how to create an interactive joyplot.

Something similar to http://www.realclimate.org/index.php/archives/2017/07/joy-plots-for-climate-change/