Here is an interesting story on a measure of the changing climate you may not have thought of. Scientists at the University of British Columbia looked at menus from local restaurants over the last 130 years to see how the types of local seafood changed over time. By looking at the species of fish listed they were able to determine water temperatures and measure how they changed over time by watching how the local catches on the menus changed. You can read all about their sources of data and how they got to the temperatures in Atlas Obscura here.

An example of the menus that researchers drew on. This one is a Hotel Vancouver menu from June 1888. COURTESY OF CITY OF VANCOUVER ARCHIVES, AM1519-: PAM 1888-17