HadISST data: https://www.metoffice.gov.uk/hadobs/hadisst/terms_and_conditions.html

The image 50-natural-earth-1-downsampled.png is downsampled from Natural Earth data whose conditions are stated at https://www.naturalearthdata.com/about/terms-of-use/ (public domain).

gshhs is LGPL, but their documentation doesn't state a version https://www.soest.hawaii.edu/pwessel/gshhg/.
The same data sets are part of the GMT package which is packaged in linux distributions, including debian.

The image Miriam.A2012270.2050.2km.jpg is from the Rapid Response section of the NASA LANCE data, which states it is in the public domain https://earthdata.nasa.gov/faq#ed-rapid-response-faq
