Equivalent graph for southern hemiphere SST:
https://climategrog.wordpress.com/?attachment_id=312
For explanation of derivation see description accompanying a similar graph of HadCRUT4 data:
https://climategrog.wordpress.com/?attachment_id=285
The volcano stack of hadSST3 without integration of degree.days is here:
https://climategrog.wordpress.com/?attachment_id=278