It is high res data from Greenland ice cores. Who made this specific high res graph I do not have a source for but the Greenland ice core data can be found here: https://www.nature.com/articles/s41467-021-22241-w/figures/1
Really wish I could get all of the warming spikes in high res on demand but I’ve never found it. Rate of change of earth’s warming has clearly been much more dramatic in the past and had nothing to do with atmospheric co2 or humanity in general.
Lmao look at earth’s average temps zoomed out:

