Extended Data Fig. 5: Latest Paleocene/ earliest Eocene (LPEE) siderite continental temperatures in comparison to the present-day.

Reconstructions are compared to present-day temperatures at the respective sites or the longitudinal range of present-day temperatures considering the 2σ uncertainty in clumped isotope-based temperatures. We compared the Colombian, southern Alaskan and Siberian reconstructions to the entire present-day longitudinal range of temperatures (circles and dashes lines). Other reconstructions are compared to the respective temperature at the site in the present-day (stars), with the exception of the sites in Wyoming and Colorado that are currently located at high altitude. Black represents comparisons to present-day mean annual temperature and red represents comparisons to present-day temperature of the warmest months, considering the summer-bias in high latitude temperatures.