Figure 2. Sample time series analyses.

Time series illustrating commonly used palaeoenvironmental proxies. Vertical grey band represents position of mPWP. (a) Equatorial Atlantic SST based on alkenone unsaturation index⁴⁴. (b) Caribbean Sea oxygen isotope record¹¹¹ showing increasing salinity due to shoaling of the Central American Seaway. (c) Terrestrial record of the mean warmest month temperature from Lake El'gygytgyn⁵⁶. (d) Equatorial Pacific SST records based on Mg/Ca palaeothermometry⁵¹. (e) Estimates of Pliocene atmospheric CO₂ with pre-industrial and present day levels (horizontal dashed lines) for comparison; dark blue dots, δ¹³C (ref. ³); green band, δ¹¹B (ref. ⁷); pink band, alkenone⁵; red band, alkenone⁶; orange band, stomata⁴; yellow band, δ¹¹B (ref. ⁵); blue band, Ba/Ca⁵⁹; Modified from ref. 50.