Fig. 5: Onça speleothem record vs. reconstructed annual mean temperature.
From: Modern anthropogenic drought in Central Brazil unprecedented during last 700 years
a comparison between the ensemble mean annual surface temperature anomaly for 12°–16° S to 41°–47° W from PHYDA with Mg/Ca from Onça2 speleothem; b–d same as in the (a) but using δ13C and δ18O respectively, from the composite from Onça2 and Onça4 speleothems. High δ13C, δ18O, and Mg/Ca values indicate highly evaporative conditions, driven by reduced recharge, lower cave relative humidity and warmer temperatures.
