Understanding past climates requires data extending beyond modern instrumental records. This study shows that blue intensity (BI) measurements from European larch trees in the Southern Rhaetian Alps provide a stronger proxy for reconstructing past summer temperatures than traditional tree-ring-width data. BI processing enables regional-scale reconstructions and helps extend these reconstructions to the Mediterranean Basin and northern Europe, with excellent correlations to existing data.

During the Last Deglaciation, global surface temperature rose by about 4–7 °C over several millennia. We show that changes in year-to-year up to century-to-century fluctuations of temperature and precipitation during the Deglaciation were mostly larger than during either the preceding or succeeding more stable periods in 15 climate model simulations. The analysis demonstrates how ice sheets, meltwater, and volcanism influence simulated variability to inform future simulation protocols.

We analyse a southern Siberian stalagmite to reconstruct soil respiration, wildfire, and vegetation trends during the Last Interglacial (LIG) (124.1–118.8 ka) and the Holocene (10–0 ka). Wildfires were more prevalent during the LIG than the Holocene and were supported by fire-prone species, low soil respiration, and a greater difference between summer and winter temperature. We show that vegetation type and summer/winter temperature contrast are strong drivers of Siberian wildfires.

Changes in upwelling intensity of the Benguela upwelling region during the last glacial motivated us to investigate the local CO₂ history during the last glacial-to-interglacial transition. Using various geochemical tracers on archives from both subsurface and surface waters reveals enhanced storage of carbon at depth during the Last Glacial Maximum. An efficient biological pump likely prevented outgassing of CO₂ from intermediate depth to the atmosphere.

This work explores the spatial distribution of halite and gypsum within salt giants that formed in semi-enclosed basins via numerical box models. The results are compared to the Messinian salt giant, while our description of restrictions makes them transferable to other basins. As such, we propose a general timeline for precipitation patterns. Our results indicate that it is unlikely for gypsum and halite to precipitate simultaneously without additional internal restriction.

A fully coupled atmosphere–ocean–ice-sheet–solid-earth model was applied to simulate the time from the Last Glacial Maximum (about 25 000 years before the present) to the pre-industrial period. The model simulations are compared to observational estimates. During this climate transition, the model simulates several abrupt changes in the North Atlantic region, which are initiated by different processes. The underlying mechanisms are analysed and described.