This Milankovic Medalist paper represents a tour de force, addressing a complex yet crucial question: the evolution of global climate over the past 4.5 million years. This paper makes a significant contribution to the geoscience community by providing a self-consistent decomposition of global mean benthic δ18O into its temperature and seawater (ice volume) components. This approach is consistent with independent estimates of global mean sea surface temperature (GMSST) and sea level constraints.The analysis incorporates numerous high-resolution records spanning this period and highlights two distinct climatic regimes: • Before 1.5 million years ago, a warm period characterized by smaller-amplitude ice sheet and sea level cycles, primarily driven by obliquity timescales. • Following the Mid-Pleistocene Transition (MPT), i.e. after 1 million years, a well-documented increase in the amplitude of glacial cycles became evident. The central finding of the study is that, during the MPT, there was a shift in ocean heat storage efficiency (HSE). Prior to this transition, HSE remained low and constant, whereas after the MPT, it doubled and stabilized at a higher value. This finding is supported by the observation of subtle differential changes in global mean SST and mean ocean temperature (MOT), which appear to be time-dependent. These observations suggest a potential fundamental shift in oceanic heat storage dynamics.

The paper presents a state-of-the-are Holocene reconstruction of North American vegetation shifts, including a discussion of drivers and potential feedbacks on climate.

These data are unique to Greenland, particularly from the base of the Camp Century ice core. These data, which show several periods of glaciation and non-glaciation in northwest Greenland prior to the formation of the current ice cap, should be of great interest to the paleo community, from paleoecologists to modelers.

The paper shows that historical records of wine yield and quality from Central Europe (1416–1988) can be combined into a Yield Quality Index (YQI). This index serves as a reliable indicator of climate conditions from May to July. Using long-term tax, tithe, and estate records from the Moselle region in Germany and the Swiss Plateau, the study shows that high YQI values correspond to warm summers, early harvests, and supportive tree-ring evidence. Conversely, low values often reflect cold summers or frost damage. These results confirm that wine production data can significantly improve climate reconstructions and help explain the social and economic impacts of past climate extremes.

Stevenard et al. present the first compilation of SST records covering the period 350 to 300 ka, encompassing Termination IV and the subsequent interglacial (Marine isotope stage, MIS, 9e). They show that surface temperatures rose by ~5.7 °C during Termination IV, comparable to the estimated warming of Terminations I and II. Their results further suggest that globally averaged SST during MIS9e were similar to the pre-industrial. This reflects a highly spatially heterogeneous interglacial optimum, likely influenced by variations in the strength of the Atlantic Meridional Overturning Circulation.