The manuscript by Herzschuh et al. presents a novel approach for deriving quantitative summer temperature estimates from Lake sediments. This method has the potential to substantially improve terrestrial temperature reconstructions and thereby advance our understanding of past continental climate change.

This manuscript introduces an innovative method for identifying cryptotephra in Antarctic ice cores, which could lead to significant new findings at Mount Brown South (MBS) and throughout Antarctica. The manuscript describes the identification of two new cryptotephra horizons in the MBS ice core from Wilhelm II Land in Antarctica. These cryptotephra originate from the mid-1980s eruptive period of Mt. Erebus and the cataclysmic 1991 eruption of Cerro Hudson. These two tephra horizons are an important addition to the East Antarctic tephrochronological framework. The findings of this study challenge previous assumptions about transport trajectories and pathways and satellite-era ice core chronologies, offering new insights into atmospheric circulation dynamics.

The goal of the paper presented by M. Meijers et al. is to present a new, large data set of stable carbon isotope analyses performed on carbonates from late Miocene to Holocene sites in Anatolia. By combining their analyses with previously published carbonate d13C data, as well as published paleoclimate estimates from the region, the authors demonstrate secular changes and restructuring of paleofloral communities since ~10 Ma. Despite being a hotspot of projected anthropogenic climatic change, the evolutionary and climatic processes that shaped terrestrial ecosystems in the northeastern Mediterranean over the last 10 million years remain largely elusive. Whereas the expansion of C4 grasslands is well documented in regions such as eastern Africa and southern Asia, the dynamics in western Eurasia remain poorly understood. This gap in knowledge is critical for our understanding of how terrestrial ecosystems respond to large climatic shifts over geological timescales. In this manuscript, we present the first comprehensive stable carbon isotope record of pedogenic carbonates from Anatolia (Türkiye), spanning the last ten million years. Our results reveal that C4 grasslands in this region emerged during Late Miocene Global Cooling, simultaneously with southern Asian localities. Our study offers a unique perspective on a striking and largely unexpected feature: the permanent return to C3-dominated vegetation during the Early Pliocene – a phenomenon not observed elsewhere. We propose that this reversal to C3 vegetation was driven by regional hydroclimatic changes, in particular by a transition in rainfall seasonality, from a summer-dominated precipitation regime to a Mediterranean-style winter precipitation regime.

This study provides valuable insight into the timing of meltwater events and associated response of AMOC during the last deglaciation. The strength of the work lies in its precisely dated chronology from a northwest Iberian stalagmite, which overcomes the chronological limitations of North Atlantic sediment records. As highlighted by Reviewer 2 “this represents a substantial advance given the impasse in what is possible based on the less precise dates of sediment cores in this interval.” The analysis of multiple proxies within the same stalagmite allows the authors to directly compare the timing of surface ocean freshening relative to regional temperature changes. Their findings reinforce the hypothesis that the AMOC response to freshwater forcing is nonlinear and may involve threshold-like transitions that are dependent on background climate states. This has broader relevance to the ongoing debate surrounding future AMOC stability.

The expansion of the glacial ice shield on Iceland and its lateral expansion is a big unknown in paleoclimate and paleoceanography. Its expansion into the Denmark Strait region has major implication on the water mass exchange across the Strait, in particular for the outlfow of Denmark Strait Overflow Water. This modeling study is bringing exciting new insights and constrains on the behavior of the Iceland ice cap throughout the last glacial cycle.