Climate of the Past 

The paper entitled "Continuous synchronization of the Greenland ice-core and U-Th timescales using probabilistic inversion" presents a first and new continuously measured transfer function that quantifies the age difference between the GICC05 and the U-Th timescale during the last ice age. The transfer function was estimated using a new automated algorithm for proxy data alignment. The approach was the subject of much discussion with the various referees who evaluated it, but it is at least described clearly enough for the community to form its own opinion and henceforth use it.

This is a very interesting proxy development based on grape production. So far, grape harvest dates (ghd) are well-known proxies of past temperatures from April to July that can generate very accurate and fascinating time series (see Labbé et al. 2019, https://doi.org/10.5194/cp-15-1485-2019). However, the analysis of wine must has not yet been considered, although the present manuscript shows that it is a highly potential climate proxy when other related information is missing. This study opens the door to exciting future studies

This article presents an interesting link between climate and weather patterns, and in particular how this may have impacted recent human history.

This paper presents the first gridded reconstruction of the summer (June, July, and August) vapor pressure deficit (VPD) for the past four centuries at the European level. The reconstruction shows that from the mid-1700s, a trend towards higher summer VPD occurred in Central Europe and the Mediterranean region, a trend that has continued through the observational period. The reconstruction is based on 26 European tree-ring oxygen isotope records .

The paper submitted by Meister and colleagues presents the first comprehensive compilation and assessment of diatom oxygen isotope records in lake sediments (δ18OBSi). The authors have supplemented these data with additional lake basin parameters (such as catchment size and residence times). The manuscript first infers the spatial and temporal coverage of δ18OBSi records and then discusses common hemispheric trends on centennial and millennial time scales, with key results such as: - Common patterns for hydrologically open lakes in extra-tropical regions of the Northern Hemisphere. - Common trends during the Common Era and throughout the Holocene corresponding to known climatic epochs such as the Holocene Thermal Maximum, Neoglacial cooling, the Medieval Climate Anomaly and the Little Ice Age. This is a well-written manuscript that should make a valuable contribution to reconstructions of past climates.