| 17 Jul 2025
Climate-related signals in the GV7-C ice core from East Antarctica for 1782–2013 CE: Potential relevance to climate and teleconnections between tropics and Antarctica
Abstract. This study investigates climate-related signals preserved in the GV7-C ice core from East Antarctica (1782–2013 CE), analyzing stable water isotopes (δ¹⁸O and d-excess) and snow accumulation (SA). Annual data were compared with climate indices representing the El Niño–Southern Oscillation (Niño3.4, SOI), Southern Annular Mode (SAM), Indian Ocean Dipole (IOD), and sea surface temperature (SST) anomalies in the southeastern Indian Ocean (SST-SEIO). During 1957–2013 CE, δ¹⁸O correlated intermittently with Pacific Ocean sector indices, while d-excess consistently correlated with SAM, IOD, and SST-SEIO, indicating stable moisture sources from the Indian Ocean. Over the longer period (1872–2013 CE), δ¹⁸O correlations weakened, suggesting shifting climatic influences, whereas d-excess retained correlations, emphasizing its reliability for tracking moisture-source variability. Snow accumulation showed weak and inconsistent correlations with climatic variables, suggesting multiple influencing factors. Spatial correlation analyses revealed that δ¹⁸O and d-excess signals primarily reflect conditions in the Pacific and Indian Ocean sectors, respectively. These findings highlight dynamic teleconnections between Antarctic climate and tropical ocean conditions, underscoring the complexity of interpreting Antarctic ice core records in climate variability studies and emphasizing the importance of considering varying temporal resolutions and climatic contexts.
The manuscript by Nyamgerel et al investigates climate related signals in the GV7-C ice core located in East Antarctica, and the potential teleconnections between the tropics and Antarctica. While the manuscript addresses an important question regarding the climate variability signals within the GV7-C ice core in East Antarctica, major revisions are necessary before it can be considered for publication.
My main concerns that need to be addressed before further review are:
(1) Additional detail added to the method. Currently the method lacks sufficient detail to understand and have confidence in the results and interpretation. My key concerns include:
(2) Most of the figures are in the supplementary material. These are referred to in the results and essential to be able to understand the results and interpretation discussed so need to be made more concise to be able to be included in the main text.
(3) Manuscript needs a major restructure. Currently there are a lot of discussion points in the results and it is challenging to determine what the key findings of the manuscript are. These need to be obvious based on the figures and results section, which is currently not the case with multiple figures in the supplementary and no clear structure to the result and discussion section.
(4) Missing key relevant references. One example is around the studies that investigate the link between weather regimes (including atmospheric rivers) and their links to modes of climate variability in the region, and how these influence the interpretation of climate signals in ice cores. Some relevant examples are:
Given the above, I recommend major revisions to strengthen the methodological transparency, clarify results and make the figures more concise and related to the key messages of the paper, and restructure to improve the interpretation and integration of findings within the broader Antarctic climate variability research.