Solar, Atmospheric, and Volcanic Impacts on 10 Be Depositions in Greenland and Antarctica During the Last 100 Years

Cosmogenic radionuclides (e.g., 10 Be) from ice cores are a powerful tool for solar reconstructions back in time. However, superimposed on the solar signal, other factors like weather/climate and volcanic influences on 10 Be can complicate the interpretation of 10 Be data. A comprehensive study of 10 Be records over the recent period, when atmospheric 10 Be production and meteorological conditions are relatively well‐known, can improve our interpretation of 10 Be records. Here we conduct a systematic study of the production and climate/volcanic signals in Antarctica and Greenland 10 Be records, including a new 10 Be record from the E ast GR eenland I ce‐core P roject site. Greenland and Antarctica records show significant decreasing trends (5%–6.5%/decade) for 1900–1950, which is comparable with the expected production rate inferred from sunspot observations. By comparing 10 Be records with reanalysis data and atmospheric circulation patterns, 10 Be records from Southern/Southeastern Greenland are significantly correlated with the Scandinavia pattern. Stacking 10 Be records from different locations can enhance the production signal. However, this approach is not always straightforward as uncertainties in some records can lead to a weaker solar signal. A strategy can be employed to select records for the bipolar stack by comparing Greenland records with Antarctica records, assuming the shared signal is a production signal. Finally, we observe significant increases (36%–64%) in 10 Be depositions in Greenland related to the Agung eruption. This large increase in Greenland 10 Be records after the Agung eruption, could be partly explained by the enhanced air mass transport from mid‐latitudes coinciding with the decreased precipitation en‐route. Cosmogenic radionuclides (e.g., 10 Be) from ice cores are useful proxies for reconstructing the solar variability in the past. However, besides the solar signal, there are also atmospheric and volcanic signals in 10 Be records measured from ice cores. It is important to understand those signals before we can reliably apply 10 Be records for solar reconstructions. A study of 10 Be records over the recent period, when atmospheric 10 Be production and meteorological conditions are relatively well‐known, can improve our interpretation of polar 10 Be records. In this study, we conduct a systematic study of the production and climate/volcanic signals in 14 10 Be records, including a new 10 Be record from E ast GR eenland I ce‐