“…Beryllium-7 ( 7 Be) is a cosmogenic radionuclide widely monitored and analyzed around the world (e.g., Tositti et al, 2004Tositti et al, , 2014Gourdin et al, 2014;Sýkora et al, 2017). Due to its relatively long radioactive half-life (53.22 d) and its cosmogenic origin in the upper troposphere and lower stratosphere (UT-LS) (Lal and Peters, 1967), 7 Be is considered a tracer for intrusion of stratospheric air into the troposphere and large-scale subsidence (e.g., Liu et al, 2016;Chae and Kim, 2019;Heikkila et al, 2008).…”