1 Basics: Proxies |APSC| and |VPSC|
2 ===================================
5 |APSC| specifies the area at a certain height, which is below a
6 typical temperature threshold below which the chlorine-catalyzed polar
7 ozone depletion takes place. |VPSC| is the corresponding volume in a
8 given height range (here: 14-22 km). Here the average value of this
9 size between mid December and the end of March is considered. Since
10 usually in cold arctic winters there is a stable polar vortex, it has
11 been found empirically that this quantity can provide good
12 approximations for ozone depletion [#]_. High values of [VPSC] mean
16 .. |APSC| replace:: A\ :sub:`PSC`\
17 .. |VPSC| replace:: V\ :sub:`PSC`\
18 .. |H2O| replace:: H\ :sub:`2`\ O
19 .. [#] see e.g. Rex, M. et al., Geophys. Res. Lett., 31, doi:10.1029/2003GL018844, 2004