Geology Reference
In-Depth Information
Figure 32 The Winter vortex over Antarctica. The cold core is almost isolates from the
rest of the atmosphere, and acts as a reaction vessel in which chlorine activation
may take place in the polar night (after ref. 3)
ClONO
2
(g)
þ
H
2
O (ice)
-
HOCl (g)
þ
HNO
3
(ice)
(2.102)
HOCl (g)
þ
HCl (ice)
-
Cl
2
(g)
þ
H
2
O (ice)
(2.103)
N
2
O
5
(g)
þ
H
2
O (ice)
-
2HNO
3
(ice)
(2.104)
In reactions (2.101 and 2.102), the normally inactive reservoir for Cl and
ClO is converted into molecular chlorine. It is worth noting that the
HNO
3
is left in the ice-phase. These reactions can continue all winter
long without light converting inactive chlorine to active chlorine. The
two main effects therefore of the heterogeneous chemistry involving
