Page 226 - Materials Chemistry, Second Edition

212 R.K. Rosenbaum et al.

CFC ClONO 2
O NO 2

Cl• ClO•

O 2 +O
O 3
Strong UV light

Fig. 10.11 Degradation of ozone catalysed by chlorine in the stratosphere (simplified)

Fig. 10.12 Impact pathway
Halocarbon
for stratospheric ozone
emissions
depletion (CFCs, HCFCs, N 2 O
Halons) emissions
Depletion of
stratospheric ozone by
catalysed cleavage

Decreased
abundance of
stratospheric ozone

Increased UVB
radiation intensity
at Earth’s surface

Damage to
Damage to human ecosystems
health
(terrestrial vegetation,
(skin cancer, cataract, phytoplankton,
immune system production of wood,
depression)
crop and fish)