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CH3041
THE HYDROXYL
RADICAL II
Reactions:
• OH. + CºO ® HOC=O. ®
H. + CO2
addition
OH. + CH4 ®
H2O + CH3. abstraction
• OH. is the key
oxidant in the troposphere in both unpolluted and polluted
air (not O2).
• In the unpolluted troposphere 70% of the available
OH. reacts with CO (otherwise unreactive),
most of the rest reacts with CH4
• Production of OH. is linked to the solar
photon flux. For this reason
1) tropics have a higher local [OH.]
than the temperate regions and 2)
the [OH.] is low at night.
