Homing in on the missing sink.
that both produce and consume OH are of critical importance to an assessment of changes in the oxidizing power of the troposphere. This understanding is currently sketchy, in part, because instrumentation for measuring OH has only recently become available. A recognition of the current importance of tropospheric OH has played a critical role in environmental policy, notably in the replacement of chlorofluorocarbons with products amenable to oxidation by OH in the troposphere.