10/21/09

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Range-corrected signal

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The mid-tropospheric ozone increases relative to the 10/19 data. This might be contributed by two factors: downward transport (strong STE on 10/17 sonde profile) and warmer temperature. But the lower-tropospheric ozone still maintains at a low level.

Note the ceilometer data only updated to 18:00GMT (13:00LT)