A one hour integrated flask sampling system to collect air in automatedNOAA/ESRL 12-flask packages is described. The integrating compressor systemuses a mass flow controller to regulate the flow of air through a 15 lvolume, thus providing a mixture of air collected over an hour-long period.By beginning with a high flow rate of 3.8 standard liters per minute andgradually decreasing the flow rate over time to 0.29 standard liters perminute it is possible to obtain a nearly uniformly time averaged sample ofair and collect it into a pressurized 0.7 l flask. The weightingfunction determining the air mixture obtained is described in detail.Laboratory and field tests demonstrate that the integrated sampleapproximates a simple mean of air collected during the one-hour samplingtime.
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