Ozone is measured with a compact and lightweight 2B Technologies, Inc. Model 205 Ozone Monitor as the platform base. The 2B ozone instrument uses the ultraviolet (UV) absorption method to measure ozone concentrations (accurate to 1 ppbv or 2% of reading). The instrument records 2-second measurement data at 10-second intervals to give a dynamic view of the vertical profiling of ozone in the lower atmosphere. Temperature and relative humidity has been added to the data stream, due to the inclusion of a Vaisala Temperature and Humidity probe and a Garmin GPS receiver.
Ozone Instrument Details
Ozone absorption measurements take place every two seconds in the ozone monitor although we record data averages over 10 seconds. Air, after traveling into the inlet and through a Teflon particle filter, is pulled through an ozone scrubber for every other measurement. This “zero” reference measurement, alternates between Cell 1 and Cell 2. A mercury lamp illuminates these cells and at the opposite end of each cell is a detector that makes a measurement of light that has not been absorbed by ozone. A flowmeter has been installed to monitor instrument flow, as flow through the cells must remain at approximately 1L/min.
Additional components installed in the suitcase include a fan, strip heaters, a flash card data writer, a 12-V rechargeable battery, a micro-SD backup data writer, Vaisala Temperature and Humidity probe, Garmin GPS receiver, and an additional zero cycle (to calculate instrument drift).