An assessment of ECC ozonesondes operated using 1% and 0.5% KI cathode solutions at Lauder, New Zealand

The effects of reducing the concentration of the potassium iodide (KI) cathode electrolyte from 1% to 0.5% in electrochemical concentration cell (ECC) ozonesondes flown at Lauder, New Zealand (45° S, 170° E) have been investigated. Four studies were made to assess these effects: 1% and 0.5% KI ozonesonde performance was compared directly in three dual flights, one year of 1% KI and one year of 0.5% KI ozonesonde profiles were compared with near‐simultaneous lidar profiles, integrated ozonesonde profiles were compared with Dobson spectrophotometer measurements over the same period, and ascent and descent profiles were compared for both KI concentrations. Ozonesondes flown with a 1% KI solution showed positive differences of 3% to 8% in the ozone profile and ∼5% in the ozone column compared with the 0.5% KI ozonesondes, which also showed better agreement in profiles and ozone column compared with the lidar and Dobson spectrophotometer measurements respectively.