The efficiency of the ECC-6A Ozonesonde air sampling pump decreases with altitude. Calculated ozone partial pressures must, therefore, be corrected for the efficiency loss. Correcting factors for ECC-6A pumps, with ECC sensor cathodes filled with 2.5 cm3 sensing solution and 3.0 cm3 sensing solution, are shown in the following table, respectively. At pressure level (P) the value of Cef is calculated using linear interpolation as a function of pressure.
| The ASOPOS panel recommends the use of 3.0 cm3 only. |
| Ozone partial pressure correction factor Cef | ||
|---|---|---|
| Atmospheric pressure hPa | Sensor cathode solution volume 2.5 cm3 | Sensor cathode solution volume 3.0 cm3 |
| 2.0 | 1.160 | 1.171 |
| 3.0 | 1.124 | 1.131 |
| 5.0 | 1.087 | 1.092 |
| 10.0 | 1.054 | 1.055 |
| 20.0 | 1.033 | 1.032 |
| 30.0 | 1.024 | 1.022 |
| 50.0 | 1.015 | 1.015 |
| 100.0 | 1.010 | 1.011 |
| 200.0 | 1.007 | 1.008 |
| 300.0 | 1.005 | 1.006 |
| 500.0 | 1.002 | 1.004 |
| 1000.0 | 1.000 | 1.000 |
For other sensor manufacturers, the pump correction is very similar to the SPC ozone sensor, only the table values differ.
For Model Z, use the following table.
| P/hPa | Cef |
|---|---|
| ≤3 | 1.24 |
| 5 | 1.124 |
| 7 | 1.087 |
| 10 | 1.066 |
| 15 | 1.048 |
| 20 | 1.041 |
| 30 | 1.029 |
| 50 | 1.018 |
| 70 | 1.013 |
| 100 | 1.007 |
| 150 | 1.002 |
| ≥200 | 1 |