Table 2.
Summary of O3 concentration and zero-out contribution of emissions from the US and east Asia, and sensitivity of O3VORT over four time zones in the US during April 2010.
| O3 concentration | Emission impacts from the US | Emission impacts from east Asia | Impacts by stratospheric intrusion | |
|---|---|---|---|---|
| Pacific Standard Time (PST) | ||||
| – Surface | 35.8 | 3.2 | 2.8 | 0.2 |
| – Bottom of free troposphere | 47.3 | 2.7 | 6.1 | 0.7 |
| – Middle of free troposphere | 54.0 | 2.4 | 7.3 | 2.0 |
| – Top of free troposphere | 108.3 | 3.0 | 6.5 | 22.3 |
| Mountain Standard Time (MST) | ||||
| – Surface | 39.3 | 5.5 | 3.3 | 0.4 |
| – Bottom of free troposphere | 50.3 | 4.8 | 5.7 | 0.9 |
| – Middle of free troposphere | 54.8 | 2.7 | 7.2 | 2.2 |
| – Top of free troposphere | 119.7 | 3.3 | 6.4 | 28.3 |
| Central Standard Time (CST) | ||||
| – Surface | 39.1 | 9.2 | 2.1 | 0.2 |
| – Bottom of free troposphere | 50.9 | 6.6 | 4.9 | 0.6 |
| – Middle of free troposphere | 53.9 | 3.3 | 6.6 | 2.0 |
| – Top of free troposphere | 79.9 | 2.9 | 6.1 | 12.9 |
| Eastern Standard Time (EST) | ||||
| – Surface | 40.6 | 9.6 | 1.9 | 0.1 |
| – Bottom of free troposphere | 52.0 | 7.9 | 5.0 | 0.6 |
| – Middle of free troposphere | 53.2 | 3.9 | 6.2 | 2.0 |
| – Top of free troposphere | 78.9 | 3.4 | 6.0 | 12.8 |
Note: all units are ppbv.