Relationship between the North Atlantic Oscillation and Trans-Atlantic Pollution Transport
Creilson et al. [2003] examined the seasonal and regional distribution of tropospheric ozone across the North Atlantic and its relationship to the North Atlantic Oscillation (NAO) as a possible transport mechanism across the North Atlantic. The study found distinct springtime interannual variability over the North Atlantic in the TOR fields that is correlated with the interannual variability of the NAO. Positive phases of the NAO are indicative of a stronger Bermuda/Azores high and a stronger Icelandic low and thus faster more zonal flow across the North Atlantic from west to east. This flow regime appears to be causing the transport of tropospheric ozone across the North Atlantic and onto Europe. An example of the highly variable nature of the TOR over Europe and the flow patterns that usually accompany these patterns is provided in Figure 11. The entire article is found at Creilson et al. [2003].

Arctic Oscillation-induced variability in satellite-derived tropospheric ozone
Creilson et al. [2005] showed that there is a statistically significant correlation between the Arctic Oscillation (AO) and the springtime tropospheric ozone distribution over the northeastern Atlantic, but not over the Pacific. This finding is consistent with our understanding of the differing effect that the AO has on the Atlantic versus Pacific basins and the strong influence that the El Niño phenomenon has in the Pacific. The insight gained from this study contributes to the growing use of teleconnections as a forecast tool, providing insight into the interaction between prevailing meteorological conditions and the formation of significant pollution events. On the other hand, correlations across the Pacific were stronger with the Southern Oscillation Index (SOI) than with the AO. An analysis of the 500 hPa flow patterns across the North Pacific shows that the core of the strongest anomalies are located to the north of our study area and also to the south where the influence of ENSO is strongest, suggesting that enhanced tropospheric ozone in the eastern Pacific/western United States is due to a different set of processes and relationships. These findings are summarized in Figure 12; the complete discussion can be found in Creilson et al. [2005] [PDF].

Interannual Variability of Stratospheric and Tropospheric Ozone
Fishman et al. [2005] show that the interannual variability (IAV) of the stratospheric column ozone (SCO) from the TOR data base is consistent with previous findings for total ozone that show a strong correlation with the quasi-biennial oscillation (QBO) at low latitudes (Figure 13). For tropospheric ozone, there are strong regional enhancements due to in situ generation from large emissions (Figure 14); the IAV of some of these regional enhancements, on the other hand, are strongly correlated with the phase of El Niño/Southern Oscillation (ENSO) and are consistent with our understanding of how regions of subsidence are more conducive to the in situ production of ozone pollution (Figure 15). The insight gained from these analyses will hopefully provide a better understanding between prevailing meteorological conditions and the evolution of widespread ozone episodes on shorter time scales with the eventual goal of producing an air quality forecasting capability so that exposure of the human population to elevated levels of ozone can be reduced. The complete paper has been published as Fishman et al. [2005] [PDF].

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