Seasonal prediction of US summertime ozone using statistical analysis of large scale climate patterns

Abstract

We develop a statistical model to predict June-July-August (JJA) daily maximum 8-h average (MDA8) ozone concentrations in the eastern United States based on large-scale climate patterns during the previous spring. We find that anomalously high JJA ozone in the East is correlated with these springtime patterns: warm tropical Atlantic and cold northeast Pacific sea surface temperatures (SSTs), as well as positive sea level pressure (SLP) anomalies over Hawaii and negative SLP anomalies over the Atlantic and North America. We then develop a linear regression model to predict JJA MDA8 ozone from 1980 to 2013, using the identified SST and SLP patterns from the previous spring. The model explains ∼45% of the variability in JJA MDA8 ozone concentrations and ∼30% variability in the number of JJA ozone episodes (>70 ppbv) when averaged over the eastern United States. This seasonal predictability results from large-scale ocean-atmosphere interactions. Warm tropical Atlantic SSTs can trigger diabatic heating in the atmosphere and influence the extratropical climate through stationary wave propagation, leading to greater subsidence, less precipitation, and higher temperatures in the East, which increases surface ozone concentrations there. Cooler SSTs in the northeast Pacific are also associated with more summertime heatwaves and high ozone in the East. On average, models participating in the Atmospheric Model Intercomparison Project fail to capture the influence of this ocean-atmosphere interaction on temperatures in the eastern United States, implying that such models would have difficulty simulating the interannual variability of surface ozone in this region.ozone | seasonal forecast | teleconnection | sea surface temperature

Scientific assessment of background ozone over the U.S.: Implications for air quality management

“…Large-scale variations in temperature, pressure, and airflow can also lead to substantial year-to-year variations in O 3 production, air mass stagnation, snowpack accumulation, and wildfire severity (Fiore et al, 2015;Mote et al, 2016;Gong et al, 2017;Jaffe and Zhang., 2017;Lin et al, 2017;Shen and Mickley, 2017). Interannual variability of surface O 3 in the Intermountain West during summer is found to correlate with wildfire severity (Jaffe, 2011;Jaffe et al, 2008).…”

Connections between summer air pollution and stagnation

“…Barnes and Fiore 2013, Shen et al 2015, Otero et al 2016, teleconnection patterns (e.g. Shen and Mickley 2017), and distribution of anthropogenic precursor emissions (e.g. He et al 2013a) which have been shown to influence surface-level pollution.…”

How waviness in the circulation changes surface ozone: a viewpoint using local finite-amplitude wave activity

“…It can be used to differentiate longitudinally isolated events and to characterize local and regional weather (Huang and Nakamura, 2016). Shen and Mickley (2017b) note the connection between the eastwardpropagating flux in wave activity associated with the Pacific extreme pattern and increased surface pressure, reduced precipitation, warmer temperatures, more frequent heat waves, and enhanced ozone over the eastern US. A diagnosis of LWA also provides a metric for the occurrence of blocking events, events associated with anomalous or extreme midlatitude weather such as heat waves Martineau et al, 2017), which have been associated with surface ozone extremes (e.g., Sun et al, 2017;Meehl et al, 2018;Phalitnonkiat et al, 2018).…”