Increasing background ozone in surface air over the United States

Lin, Chuan-Yao; Jacob, Daniel J.; Munger, J. William; Fiore, Arlene M.

doi:10.1029/2000gl011762

Cited by 91 publications

(9 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While peak ozone concentrations have decreased in the eastern U.S. during the ozone season, some sites also show increases in ozone at the low end of the distribution [Lefohn et al, 2010;Cooper et al, 2012] that may be due to reduced titration by NO or to increases in baseline ozone [Lin et al, 2000;Cooper et al, 2012], which is the ozone observed at sites without the presence of recent local pollution influence [Dentener et al, 2010]. A modeling study by Fiore et al [2002] found increases in ozone between 1980 and 1995 at the lower half of the distribution due to increases in Asian emissions.…”

mentioning

confidence: 89%

Trends and variability in surface ozone over the United States

et al. 2015

View full text Add to dashboard Cite

We investigate the observed trends and interannual variability in surface ozone over the United States using the Global Modeling Initiative chemical transport model. We discuss the roles of meteorology, emissions, and transport from the stratosphere in driving the interannual variability in different regions and seasons. We demonstrate that a hindcast simulation for 1991-2010 can reproduce much of the observed variability and the trends in summertime ozone, with correlation coefficients for seasonally and regionally averaged median ozone ranging from 0.46 to 0.89. Reproducing the interannual variability in winter and spring in the western United States may require higher-resolution models to adequately represent stratosphere-troposphere exchange. Hindcast simulations with fixed versus variable emissions show that changes in anthropogenic emissions drive the observed negative trends in monthly median ozone concentrations in the eastern United States during summer, as well as the observed reduction in the amplitude of the seasonal cycle. The simulation underestimates positive trends in the western United States during spring, but excluding the first 4 years of data removes many of the statistically significant trends in this region. The reduction in the slope of the ozone versus temperature relationship before and after major emission reductions is also well represented by the model. Our results indicate that a global model can reproduce many of the important features of the meteorologically induced ozone variability as well as the emission-driven trends, lending confidence to model projections of future changes in regional surface ozone.

show abstract

mentioning

confidence: 89%

Trends and variability in surface ozone over the United States

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The term "background" was used in modeling studies that estimated the atmospheric mixing ratio of a compound determined by natural sources only, while the term "baseline" was obtained from measurement records by removing data affected by local influences (Chan and Vet, 2010). Various methods have been utilized to diagnose baseline conditions, including using measurements at remote sites, analysis of the probability distribution of pollutants, correlations with reactive nitrogen oxides, or isentropic back-trajectories (e.g., Lin et al, 2000;Derwent et al, 2007;Wilson et al, 2012). Air masses with monthly to annual low percentile values of CO are commonly considered baseline air (e.g., Lin et al, 2000;Mao and Talbot, 2012).…”

Section: Introductionmentioning

confidence: 99%

Regional and hemispheric influences on temporal variability in baseline carbon monoxide and ozone over the Northeast US

Mao

Demerjian

Hogrefe

et al. 2017

Atmospheric Environment

View full text Add to dashboard Cite

Interannual variability in baseline carbon monoxide (CO) and ozone (O), defined as mixing ratios under minimal influence of recent and local emissions, was studied for seven rural sites in the Northeast US over 2001 - 2010. Annual baseline CO exhibited statistically significant decreasing trends (-4.3 - -2.3 ppbv yr), while baseline O did not display trends at any site. In examining the data by season, wintertime and springtime baseline CO at the two highest sites (1.5 km and 2 km asl) did not experience significant trends. Decadal increasing trends (~2.55 ppbv yr) were found in springtime and wintertime baseline O in southern New Hampshire, which was associated with anthropogenic NO emission reductions from the urban corridor. Biomass burning emissions impacted summertime baseline CO with ~38% variability from wildfire emissions in Russia and ~22% from Canada at five sites and impacted baseline O at the two high elevation sites only with ~27% variability from wildfires in both Russia and Canada. The Arctic Oscillation was negatively correlated with summertime baseline O, while the North Atlantic Oscillation was positively correlated with springtime baseline O. This study suggested that anthropogenic and biomass burning emissions, and meteorological conditions were important factors working together to determine baseline O and CO in the Northeast U.S. during the 2000s.

show abstract

“…The PRB is an important factor in the NAAQS-setting process, as it represents a baseline of risk not amenable to domestic regulation [U.S. EPA, 2006]. Model studies indicate that the PRB background has a large intercontinental anthropogenic component [Fiore et al, 2002a[Fiore et al, , 2003a and observations show that it has been rising over the past three decades [Lin et al, 2000;Jaffe et al, 2003].…”

Section: Introductionmentioning

confidence: 99%

Effects of 2000–2050 changes in climate and emissions on global tropospheric ozone and the policy‐relevant background surface ozone in the United States

et al. 2008

Self Cite

View full text Add to dashboard Cite

We use a global chemical transport model (GEOS‐Chem) driven by a general circulation model (NASA Goddard Institute for Space Studies GCM) to investigate the effects of 2000–2050 global change in climate and emissions (the Intergovernmental Panel on Climate Change A1B scenario) on the global tropospheric ozone budget and on the policy‐relevant background (PRB) ozone in the United States. The PRB ozone, defined as the ozone that would be present in U.S. surface air in the absence of North American anthropogenic emissions, has important implications for setting national air quality standards. We examine separately and then together the effects of changes in climate and anthropogenic emissions of ozone precursors. We find that the 2000–2050 change in global anthropogenic emissions of ozone precursors increases the global tropospheric ozone burden by 17%. The 2000–2050 climate change increases the tropospheric ozone burden by 1.6%, due mostly to lightning in the upper troposphere, and also increases global tropospheric OH by 12%. In the lower troposphere, by contrast, climate change generally decreases the background ozone. The 2000–2050 increase in global anthropogenic emissions of ozone precursors increases PRB ozone by 2–6 ppb in summer; the maximum effect is found in April (3–7 ppb). The summertime PRB ozone decreases by up to 2 ppb with 2000–2050 climate change, except over the Great Plains, where it increases slightly as a result of increasing soil NOx emission. Climate change cancels out the effect of rising global anthropogenic emissions on the summertime PRB ozone in the eastern United States, but there is still a 2–5 ppb increase in the west.

show abstract

Increasing background ozone in surface air over the United States

Cited by 91 publications

References 17 publications

Trends and variability in surface ozone over the United States

Trends and variability in surface ozone over the United States

Regional and hemispheric influences on temporal variability in baseline carbon monoxide and ozone over the Northeast US

Effects of 2000–2050 changes in climate and emissions on global tropospheric ozone and the policy‐relevant background surface ozone in the United States

Contact Info

Product

Resources

About