Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

IF value: 5.414
IF 5-year value: 5.958
IF 5-year
CiteScore value: 9.7
SNIP value: 1.517
IPP value: 5.61
SJR value: 2.601
Scimago H <br class='widget-line-break'>index value: 191
Scimago H
h5-index value: 89
Volume 15, issue 3
Atmos. Chem. Phys., 15, 1585–1598, 2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
Atmos. Chem. Phys., 15, 1585–1598, 2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.

Research article 13 Feb 2015

Research article | 13 Feb 2015

The influence of the North Atlantic Oscillation and El Niño–Southern Oscillation on mean and extreme values of column ozone over the United States

I. Petropavlovskikh1, R. Evans2, G. McConville1, G. L. Manney3,4, and H. E. Rieder5,6 I. Petropavlovskikh et al.
  • 1Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309, USA
  • 2NOAA Earth System Research Laboratory, Boulder, CO 80305, USA
  • 3NorthWest Research Associates, Socorro, NM 87801, USA
  • 4Department of Physics, New Mexico Institute of Mining and Technology, Socorro, NM 87801, USA
  • 5Wegener Center for Climate and Global Change and IGAM/Institute of Physics, University of Graz, 8010 Graz, Austria
  • 6Lamont–Doherty Earth Observatory of Columbia University, Palisades, NY 10964, USA

Abstract. Continuous measurements of total ozone (by Dobson spectrophotometers) across the contiguous United States began in the early 1960s. Here, we analyze temporal and spatial variability and trends in total ozone from the five US sites with long-term records. While similar long-term ozone changes are detected at all five sites, we find differences in the patterns of ozone variability on shorter timescales. In addition to standard evaluation techniques, STL-decomposition methods (Seasonal Trend decomposition of time series based on LOESS (LOcally wEighted Scatterplot Smoothing)) are used to address temporal variability and "fingerprints" of dynamical features in the Dobson data. Methods from statistical extreme value theory (EVT) are used to characterize days with high and low total ozone (termed EHOs and ELOs, respectively) at each station and to analyze temporal changes in the frequency of ozone extremes and their relationship to dynamical features such as the North Atlantic Oscillation (NAO) and El Niño–Southern Oscillation. A comparison of the fingerprints detected in the frequency distribution of the extremes with those for standard metrics (i.e., the mean) shows that more fingerprints are found for the extremes, particularly for the positive phase of the NAO, at all five US monitoring sites. Results from the STL decomposition support the findings of the EVT analysis. Finally, we analyze the relative influence of low- and high-ozone events on seasonal mean column ozone at each station. The results show that the influence of ELOs and EHOs on seasonal mean column ozone can be as much as ±5 %, about as large as the overall long-term decadal ozone trends.

Publications Copernicus
Final-revised paper