Extreme events in total ozone over Arosa – Part 2: Fingerprints of atmospheric dynamics and chemistry and effects on mean values and long-term changes

Rieder, Harald E.; Staehelin, J.; Maeder, J. A.; Peter, Thomas; Ribatet, Mathieu; Davison, A. C.; Stübi, René; Weihs, Philipp; Holawe, F.

doi:10.5194/acp-10-10033-2010

Cited by 34 publications

(59 citation statements)

References 78 publications

(127 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our AMM analysis finds a significant contribution of ENSO to Boulder (US) ozone variability for PC score 3 (where ozone is maximum), which is similar to the result of Rieder et al (2010) analysis that also found a positive contribution over the US region. Note that the contribution is significant only for Winter and Spring months.…”

Section: Figsupporting

confidence: 77%

“…Thirdly, we compare our analysis with the analysis of total ozone data in Rieder et al (2010) and Rieder et al (2013). Our AMM analysis finds a significant contribution of ENSO to Boulder (US) ozone variability for PC score 3 (where ozone is maximum), which is similar to the result of Rieder et al (2010) analysis that also found a positive contribution over the US region.…”

Section: Figsupporting

confidence: 73%

“…The linear trend (and associated standard error) for 1980-1990 is −1.2 % (±0.4 %), for 1990-2000 it is −1.3 % (±0.4 %), and for 2000-2010 it is −1.1 % (±0.4 %). The linear trends for TO at Arosa from Rieder et al (2010), see their Table 3, are not as negative as those found here. For the only overlapping period of 1980-1990, the trend is −0.9 % (±0.3 %) per decade when extreme events are excluded.…”

Section: Estimated Trends For Total Column Ozonesupporting

confidence: 47%

“…In order to improve the fit, it is important to study dynamical processes to find their effects on long-term changes in ozone distribution in middle latitudes and in the upper stratosphere. Several studies have addressed the significance of contributions of dynamical processes to long-term ozone changes (Appenzeller et al, 2000;Weiss et al, 2001;Wohltmann et al, 2007;Mäder et al, 2007;Rieder et al, 2010;Frossard et al, 2013;Rieder et al, 2013;Nair et al, 2013). Several papers (Harris et al, 2008;WMO, 2007) found that a significant part of the change in total ozone after the middle of the 1990s and until 2005 was caused by dynamical variability.…”

Section: Atmosmentioning

confidence: 99%

See 3 more Smart Citations

Trends in stratospheric ozone profiles using functional mixed models

2013

View full text Add to dashboard Cite

Abstract. This paper is devoted to the modeling of altitudedependent patterns of ozone variations over time. Umkehr ozone profiles (quarter of Umkehr layer) from 1978 to 2011 are investigated at two locations: Boulder (USA) and Arosa (Switzerland). The study consists of two statistical stages. First we approximate ozone profiles employing an appropriate basis. To capture primary modes of ozone variations without losing essential information, a functional principal component analysis is performed. It penalizes roughness of the function and smooths excessive variations in the shape of the ozone profiles. As a result, data-driven basis functions (empirical basis functions) are obtained. The coefficients (principal component scores) corresponding to the empirical basis functions represent dominant temporal evolution in the shape of ozone profiles. We use those time series coefficients in the second statistical step to reveal the important sources of the patterns and variations in the profiles. We estimate the effects of covariates -month, year (trend), quasibiennial oscillation, the solar cycle, the Arctic oscillation, the El Niño/Southern Oscillation cycle and the Eliassen-Palm flux -on the principal component scores of ozone profiles using additive mixed effects models. The effects are represented as smooth functions and the smooth functions are estimated by penalized regression splines. We also impose a heteroscedastic error structure that reflects the observed seasonality in the errors. The more complex error structure enables us to provide more accurate estimates of influences and trends, together with enhanced uncertainty quantification. Also, we are able to capture fine variations in the time evolution of the profiles, such as the semi-annual oscillation. We conclude by showing the trends by altitude over Boulder and Arosa, as well as for total column ozone. There are great variations in the trends across altitudes, which highlights the benefits of modeling ozone profiles.

show abstract

Section: Figsupporting

confidence: 77%

Section: Figsupporting

confidence: 73%

Section: Estimated Trends For Total Column Ozonesupporting

confidence: 47%

Section: Atmosmentioning

confidence: 99%

See 2 more Smart Citations

Trends in stratospheric ozone profiles using functional mixed models

2013

View full text Add to dashboard Cite

show abstract

“…Finally ozone is affected negatively by high values of geopotential height at 500 hPa in southern midlatitudes and northern mid-to high latitudes. The importance of synoptic-scale meteorological variability in understanding extratropical total ozone column variability has long been recognized (e.g., Harris et al, 2008;Kiesewetter et al, 2010;Rieder et al, 2010).…”

Section: Discussionmentioning

confidence: 99%

Spatial regression analysis on 32 years of total column ozone data

Knibbe

Laat

2014

Atmos. Chem. Phys.

View full text Add to dashboard Cite

Abstract. Multiple-regression analyses have been performed on 32 years of total ozone column data that was spatially gridded with a 1 × 1.5 • resolution. The total ozone data consist of the MSR (Multi Sensor Reanalysis; 1979-2008 and 2 years of assimilated SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) ozone data (2009)(2010). The two-dimensionality in this data set allows us to perform the regressions locally and investigate spatial patterns of regression coefficients and their explanatory power. Seasonal dependencies of ozone on regressors are included in the analysis.A new physically oriented model is developed to parameterize stratospheric ozone. Ozone variations on nonseasonal timescales are parameterized by explanatory variables describing the solar cycle, stratospheric aerosols, the quasibiennial oscillation (QBO), El Niño-Southern Oscillation (ENSO) and stratospheric alternative halogens which are parameterized by the effective equivalent stratospheric chlorine (EESC). For several explanatory variables, seasonally adjusted versions of these explanatory variables are constructed to account for the difference in their effect on ozone throughout the year. To account for seasonal variation in ozone, explanatory variables describing the polar vortex, geopotential height, potential vorticity and average day length are included. Results of this regression model are compared to that of a similar analysis based on a more commonly applied statistically oriented model. The physically oriented model provides spatial patterns in the regression results for each explanatory variable. The EESC has a significant depleting effect on ozone at midand high latitudes, the solar cycle affects ozone positively mostly in the Southern Hemisphere, stratospheric aerosols affect ozone negatively at high northern latitudes, the effect of QBO is positive and negative in the tropics and mid-to high latitudes, respectively, and ENSO affects ozone negatively between 30 • N and 30 • S, particularly over the Pacific. The contribution of explanatory variables describing seasonal ozone variation is generally large at mid-to high latitudes. We observe ozone increases with potential vorticity and day length and ozone decreases with geopotential height and variable ozone effects due to the polar vortex in regions to the north and south of the polar vortices.Recovery of ozone is identified globally. However, recovery rates and uncertainties strongly depend on choices that can be made in defining the explanatory variables. The application of several trend models, each with their own pros and cons, yields a large range of recovery rate estimates. Overall these results suggest that care has to be taken in determining ozone recovery rates, in particular for the Antarctic ozone hole.

show abstract

Total ozone and Umkehr observations at Hoher Sonnblick 1994–2011: Climatology and extreme events

2014

View full text Add to dashboard Cite

Umkehr and total ozone measurements have been carried out at Hoher Sonnblick (47.05°N, 12.95°E; 3106 m above sea level) since 1994 with the Brewer MkIV #093 spectrophotometer. These measurements are used to investigate trends in total and vertically resolved ozone in the period 1994–2011 and for establishing an Umkehr climatology. A method to estimate daily thresholds for extreme events in total ozone (TO3) based on skewed log‐Weibull distributions is presented and applied to the record. An analysis of the such defined extreme events reveals a significant decline in the number of low events, whereas the high events increased by about the same amount. However, no significant trend is observed in the magnitude of extreme events. Solar activity and equivalent effective stratospheric chlorine show weak to no correlation with vertically resolved ozone, presumably due to the record's limited extent, while tropopause pressure and quasi‐biennial oscillation show a significant influence. Trend analysis of total and vertically resolved ozone indicates a significant increase in TO3 of 2.0% per decade since 1994, whereas no recovery is observed in the upper stratosphere. While ozone concentrations continue to decrease or stagnate in the upper stratosphere, the loss is overcompensated by large gains in the lowest layers during winter, leading to a significant overall increase in TO3. During events with extremely low TO3, the largest deficiencies are found in the bottommost layers with a marked seasonal component. The topmost layers mainly contribute to TO3 reductions during late winter and fall.

show abstract

Extreme events in total ozone over Arosa – Part 2: Fingerprints of atmospheric dynamics and chemistry and effects on mean values and long-term changes

Cited by 34 publications

References 78 publications

Trends in stratospheric ozone profiles using functional mixed models

Trends in stratospheric ozone profiles using functional mixed models

Spatial regression analysis on 32 years of total column ozone data

Total ozone and Umkehr observations at Hoher Sonnblick 1994–2011: Climatology and extreme events

Contact Info

Product

Resources

About