Simulation of the record Arctic stratospheric ozone depletion in 2020

Grooß, Jens‐Uwe; Müller, Rolf

doi:10.1002/essoar.10503569.1

Cited by 10 publications

(17 citation statements)

References 56 publications

(86 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(As explained in the SI, the vortex‐averaged descent methods give slightly lower estimates than Match because they may be more affected by dilution of the chemical loss signature near the vortex edge.) Record‐low springtime O 3 at lower altitudes in 2020 than in 2011 is consistent with evidence of record‐low total column O 3 (Grooß & Müller, 2020; Wohltmann et al., 2020) and anomalously high surface ultraviolet in 2020 (Bernhard et al., 2020). Large interannual variability in meteorological conditions in the Arctic stratosphere (which led to the exceptionally strong and long‐lived polar vortex in 2019/2020) may yet result in more extreme Arctic O 3 loss in future years while stratospheric chlorine loading remains high: For instance, 2015/2016 still stands out as the coldest Arctic winter with most denitrification and dehydration—if conditions such as those commenced as early in some future year and lasted as late as in 2019/2020, and the vortex remained well‐isolated, then greater O 3 depletion could occur.…”

Section: Discussionsupporting

confidence: 80%

“…Thus, HCl production was highly favored inside the persistently cold, strongly denitrified, and ozone-depleted Arctic vortex in spring 2020. Atmospheric Chemistry Experiment-Fourier Transform Spectrometer ClONO 2 data (Boone et al, 2013) ( Figure S6 and Text S4) and model results (Grooß & Müller, 2020) are consistent with this picture.…”

Section: Discussionsupporting

confidence: 70%

“…Match estimates suggest more chemical loss in December 2019 through April 2020 than in 2010/2011 below ∼460 K; peak losses were near 2.8 ppmv in each of these winters, but at lower altitude in 2020 than in 2011. While empirical O 3 loss estimates have large uncertainties (e.g., Griffin et al., 2019; also see SI), vortex‐averaged descent calculations using MLS N 2 O (overlaid lines/symbols in Figures 4f and 4l) and using trajectory‐based descent rates (overlaid symbols in Figure 4) (see SI for description of calculations) give consistent results; Grooß and Müller (2020) and Wohltmann et al. (2020) report similar results using different data sets and methods.…”

Section: Discussionmentioning

confidence: 74%

See 2 more Smart Citations

Record‐Low Arctic Stratospheric Ozone in 2020: MLS Observations of Chemical Processes and Comparisons With Previous Extreme Winters

Manney

Livesey

Santee

et al. 2020

Geophysical Research Letters

120

148

View full text Add to dashboard Cite

Aura Microwave Limb Sounder (MLS) measurements show that chemical processing was critical to the observed record‐low Arctic stratospheric ozone in spring 2020. The 16‐year MLS record indicates more polar denitrification and dehydration in 2019/2020 than in any Arctic winter except 2015/2016. Chlorine activation and ozone depletion began earlier than in any previously observed winter, with evidence of chemical ozone loss starting in November. Active chlorine then persisted as late into spring as it did in 2011. Empirical estimates suggest maximum chemical ozone losses near 2.8 ppmv by late March in both 2011 and 2020. However, peak chlorine activation, and thus peak ozone loss, occurred at lower altitudes in 2020 than in 2011, leading to the lowest Arctic ozone values ever observed at potential temperature levels from ∼400–480 K, with similar ozone values to those in 2011 at higher levels.

show abstract

Section: Discussionsupporting

confidence: 80%

Section: Discussionsupporting

confidence: 70%

Section: Discussionmentioning

confidence: 74%

See 1 more Smart Citation

Record‐Low Arctic Stratospheric Ozone in 2020: MLS Observations of Chemical Processes and Comparisons With Previous Extreme Winters

Manney

Livesey

Santee

et al. 2020

Geophysical Research Letters

120

148

View full text Add to dashboard Cite

show abstract

“…Stratospheric ozone values over large parts of the Arctic reached record low values in March and April 2020 (Manney et al, 2020) with ozone severely depleted between mid-March and mid-April 2020 when ozonesondes observed minimum mixing ratios of 0.1-0.2 ppm around 17-19 km (Wohltmann et al, 2020), lower than observed in any previous year. Model simulations and evaluation against MLS data by Groß and Müller (2020) also confirmed these findings. The last time similarly low ozone columns were observed over the Arctic was during boreal spring 2011 (Manney et al, 2011) and 1997 (Newman et al, 1997).…”

Section: Introductionsupporting

confidence: 54%

Exceptionally Low Arctic Stratospheric Ozone in Spring 2020 as Seen in the CAMS Reanalysis

et al. 2020

View full text Add to dashboard Cite

A reanalysis data set produced by the Copernicus Atmosphere Monitoring service (CAMS reanalysis, 2003 to present day) augmented by ERA5 data for the years before 2003 is used to describe the evolution of the 2020 Arctic ozone season and to compare it with years back to 1979. Ozone columns over large parts of the Arctic reached record low values in March and April 2020 because of an exceptionally strong, cold, and persistent Arctic polar vortex. Minimum ozone columns were below 250 DU for most of March and the first half of April, with the lowest values of 211 DU in the CAMS reanalysis found on 18 March. Such low values are extremely unusual for the Arctic. The previous years with similarly strong Arctic ozone depletion were 2011 and 1997 with minimum values of 232 and 217 DU, respectively. The performance of the CAMS ozone analysis is assessed by comparison with ozonesonde data and found to agree well with the independent observations. We find a clear sign of chemical ozone destruction with ozone severely depleted in a layer between 80 and 50 hPa in late March and early April when partial pressure values below 2 mPa were observed. Profiles from the limb sounders Atmospheric Chemistry Experiment‐Fourier Transform Spectrometer (ACE‐FTS) and Microwave Limb Sounder (MLS) show clear signs of chlorine activation and the presence of polar stratospheric clouds. Monthly mean ozone columns in March 2020 were up to 180 DU or 40% lower than the CAMS climatology (2003–2019) while values for 2011 and 1997 were lower by 31% and 35%, respectively.

show abstract

“…(2020, published in this special collection) use observations of relevant chemical species from the Aura Microwave Limb Sounder to illustrate the chemical and transport processes leading to exceptional chemical ozone loss and record low ozone by spring 2020. Other studies presently submitted for this special collection and elsewhere further explore the detailed evolution of ozone during the season using a variety of measurements and models (Dameris et al, 2020; Grooß & Müller, 2020; Inness et al, 2020; Wohltmann et al, 2020), and more are in preparation. Were there downstream impacts related to the strong vortex, ozone deficit, and persistent positive tropospheric AO events? The strong polar vortex, low ozone, and positive AO events that occurred in the late winter/early spring of 2020 were each record‐breaking on seasonal time scales, and as a result, there is a possibility they had farther‐reaching consequences.…”

Section: Discussionmentioning

confidence: 99%

The Remarkably Strong Arctic Stratospheric Polar Vortex of Winter 2020: Links to Record‐Breaking Arctic Oscillation and Ozone Loss

et al. 2020

View full text Add to dashboard Cite

The Northern Hemisphere (NH) polar winter stratosphere of 2019/2020 featured an exceptionally strong and cold stratospheric polar vortex. Wave activity from the troposphere during December-February was unusually low, which allowed the polar vortex to remain relatively undisturbed. Several transient wave pulses nonetheless served to help create a reflective configuration of the stratospheric circulation by disturbing the vortex in the upper stratosphere. Subsequently, multiple downward wave coupling events took place, which aided in dynamically cooling and strengthening the polar vortex. The persistent strength of the stratospheric polar vortex was accompanied by an unprecedentedly positive phase of the Arctic Oscillation in the troposphere during January-March, which was consistent with large portions of observed surface temperature and precipitation anomalies during the season. Similarly, conditions within the strong polar vortex were ripe for allowing substantial ozone loss: The undisturbed vortex was a strong transport barrier, and temperatures were low enough to form polar stratospheric clouds for over 4 months into late March. Total column ozone amounts in the NH polar cap decreased and were the lowest ever observed in the February-April period. The unique confluence of conditions and multiple broken records makes the 2019/2020 winter and early spring a particularly extreme example of two-way coupling between the troposphere and stratosphere. Plain Language Summary Wintertime westerly winds in the polar stratosphere (from ∼15-50 km), known as the stratospheric polar vortex, were extraordinarily strong during the Northern Hemisphere winter of 2019/2020. The exceptional strength of the stratospheric polar vortex had consequences for winter and early spring weather near the surface and for stratospheric ozone depletion. Typically atmospheric waves generated in the troposphere spread outward and upward into the stratosphere where they can disturb and weaken the polar vortex, but tropospheric wave activity was unusually weak during the 2019/2020 winter. In addition, an unusual configuration of the stratospheric polar vortex developed that reflected waves traveling upward from the troposphere back downward. These unique conditions allowed the vortex to remain strong and cold for several months. During January-March 2020, the strong stratospheric polar vortex was closely linked to a near-surface circulation pattern that resembles the positive phase of the so-called "Arctic Oscillation" (AO). This positive AO pattern was also of record strength and influenced the regional distributions of temperatures and precipitation during the late winter and early spring. Cold and stable conditions within the polar vortex also allowed strong ozone depletion to take place, leading to lower ozone levels than ever before seen above the Arctic in spring.

show abstract

Simulation of the record Arctic stratospheric ozone depletion in 2020

Cited by 10 publications

References 56 publications

Record‐Low Arctic Stratospheric Ozone in 2020: MLS Observations of Chemical Processes and Comparisons With Previous Extreme Winters

Record‐Low Arctic Stratospheric Ozone in 2020: MLS Observations of Chemical Processes and Comparisons With Previous Extreme Winters

Exceptionally Low Arctic Stratospheric Ozone in Spring 2020 as Seen in the CAMS Reanalysis

The Remarkably Strong Arctic Stratospheric Polar Vortex of Winter 2020: Links to Record‐Breaking Arctic Oscillation and Ozone Loss

Contact Info

Product

Resources

About