scholarly journals The potential impact of ClO<sub>x</sub> radical complexes on polar stratospheric ozone loss processes

2006 ◽  
Vol 6 (10) ◽  
pp. 3099-3114 ◽  
Author(s):  
B. Vogel ◽  
W. Feng ◽  
M. Streibel ◽  
R. Müller
Keyword(s):  
Equilibrium Constant ◽  
Stratospheric Ozone ◽  
Potential Temperature ◽  
The Arctic ◽  
Dimer Formation ◽  
Model Simulations ◽  
Ozone Loss ◽  
Radical Complex ◽  
Potential Impact ◽  
Complex Chemistry

Abstract. The importance of radical-molecule complexes for atmospheric chemistry has been discussed in recent years. In particular, the existence of a ClO·O2 and ClOx water radical complexes like ClO·H2O, OClO·H2O, OClO·(H2O)2, and ClOO·H2O could play a role in enhancing the ClO dimer (Cl2O2) formation and therefore may constitute an important intermediate in polar stratospheric ozone loss cycles. Model simulations performed with the Chemical Lagrangian Model of the Stratosphere (CLaMS) will be presented to study the role of radical complexes on polar stratospheric ozone loss processes. The model simulations are performed for the Arctic winter 2002/2003 at a level of 500 K potential temperature and the results are compared to observed ozone loss rates determined by the Match technique. Moreover, recently reported values for the equilibrium constant of the ClO dimer formation are used to restrict the number of possible model results caused by large uncertainties about radical complex chemistry. Our model simulations show that the potential impact of ClO·O2 on polar ozone loss processes is small (dO3/dt≪0.5 ppb/sunlight h) provided that the ClO·O2 complex is only weakly stable. Assuming that the binding energies of the ClOx water complexes are much higher than theoretically predicted an enhancement of the ozone loss rate by up to ≈0.5 ppb/sunlight h is simulated. Because it is unlikely that the ClOx water complexes are much more stable than predicted we conclude that these complexes have no impact on polar stratospheric ozone loss processes. Although large uncertainties about radical complex chemistry exist, our findings show that the potential impact of ClOx radical molecule complexes on polar stratospheric ozone loss processes is very small considering pure gas-phase chemistry. However the existence of ClOx radical-molecule complexes could possibly explain discrepancies for the equilibrium constant of the ClO dimer formation found between recent laboratory and stratospheric measurements.

scholarly journals The potential impact of ClO<sub>x</sub> radical complexes on polar stratospheric ozone loss processes

2006 ◽  
Vol 6 (1) ◽  
pp. 981-1022
Author(s):  
B. Vogel ◽  
W. Feng ◽  
M. Streibel ◽  
R. Müller
Keyword(s):  
Equilibrium Constant ◽  
Stratospheric Ozone ◽  
Potential Temperature ◽  
The Arctic ◽  
Dimer Formation ◽  
Model Simulations ◽  
Ozone Loss ◽  
Radical Complex ◽  
Potential Impact ◽  
Complex Chemistry

Abstract. The importance of radical-molecule complexes for atmospheric chemistry has been discussed in recent years. In particular, the existence of a ClO·O2 and ClOx water radical complexes like ClO·H2O, OClO·H2O, OClO·(H2O)2, and ClOO·H2O could play a role in enhancing the ClO dimer (Cl2O2) formation and therefore may constitute an important intermediate in polar stratospheric ozone loss cycles. Model simulations performed with the Chemical Lagrangian Model of the Stratosphere (CLaMS) will be presented to study the role of radical complexes on polar stratospheric ozone loss processes. The model simulations are performed for the Arctic winter 2002/2003 at a level of 500 K potential temperature and the results are compared to observed ozone loss rates determined by the Match technique. Moreover, recently reported values for the equilibrium constant of the ClO dimer formation are used to restrict the number of possible model results caused by large uncertainties about radical complex chemistry. Our model simulations show that the potential impact of ClO·O2 on polar ozone loss processes is small (dO3/dt≪0.5 ppb/sunlight h) provided that the ClO·O2 complex is only weakly stable. Assuming that the binding energies of the ClOx water complexes are much higher than theoretically predicted an enhancement of the ozone loss rate by up to ≈0.5 ppb/sunlight h is simulated. Because it is unlikely that the ClOx water complexes are much more stable than predicted we conclude that these complexes have no impact on polar stratospheric ozone loss processes. Although large uncertainties about radical complex chemistry exist, our findings show that the potential impact of ClOx radical molecule complexes on polar stratospheric ozone loss processes is very small considering pure gas-phase chemistry. However the existence of ClOx radical-molecule complexes could possibly explain discrepancies for the equilibrium constant of the ClO dimer formation found between recent laboratory and stratospheric measurements.

scholarly journals Model simulations of stratospheric ozone loss caused by enhanced mesospheric NO<sub>x</sub> during Arctic Winter 2003/2004

2008 ◽  
Vol 8 (2) ◽  
pp. 4911-4947
Author(s):  
B. Vogel ◽  
P. Konopka ◽  
J.-U. Grooß ◽  
R. Müller ◽  
B. Funke ◽  
...  
Keyword(s):  
Stratospheric Ozone ◽  
Potential Temperature ◽  
Satellite Observations ◽  
The Arctic ◽  
Local Production ◽  
Model Simulations ◽  
Ozone Loss ◽  
Upper Limit ◽  
Non Local ◽  
The Impact

Abstract. Satellite observations show that the enormous solar proton events (SPEs) in October–November 2003 had significant effects on the composition of the stratosphere and mesosphere in the polar regions. After the October–November 2003 SPEs and in early 2004 significant enhancements of NOx(=NO+NO2) in the upper stratosphere and lower mesosphere in the Northern Hemisphere were observed by several satellite instruments. Here we present global full chemistry calculations performed with the CLaMS model to study the impact of mesospheric NOx intrusions on Arctic polar ozone loss processes in the stratosphere. Several model simulations are preformed with different upper boundary conditions for NOx at 2000 K potential temperature (≈50 km altitude). In our study we focus on the impact of the non-local production of NOx which means the downward transport of enhanced NOx from the mesosphere in the stratosphere. The local production of NOx in the stratosphere is neglected. Our findings show that intrusions of mesospheric air into the stratosphere, transporting high burdens of NOx, affect the composition of the Arctic polar region down to about 400 K (≈17–18 km). We compare our simulated NOx and O3 mixing ratios with satellite observations by ACE-FTS and MIPAS processed at IMK/IAA and derive an upper limit for the ozone loss caused by enhanced mesospheric NOx. Our findings show that in the Arctic polar vortex (Equivalent Lat.>70° N) the accumulated column ozone loss between 350–2000 K potential temperature (≈14–50 km altitude) caused by the SPEs in October–November 2003 in the stratosphere is up to 3.3 DU with an upper limit of 5.5 DU until end of November. Further we found that about 10 DU but lower than 18 DU accumulated ozone loss additionally occurs until end of March 2004 caused by the transport of mesospheric NOx-rich air in early 2004. In the lower stratosphere (350–700 K≈14–27 km altitude) the SPEs of October–November 2003 have negligible small impact on ozone loss processes until end of November and the mesospheric NOx intrusions in early 2004 yield ozone loss about 3.5 DU, but clearly lower than 6.5 DU until end of March. Overall, the non-local production of NOx is an additional variability to the existing variations of the ozone loss observed in the Arctic.

scholarly journals A Match-based approach to the estimation of polar stratospheric ozone loss using Aura Microwave Limb Sounder observations

2015 ◽  
Vol 15 (17) ◽  
pp. 9945-9963 ◽  
Author(s):  
N. J. Livesey ◽  
M. L. Santee ◽  
G. L. Manney
Keyword(s):  
Stratospheric Ozone ◽  
Potential Temperature ◽  
Polar Vortex ◽  
Rate Of Change ◽  
The Arctic ◽  
Air Mass ◽  
Ozone Loss ◽  
Chemical Destruction ◽  
Induced Changes ◽  
The Impact

Abstract. The well-established "Match" approach to quantifying chemical destruction of ozone in the polar lower stratosphere is applied to ozone observations from the Microwave Limb Sounder (MLS) on NASA's Aura spacecraft. Quantification of ozone loss requires distinguishing transport- and chemically induced changes in ozone abundance. This is accomplished in the Match approach by examining cases where trajectories indicate that the same air mass has been observed on multiple occasions. The method was pioneered using ozonesonde observations, for which hundreds of matched ozone observations per winter are typically available. The dense coverage of the MLS measurements, particularly at polar latitudes, allows matches to be made to thousands of observations each day. This study is enabled by recently developed MLS Lagrangian trajectory diagnostic (LTD) support products. Sensitivity studies indicate that the largest influence on the ozone loss estimates are the value of potential vorticity (PV) used to define the edge of the polar vortex (within which matched observations must lie) and the degree to which the PV of an air mass is allowed to vary between matched observations. Applying Match calculations to MLS observations of nitrous oxide, a long-lived tracer whose expected rate of change is negligible on the weekly to monthly timescales considered here, enables quantification of the impact of transport errors on the Match-based ozone loss estimates. Our loss estimates are generally in agreement with previous estimates for selected Arctic winters, though indicating smaller losses than many other studies. Arctic ozone losses are greatest during the 2010/11 winter, as seen in prior studies, with 2.0 ppmv (parts per million by volume) loss estimated at 450 K potential temperature (~ 18 km altitude). As expected, Antarctic winter ozone losses are consistently greater than those for the Arctic, with less interannual variability (e.g., ranging between 2.3 and 3.0 ppmv at 450 K). This study exemplifies the insights into atmospheric processes that can be obtained by applying the Match methodology to a densely sampled observation record such as that from Aura MLS.

scholarly journals Model simulations of stratospheric ozone loss caused by enhanced mesospheric NO<sub>x</sub> during Arctic Winter 2003/2004

2008 ◽  
Vol 8 (17) ◽  
pp. 5279-5293 ◽  
Author(s):  
B. Vogel ◽  
P. Konopka ◽  
J.-U. Grooß ◽  
R. Müller ◽  
B. Funke ◽  
...  
Keyword(s):  
Stratospheric Ozone ◽  
Potential Temperature ◽  
Solar Proton ◽  
Satellite Observations ◽  
The Arctic ◽  
Local Production ◽  
Ozone Loss ◽  
Upper Limit ◽  
Non Local ◽  
The Impact

Abstract. Satellite observations show that the enormous solar proton events (SPEs) in October–November 2003 had significant effects on the composition of the stratosphere and mesosphere in the polar regions. After the October–November 2003 SPEs and in early 2004, significant enhancements of NOx(=NO+NO2) in the upper stratosphere and lower mesosphere in the Northern Hemisphere were observed by several satellite instruments. Here we present global full chemistry calculations performed with the CLaMS model to study the impact of mesospheric NOx intrusions on Arctic polar ozone loss processes in the stratosphere. Several model simulations are preformed with different upper boundary conditions for NOx at 2000 K potential temperature (≈50 km altitude). In our study we focus on the impact of the non-local production of NOx, which means the downward transport of enhanced NOx from the mesosphere to the stratosphere. The local production of NOx in the stratosphere is neglected. Our findings show that intrusions of mesospheric air into the stratosphere, transporting high burdens of NOx, affect the composition of the Arctic polar region down to about 400 K (≈17–18 km). We compare our simulated NOx and O3 mixing ratios with satellite observations by ACE-FTS and MIPAS processed at IMK/IAA and derive an upper limit for the ozone loss caused by enhanced mesospheric NOx. Our findings show that in the Arctic polar vortex (equivalent lat.>70° N) the accumulated column ozone loss between 350–2000 K potential temperature (≈14–50 km altitude) caused by the SPEs in October–November 2003 in the stratosphere is up to 3.3 DU with an upper limit of 5.5 DU until end of November. Further, we found that about 10 DU, but in any case lower than 18 DU, accumulated ozone loss additionally occurred until end of March 2004 caused by the transport of mesospheric NOx-rich air in early 2004. The solar-proton-produced NOx above 55 km due to the SPEs of October–November 2003 had a negligibly small impact on ozone loss processes through the end of November in the lower stratosphere (350–700 K≈14–27 km). The mesospheric NOx intrusions in early 2004 yielded a lower stratospheric ozone loss of about 3.5 DU, and clearly lower than 6.5 DU through the end of March. Overall, the non-local production of NOx is an additional variability in the existing variations of the ozone loss observed in the Arctic.

scholarly journals A Match-based approach to the estimation of polar stratospheric ozone loss using Aura Microwave Limb Sounder observations

2015 ◽  
Vol 15 (7) ◽  
pp. 10041-10083 ◽  
Author(s):  
N. J. Livesey ◽  
M. L. Santee ◽  
G. L. Manney
Keyword(s):  
Stratospheric Ozone ◽  
Potential Temperature ◽  
Polar Vortex ◽  
Rate Of Change ◽  
The Arctic ◽  
Ozone Loss ◽  
Chemically Induced ◽  
Chemical Destruction ◽  
Induced Changes ◽  
The Impact

Abstract. The well-established "Match" approach to quantifying chemical destruction of ozone in the polar lower stratosphere is applied to ozone observations from the Microwave Limb Sounder (MLS) on NASA's Aura spacecraft. Quantification of ozone loss requires distinguishing transport- and chemically induced changes in ozone abundance. This is accomplished in the Match approach by examining cases where trajectories indicate that the same airmass has been observed on multiple occasions. The method was pioneered using ozone sonde observations, for which hundreds of matched ozone observations per winter are typically available. The dense coverage of the MLS measurements, particularly at polar latitudes, allows matches to be made to thousands of observations each day. This study is enabled by recently developed MLS Lagrangian Trajectory Diagnostic (LTD) support products. Sensitivity studies indicate that the largest influence on the ozone loss estimates are the value of potential vorticity (PV) used to define the edge of the polar vortex (within which matched observations must lie) and the degree to which the PV of an airmass is allowed to vary between matched observations. Applying Match calculations to MLS observations of nitrous oxide, a long-lived tracer whose expected rate of change on these timescales is negligible, enables quantification of the impact of transport errors on the Match-based ozone loss estimates. Our loss estimates are generally in agreement with previous estimates for selected Arctic winters, though indicating smaller losses than many other studies. Arctic ozone losses are greatest during the 2010/11 winter, as seen in prior studies, with 2.0 ppmv (parts per million by volume) loss estimated at 450 K potential temperature. As expected, Antarctic winter ozone losses are consistently greater than those for the Arctic, with less interannual variability (e.g., ranging between 2.3 and 3.0 ppmv at 450 K). This study exemplifies the insights into atmospheric processes that can be obtained by applying the Match methodology to a densely sampled observation record such as that from Aura MLS.

Record springtime stratospheric ozone depletion at 80°N in 2020

2021 ◽  
Author(s):  
Ramina Alwarda ◽  
Kristof Bognar ◽  
Kimberly Strong ◽  
Martyn Chipperfield ◽  
Sandip Dhomse ◽  
...  
Keyword(s):  
Ozone Depletion ◽  
Transport Model ◽  
Stratospheric Ozone ◽  
Polar Vortex ◽  
The Arctic ◽  
Optical Absorption Spectroscopy ◽  
Chemical Transport Model ◽  
Polar Stratospheric Clouds ◽  
Ozone Loss ◽  
Stratospheric Clouds

&lt;p&gt;The Arctic winter of 2019-2020 was characterized by an unusually persistent polar vortex and temperatures in the lower stratosphere that were consistently below the threshold for the formation of polar stratospheric clouds (PSCs). These conditions led to ozone loss that is comparable to the Antarctic ozone hole. Ground-based measurements from a suite of instruments at the Polar Environment Atmospheric Research Laboratory (PEARL) in Eureka, Canada (80.05&amp;#176;N, 86.42&amp;#176;W) were used to investigate chemical ozone depletion. The vortex was located above Eureka longer than in any previous year in the 20-year dataset and lidar measurements provided evidence of polar stratospheric clouds (PSCs) above Eureka. Additionally, UV-visible zenith-sky Differential Optical Absorption Spectroscopy (DOAS) measurements showed record ozone loss in the 20-year dataset, evidence of denitrification along with the slowest increase of NO&lt;sub&gt;2&lt;/sub&gt; during spring, as well as enhanced reactive halogen species (OClO and BrO). Complementary measurements of HCl and ClONO&lt;sub&gt;2&lt;/sub&gt; (chlorine reservoir species) from a Fourier transform infrared (FTIR) spectrometer showed unusually low columns that were comparable to 2011, the previous year with significant chemical ozone depletion. Record low values of HNO&lt;sub&gt;3&lt;/sub&gt; in the FTIR dataset are in accordance with the evidence of PSCs and a denitrified atmosphere. Estimates of chemical ozone loss were derived using passive ozone from the SLIMCAT offline chemical transport model to account for dynamical contributions to the stratospheric ozone budget.&lt;/p&gt;

scholarly journals Denitrification, dehydration and ozone loss during the Arctic winter 2015/2016

2017 ◽  
Author(s):  
Farahnaz Khosrawi ◽  
Oliver Kirner ◽  
Björn-Martin Sinnhuber ◽  
Sören Johansson ◽  
Michael Höpfner ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Stratospheric Ozone ◽  
Satellite Observations ◽  
The Arctic ◽  
Cold Pool ◽  
Polar Stratospheric Clouds ◽  
Airborne Measurements ◽  
Ozone Loss ◽  
Polar Stratosphere ◽  
Stratospheric Clouds

Abstract. The Arctic winter 2015/2016 was one of the coldest stratospheric winters in recent years. A stable vortex formed by early December and the early winter was exceptionally cold. Cold pool temperatures dropped below the Nitric Acid Trihydrate (NAT) existence temperature of about 195 K, thus allowing Polar Stratospheric Clouds (PSCs) to form. The low temperatures in the polar stratosphere persisted until early March allowing chlorine activation and catalytic ozone destruction. Satellite observations indicate that sedimentation of PSC particles led to denitrification as well as dehydration of stratospheric layers. Model simulations of the Arctic winter 2015/2016 nudged toward European Center for Medium-Range Weather Forecasts (ECMWF) analyses data were performed with the atmospheric chemistry–climate model ECHAM5/MESSy Atmospheric Chemistry (EMAC) for the Polar Stratosphere in a Changing Climate (POLSTRACC) campaign. POLSTRACC is a High Altitude and LOng Range Research Aircraft (HALO) mission aimed at the investigation of the structure, composition and evolution of the Arctic Upper Troposphere and Lower Stratosphere (UTLS). The chemical and physical processes involved in Arctic stratospheric ozone depletion, transport and mixing processes in the UTLS at high latitudes, polar stratospheric clouds as well as cirrus clouds are investigated. In this study an overview of the chemistry and dynamics of the Arctic winter 2015/2016 as simulated with EMAC is given. Further, chemical-dynamical processes such as denitrification, dehydration and ozone loss during the Arctic winter 2015/2016 are investigated. Comparisons to satellite observations by the Aura Microwave Limb Sounder (Aura/MLS) as well as to airborne measurements with the Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) performed on board of HALO during the POLSTRACC campaign show that the EMAC simulations are in fairly good agreement with observations. We derive a maximum polar stratospheric O3 loss of ~ 2 ppmv or 100 DU in terms of column in mid March. The stratosphere was denitrified by about 8 ppbv HNO3 and dehydrated by about 1 ppmv H2O in mid to end of February. While ozone loss was quite strong, but not as strong as in 2010/2011, denitrification and dehydration were so far the strongest observed in the Arctic stratosphere in the at least past 10 years.

scholarly journals Record-breaking ozone loss in the Arctic winter 2010/2011: comparison with 1996/1997

2012 ◽  
Vol 12 (15) ◽  
pp. 7073-7085 ◽  
Author(s):  
J. Kuttippurath ◽  
S. Godin-Beekmann ◽  
F. Lefèvre ◽  
G. Nikulin ◽  
M. L. Santee ◽  
...  
Keyword(s):  
Transport Model ◽  
Chemical Transport ◽  
The Arctic ◽  
Altitude Range ◽  
Chemical Transport Model ◽  
Model Simulations ◽  
Ozone Loss ◽  
Elevated Ozone ◽  
Record Value ◽  
First Time

Abstract. We present a detailed discussion of the chemical and dynamical processes in the Arctic winters 1996/1997 and 2010/2011 with high resolution chemical transport model (CTM) simulations and space-based observations. In the Arctic winter 2010/2011, the lower stratospheric minimum temperatures were below 195 K for a record period of time, from December to mid-April, and a strong and stable vortex was present during that period. Simulations with the Mimosa-Chim CTM show that the chemical ozone loss started in early January and progressed slowly to 1 ppmv (parts per million by volume) by late February. The loss intensified by early March and reached a record maximum of ~2.4 ppmv in the late March–early April period over a broad altitude range of 450–550 K. This coincides with elevated ozone loss rates of 2–4 ppbv sh−1 (parts per billion by volume/sunlit hour) and a contribution of about 30–55% and 30–35% from the ClO-ClO and ClO-BrO cycles, respectively, in late February and March. In addition, a contribution of 30–50% from the HOx cycle is also estimated in April. We also estimate a loss of about 0.7–1.2 ppmv contributed (75%) by the NOx cycle at 550–700 K. The ozone loss estimated in the partial column range of 350–550 K exhibits a record value of ~148 DU (Dobson Unit). This is the largest ozone loss ever estimated in the Arctic and is consistent with the remarkable chlorine activation and strong denitrification (40–50%) during the winter, as the modeled ClO shows ~1.8 ppbv in early January and ~1 ppbv in March at 450–550 K. These model results are in excellent agreement with those found from the Aura Microwave Limb Sounder observations. Our analyses also show that the ozone loss in 2010/2011 is close to that found in some Antarctic winters, for the first time in the observed history. Though the winter 1996/1997 was also very cold in March–April, the temperatures were higher in December–February, and, therefore, chlorine activation was moderate and ozone loss was average with about 1.2 ppmv at 475–550 K or 42 DU at 350–550 K, as diagnosed from the model simulations and measurements.

scholarly journals Simulation of denitrification and ozone loss for the Arctic winter 2002/2003

2005 ◽  
Vol 5 (6) ◽  
pp. 1437-1448 ◽  
Author(s):  
J.-U. Grooß ◽  
G. Günther ◽  
R. Müller ◽  
P. Konopka ◽  
S. Bausch ◽  
...  
Keyword(s):  
Inorganic Nitrogen ◽  
Potential Temperature ◽  
Three Dimensional ◽  
Lagrangian Model ◽  
The Arctic ◽  
Particle Nucleation ◽  
Ozone Loss ◽  
Dimensional Version ◽  
Total Inorganic Nitrogen ◽  
Catalytic Cycles

Abstract. We present simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) for the Arctic winter 2002/2003. We integrated a Lagrangian denitrification scheme into the three-dimensional version of CLaMS that calculates the growth and sedimentation of nitric acid trihydrate (NAT) particles along individual particle trajectories. From those, we derive the HNO3 downward flux resulting from different particle nucleation assumptions. The simulation results show a clear vertical redistribution of total inorganic nitrogen ( ), with a maximum vortex average permanent removal of over 5ppb in late December between 500 and 550K and a corresponding increase of of over 2ppb below about 450K. The simulated vertical redistribution of is compared with balloon observations by MkIV and in-situ observations from the high altitude aircraft Geophysica. Assuming a globally uniform NAT particle nucleation rate of 7.8x10-6cm-3h-1 in the model, the observed denitrification is well reproduced. In the investigated winter 2002/2003, the denitrification has only moderate impact (≤14%) on the simulated vortex average ozone loss of about 1.1ppm near the 460K level. At higher altitudes, above 600K potential temperature, the simulations show significant ozone depletion through -catalytic cycles due to the unusual early exposure of vortex air to sunlight.

The Influence of Ozone Feedbacks on Surface Climate following Spring Arctic Ozone Depletion

2021 ◽  
Author(s):  
Marina Friedel ◽  
Gabriel Chiodo ◽  
Andrea Stenke ◽  
Daniela Domeisen ◽  
Stefan Muthers ◽  
...  
Keyword(s):  
Ozone Depletion ◽  
Arctic Oscillation ◽  
Stratospheric Ozone ◽  
The Arctic ◽  
Model Simulations ◽  
Temperature Anomalies ◽  
Surface Climate ◽  
Anomalous Surface ◽  
Surface Weather ◽  
Surface Patterns

&lt;p&gt;Links between springtime Arctic stratospheric ozone anomalies and anomalous surface weather in the Northern Hemisphere have been found recently. Stratospheric ozone thus provides valuable information which may help to improve seasonal predictability. However, the extent and causality of the ozone-surface climate coupling remain unclear and many state-of-the-art forecast models lack any representation of ozone feedbacks on planetary circulation.&lt;/p&gt;&lt;p&gt;We investigate the importance of the ozone-surface climate coupling with two Chemistry Climate Models, contrasting simulations with fully interactive ozone against prescribed zonally averaged climatological ozone under fixed present-day boundary conditions. We focus on springtime Arctic ozone minima and compare subsequent surface patterns in runs with and without interactive ozone, thus rendering a detailed and physically-based quantification of the stratospheric ozone impact on surface climate possible. &amp;#160;&lt;/p&gt;&lt;p&gt;All model simulations show a connection between Arctic ozone minima and a positive phase of the Arctic Oscillation in the month after the depletion in spring. Runs with interactive ozone chemistry show an amplified surface response and a 40% stronger Arctic Oscillation index after ozone depletion. This amplified Arctic Oscillation goes along with enhanced positive surface temperature anomalies over Eurasia. Moreover, composite surface patterns after spring ozone minima in model simulations with interactive ozone show a better agreement with composites in reanalysis data compared to runs with prescribed ozone.&lt;/p&gt;&lt;p&gt;Mechanisms whereby stratospheric ozone affects both the stratospheric and tropospheric circulation are explored. These include the reduction of short-wave heating over the pole due to ozone loss, thus amplifying stratospheric temperature anomalies and allowing for an intensification of the polar vortex with subsequent impacts on wave propagation and the stratospheric meridional circulation. This suggests that ozone is not only passively responding to stratospheric dynamics, but actively feeds back into the circulation. Following these results, stratospheric ozone anomalies actively contribute to anomalous surface weather in spring, emphasizing the potential importance of interactive ozone chemistry for seasonal predictions.&lt;/p&gt;

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