In situ measurements of stratospheric ozone depletion rates in the Arctic winter 1991/1992: A Lagrangian approach

Stratospheric ozone depletion in the Antarctic is well known to cause changes in Southern Hemisphere tropospheric climate; however, because of its smaller magnitude in the Arctic, the effects of stratospheric ozone depletion on Northern Hemisphere tropospheric climate are not as obvious or well understood. Recent research using both global climate models and observational data has determined that the impact of ozone depletion on ozone extremes can affect interannual variability in tropospheric circulation in the Northern Hemisphere in spring. To further this work, we use a coupled chemistry&#8211;climate model to examine the difference in high cloud between years with anomalously low and high Arctic stratospheric ozone concentrations. We find that low ozone extremes during the late twentieth century, when ozone-depleting substances (ODS) emissions are higher, are related to a decrease in upper tropospheric stability and an increase in high cloud fraction, which may contribute to enhanced Arctic surface warming in spring through a positive longwave cloud radiative effect. A better understanding of how Arctic climate is affected by ODS emissions, ozone depletion, and ozone extremes will lead to improved predictions of Arctic climate and its associated feedbacks with atmospheric fields as ozone levels recover.

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Shedding new light on the radiative impacts of ozone-depleting substances

10.5194/egusphere-egu2020-4687 ◽

2020 ◽

Author(s):

Gabriel Chiodo ◽

Lorenzo M. Polvani

Keyword(s):

Twentieth Century ◽

Ozone Depletion ◽

Stratospheric Ozone ◽

Walker Circulation ◽

Climate Impacts ◽

The Arctic ◽

Temperature Structure ◽

Stratospheric Ozone Depletion ◽

Ozone Depleting Substances ◽

The Walker Circulation

It is well established that ozone-depleting substances (ODS) have been the primary cause of stratospheric ozone depletion. It is also widely accepted that stratospheric ozone depletion has been the primary driver of summertime circulation trends in the Austral Hemisphere in the second half of the twentieth century. However, the climate impacts of ODS that are independent of ozone depletion have received little attention. It has long been known that, while much less abundant than carbon dioxide, ODS have a much higher global warming potential (GWP) ecent studies have indicated that ODS may have played a key-role in the observed weakening trends of the Walker circulation (Polvani and Bellomo, 2019), and in the warming of the Arctic and the associated sea ice loss (Polvani et al., 2020). that the climate efficacy of ODS may be much larger than previously thought, but .Here, we seek to better understand the radiative effect of ODS in the global atmosphere. Instead of confining our attention on a single metric, e.g. globally averaged radiative forcing (RF) or GWP which are typically reported in the IPCC Assessment Reports, we seek to understand how ODS alter the temperature structure of the entire atmosphere. Focusing on the half-century 1950-2000, which saw the largest growth of ODS concentrations in the atmosphere, we start by performing careful computations of the RF of individual ODS, including the effects of rapid temperature adjustments. We then explore how the vertical and latitudinal distribution of ODS (which are not well mixed in the stratosphere) affects their RF, and what temperature responses are associated with those changes. These calculations are repeated individually for each of the other well-mixed GHG, as well as for other composition changes arising from ODS (ozone depletion). It is shown that ODS, in contrast to other GHG, warm the lower stratosphere, implying a different fingerprint from CO2. Furthermore, the RF of ODS exhibits the largest meridional gradient of any other well-mixed GHG. Implications for the climate efficacy of ODS, and more generally for climate sensitivity, will be discussed.ReferencesPolvani, L.M and K. Bellomo: The key role of ozone depleting substances in weakening the Walker circulation in the second half of the 20th century, J. Climate, 32, 1411-1418 (2019).Polvani et al.,: Substantial twentieth-century Arctic warmng caused by ozone depleting substances, Nature Climate Change, in press (2019)

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Impacts of Stratospheric Ozone Extremes on Arctic High Cloud

Journal of Climate ◽

10.1175/jcli-d-19-0867.1 ◽

2020 ◽

Vol 33 (20) ◽

pp. 8869-8884

Author(s):

Sarah Maleska ◽

Karen L. Smith ◽

John Virgin

Keyword(s):

Northern Hemisphere ◽

Ozone Depletion ◽

Climate Model ◽

Stratospheric Ozone ◽

Global Climate Models ◽

Arctic Climate ◽

The Arctic ◽

Stratospheric Ozone Depletion ◽

High Cloud ◽

The Impact

AbstractStratospheric ozone depletion in the Antarctic is well known to cause changes in Southern Hemisphere tropospheric climate; however, because of its smaller magnitude in the Arctic, the effects of stratospheric ozone depletion on Northern Hemisphere tropospheric climate are not as obvious or well understood. Recent research using both global climate models and observational data has determined that the impact of ozone depletion on ozone extremes can affect interannual variability in tropospheric circulation in the Northern Hemisphere in spring. To further this work, we use a coupled chemistry–climate model to examine the difference in high cloud between years with anomalously low and high Arctic stratospheric ozone concentrations. We find that low ozone extremes during the late twentieth century, when ozone-depleting substances (ODS) emissions are higher, are related to a decrease in upper tropospheric stability and an increase in high cloud fraction, which may contribute to enhanced Arctic surface warming in spring through a positive longwave cloud radiative effect. A better understanding of how Arctic climate is affected by ODS emissions, ozone depletion, and ozone extremes will lead to improved predictions of Arctic climate and its associated feedbacks with atmospheric fields as ozone levels recover.

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Impacts of stratospheric ozone extremes on Arctic high cloud

10.5194/egusphere-egu2020-9282 ◽

2020 ◽

Author(s):

Karen Smith ◽

Sarah Maleska ◽

John Virgin

Keyword(s):

Northern Hemisphere ◽

Ozone Depletion ◽

Climate Model ◽

Stratospheric Ozone ◽

Global Climate Models ◽

Arctic Climate ◽

The Arctic ◽

Stratospheric Ozone Depletion ◽

High Cloud ◽

The Impact

Stratospheric ozone depletion in the Antarctic is well known to cause changes in Southern Hemisphere tropospheric climate; however, due to its smaller magnitude in the Arctic, the effects of stratospheric ozone depletion on Northern Hemisphere tropospheric climate are not as obvious or well understood. Recent research using both global climate models and observational data has determined that the impact of ozone depletion on ozone extremes can affect interannual variability in tropospheric circulation in the Northern Hemisphere in spring. To further this work, we use a coupled chemistry-climate model to examine the difference in high cloud between years with anomalously low and high Arctic stratospheric ozone concentrations. We find that low ozone extremes during the late twentieth century, when ODS emissions are higher, are related to a decrease in upper tropospheric stability and an increase in high cloud fraction, which may have contributed to Arctic surface warming via a positive longwave cloud radiative effect in the past few decades compared to other regions. A better understanding of how Arctic climate is affected by ODS emissions, ozone depletion and ozone extremes will lead to improved predictions of Arctic climate and its associated feedbacks with atmospheric fields as ozone levels recover.

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The Geography of Malignant Melanoma in the Nordic Countries: The Implications of Stratospheric Ozone Depletion

Geografiska Annaler Series B Human Geography ◽

10.2307/490595 ◽

1994 ◽

Vol 76 (2) ◽

pp. 129 ◽

Cited By ~ 2

Author(s):

Asbjorn Aase ◽

Graham Bentham

Keyword(s):

Malignant Melanoma ◽

Ozone Depletion ◽

Stratospheric Ozone ◽

Nordic Countries ◽

Stratospheric Ozone Depletion

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In situ measurements constraining the role of sulphate aerosols in mid-latitude ozone depletion

Nature ◽

10.1038/363509a0 ◽

1993 ◽

Vol 363 (6429) ◽

pp. 509-514 ◽

Cited By ~ 212

Author(s):

D. W. Fahey ◽

S. R. Kawa ◽

E. L. Woodbridge ◽

P. Tin ◽

J. C. Wilson ◽

...

Keyword(s):

Ozone Depletion ◽

In Situ Measurements ◽

Sulphate Aerosols

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ChemInform Abstract: Towards a Laboratory Strategy for the Study of Heterogeneous Catalysis in Stratospheric Ozone Depletion

ChemInform ◽

10.1002/chin.199445273 ◽

2010 ◽

Vol 25 (45) ◽

pp. no-no

Author(s):

M. R. S. MCCOUSTRA ◽

A. B. HORN

Keyword(s):

Heterogeneous Catalysis ◽

Ozone Depletion ◽

Stratospheric Ozone ◽

Stratospheric Ozone Depletion

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Record springtime stratospheric ozone depletion at 80°N in 2020

10.5194/egusphere-egu21-8892 ◽

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

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&#176;N, 86.42&#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 NO2 during spring, as well as enhanced reactive halogen species (OClO and BrO). Complementary measurements of HCl and ClONO2 (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 HNO3 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.

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