Impact of solar‐induced stratospheric ozone decline on Southern Hemisphere westerlies during the Late Maunder Minimum

Abstract. Chemistry climate models are important tools for addressing interactions of composition and climate in the Earth System. In particular, they are used for assessing the combined roles of greenhouse gases and ozone in Southern Hemisphere climate and weather. Here we present an evaluation of the Australian Community Climate and Earth System Simulator-Chemistry Climate Model, focusing on the Southern Hemisphere and the Australian region. This model is used for the Australian contribution to the international Chemistry-Climate Model Initiative, which is soliciting hindcast, future projection and sensitivity simulations. The model simulates global total column ozone (TCO) distributions accurately, with a slight delay in the onset and recovery of springtime Antarctic ozone depletion, and consistently higher ozone values. However, October averaged Antarctic TCO from 1960 to 2010 show a similar amount of depletion compared to observations. A significant innovation is the evaluation of simulated vertical profiles of ozone and temperature with ozonesonde data from Australia, New Zealand and Antarctica from 38 to 90° S. Excess ozone concentrations (up to 26.4 % at Davis during winter) and stratospheric cold biases (up to 10.1 K at the South Pole) outside the period of perturbed springtime ozone depletion are seen during all seasons compared to ozonesondes. A disparity in the vertical location of ozone depletion is seen: centered around 100 hPa in ozonesonde data compared to above 50 hPa in the model. Analysis of vertical chlorine monoxide profiles indicates that colder Antarctic stratospheric temperatures (possibly due to reduced mid-latitude heat flux) are artificially enhancing polar stratospheric cloud formation at high altitudes. The models inability to explicitly simulated supercooled ternary solution may also explain the lack of depletion at lower altitudes. The simulated Southern Annular Mode (SAM) index compares well with ERA-Interim data. Accompanying these modulations of the SAM, 50 hPa zonal wind differences between 2001–2010 and 1979–1998 show increasing zonal wind strength southward of 60° S during December for both the model simulations and ERA-Interim data. These model diagnostics shows that the model reasonably captures the stratospheric ozone driven chemistry-climate interactions important for Australian climate and weather while highlighting areas for future model development.

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The control of the Southern Hemisphere Westerlies on the position of the Subtropical Front

Journal of Geophysical Research Oceans ◽

10.1002/jgrc.20407 ◽

2013 ◽

Vol 118 (10) ◽

pp. 5669-5675 ◽

Cited By ~ 28

Author(s):

Agatha M. De Boer ◽

Robert M. Graham ◽

Matthew D. Thomas ◽

Karen E. Kohfeld

Keyword(s):

Southern Hemisphere ◽

Subtropical Front ◽

Southern Hemisphere Westerlies

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Euro-Atlantic Atmospheric Circulation during the Late Maunder Minimum

Journal of Climate ◽

10.1175/jcli-d-17-0261.1 ◽

2018 ◽

Vol 31 (10) ◽

pp. 3849-3863 ◽

Cited By ~ 9

Author(s):

Javier Mellado-Cano ◽

David Barriopedro ◽

Ricardo García-Herrera ◽

Ricardo M. Trigo ◽

Mari Carmen Álvarez-Castro

Keyword(s):

Atmospheric Circulation ◽

North Atlantic ◽

Decadal Variability ◽

Complete Classification ◽

Maunder Minimum ◽

The North ◽

Late Maunder Minimum ◽

The North Atlantic Oscillation ◽

Nao Pattern

Abstract This paper presents observational evidence of the atmospheric circulation during the Late Maunder Minimum (LMM, 1685–1715) based on daily wind direction observations from ships in the English Channel. Four wind directional indices and 8-point wind roses are derived at monthly scales to characterize the LMM. The results indicate that the LMM was characterized by a pronounced meridional circulation and a marked reduction in the frequency of westerly days all year round, as compared to the present (1981–2010). The winter circulation contributed the most to the cold conditions. Nevertheless, findings indicate that the LMM in Europe was more heterogeneous than previously thought, displaying contrasting spatial patterns in both circulation and temperature, as well as large decadal variability. In particular, there was an increase of northerly winds favoring colder winters in the first half of the LMM, but enhanced southerlies contributing to milder conditions in the second half of the LMM. The analysis of the atmospheric circulation yields a new and complete classification of LMM winters. The temperature inferred from the atmospheric circulation confirms the majority of extremely cold winters well documented in the literature, while uncovering other less documented cold and mild winters. The results also suggest a nonstationarity of the North Atlantic Oscillation (NAO) pattern within the LMM, with extremely cold winters being driven by negative phases of a “high zonal” NAO pattern and “low zonal” NAO patterns dominating during moderately cold winters.

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Examination of the 2002 major warming in the southern hemisphere using ground-based and Odin/SMR assimilated data: stratospheric ozone distributions and tropic/mid-latitude exchange

Canadian Journal of Physics ◽

10.1139/p07-143 ◽

2007 ◽

Vol 85 (11) ◽

pp. 1287-1300 ◽

Cited By ~ 30

Author(s):

H Bencherif ◽

L El Amraoui ◽

N Semane ◽

S Massart ◽

D Vidyaranya Charyulu ◽

...

Keyword(s):

Nitrous Oxide ◽

Southern Hemisphere ◽

Transport Model ◽

Stratospheric Ozone ◽

Three Dimensional ◽

Polar Vortex ◽

Low Latitude ◽

Height Range ◽

Weather Forecasts ◽

European Centre

Following an exceptionally active winter, the 2002 Southern Hemisphere (SH) major warming occurred in late September. It was preceded by three minor warming events that occurred in late August and early September, and yielded vortex split and break-down over Antarctica. Ozone (O3 and nitrous oxide (N2O) profiles obtained during that period of time (15 August – 4 October) by the Sub-Millimetre Radiometer (SMR) aboard the Odin satellite are assimilated into MOCAGE (Modélisation Isentrope du transport Mésoéchelle de l'Ozone Stratosphérique par Advection), a global three-dimensional chemistry transport model of Météo-France. The assimilated algorithm is a three-dimensional-FGAT built by the European Centre for Research and Advance Training in Scientific Computation (CERFACS) using the PALM (Projet d'Assimilation par Logiciel Multi-méthode) software. The assimilated O3 and N2O profiles and isentropic distributions are compared to ground-based measurements (LIDAR and balloon-sonde) and to maps of advected potential vorticity (APV). The latter is computed by the MIMOSA (Modélisation Isentrope du transport Mésoéchelle de l'Ozone Stratosphérique par Advection) model, a high-resolution advection transport model, using meteorological fields from the European Centre for Medium-Range Weather Forecasts (ECMWF). It is found that O3 concentrations retrieved by the MOCAGE–PALM assimilation system show a reasonably good agreement in the 20–28 km height range when compared with ground-based profiles. This altitude range corresponds to the intersection between the MOCAGE levels (0–28 km) and SMR O3 retrievals (20–50 km). Moreover, comparison of N2O assimilated fields with MIMOSA APV maps indicates that the dramatic split and subsequent break-down of the polar vortex, as well as the associated mixing of mid- and low-latitude stratospheric air, are well resolved and pictured by MOCAGE–PALM. The present study demonstrates also that the tremendous dynamics and associated polar vortex deformations during the 2002-austral-winter have modified ozone and nitrous oxide distributions not only at the vicinity of the polar vortex, but over topics and subtropics as well. PACS Nos.: 92.60.H–, 92.60.Hd, 92.70.Cp, 92.70.Gt

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Effects on stratospheric ozone and temperature during the Maunder Minimum

Geophysical Research Letters ◽

10.1029/98gl00057 ◽

1998 ◽

Vol 25 (4) ◽

pp. 523-526 ◽

Cited By ~ 15

Author(s):

Donald J. Wuebbles ◽

Chu-Feng Wei ◽

Kenneth O. Patten

Keyword(s):

Stratospheric Ozone ◽

Maunder Minimum

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Technical note: LIMS observations of lower stratospheric ozone in the southern polar springtime of 1978

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-3663-2020 ◽

2020 ◽

Vol 20 (6) ◽

pp. 3663-3668

Author(s):

Ellis Remsberg ◽

V. Lynn Harvey ◽

Arlin Krueger ◽

Larry Gordley ◽

John C. Gille ◽

...

Keyword(s):

Nitric Acid ◽

Nitrogen Dioxide ◽

Southern Hemisphere ◽

Polar Region ◽

Lower Stratosphere ◽

Stratospheric Ozone ◽

Polar Vortex ◽

Technical Note ◽

Stratospheric Ozone Layer ◽

Antarctic Ozone

Abstract. The Nimbus 7 Limb Infrared Monitor of the Stratosphere (LIMS) instrument operated from 25 October 1978 through 28 May 1979. This note focuses on its Version 6 (V6) data and indications of ozone loss in the lower stratosphere of the Southern Hemisphere subpolar region during the last week of October 1978. We provide profiles and maps that show V6 ozone values of only 2 to 3 ppmv at 46 hPa within the edge of the polar vortex near 60∘ S from late October through mid-November 1978. There are also low values of V6 nitric acid (∼3 to 6 ppbv) and nitrogen dioxide (< 1 ppbv) at the same locations, indicating that conditions were suitable for a chemical loss of Antarctic ozone some weeks earlier. These “first light” LIMS observations provide the earliest space-based view of conditions within the lower stratospheric ozone layer of the southern polar region in springtime.

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Hydrographic changes in the Agulhas Recirculation Region during the late Quaternary

Climate of the Past ◽

10.5194/cp-10-745-2014 ◽

2014 ◽

Vol 10 (2) ◽

pp. 745-758

Author(s):

D. K. Naik ◽

R. Saraswat ◽

N. Khare ◽

A. C. Pandey ◽

R. Nigam

Keyword(s):

Indian Ocean ◽

Southern Hemisphere ◽

Recirculation Region ◽

Glacial Period ◽

Last Glacial Period ◽

Subtropical Front ◽

Last Glacial ◽

Southwestern Indian Ocean ◽

Southern Hemisphere Westerlies ◽

The Last Glacial

Abstract. The strength of Southern Hemisphere westerlies, as well as the positions of the subtropical front (STF), Agulhas Current (AC) and Agulhas Return Current (ARC) control the hydrography of the southwestern Indian Ocean. Although equatorward migration of the STF and reduction in Agulhas leakage were reported during the last glacial period, the fate of ARC during the last glacial–interglacial cycle is not clear. Therefore, in order to understand changes in the position and strength of ARC during the last glacial–interglacial cycle, here we reconstruct hydrographic changes in the southwestern Indian Ocean from temporal variation in planktic foraminiferal abundance, stable isotopic ratio (δ18O) and trace elemental ratio (Mg/Ca) of planktic foraminifera Globigerina bulloides in a core collected from the Agulhas Recirculation Region (ARR) in the southwestern Indian Ocean. Increased abundance of G. bulloides suggests that the productivity in the southwestern Indian Ocean increased during the last glacial period which confirms previous reports of high glacial productivity in the Southern Ocean. The increased productivity was likely driven by the intensified Southern Hemisphere westerlies supported by an equatorward migration of the subtropical front. Increase in relative abundance of Neogloboquadrina incompta suggests seasonally strong thermocline and enhanced advection of southern source water in the southwestern Indian Ocean as a result of strengthened ARC, right through MIS 4 to MIS 2, during the last glacial period. Therefore, it is inferred that over the last glacial–interglacial cycle, the hydrography of the southwestern Indian Ocean was driven by strengthened westerlies, ARC as well as a migrating subtropical front.

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