scholarly journals Arctic Oscillation response to the 1991 Mount Pinatubo eruption: Effects of volcanic aerosols and ozone depletion

2002 ◽  
Vol 107 (D24) ◽  
Author(s):  
Georgiy Stenchikov
Keyword(s):  
Ozone Depletion ◽  
Arctic Oscillation ◽  
Mount Pinatubo ◽  
Pinatubo Eruption ◽  
Volcanic Aerosols

scholarly journals Scant evidence for a volcanically forced winter warming over Eurasia following the Krakatau eruption of August 1883

2020 ◽  
Vol 20 (22) ◽  
pp. 13687-13700
Author(s):  
Lorenzo M. Polvani ◽  
Suzana J. Camargo
Keyword(s):  
Coupled Model ◽  
Large Magnitude ◽  
Low Latitude ◽  
Surface Warming ◽  
Winter Warming ◽  
Pinatubo Eruption ◽  
Intercomparison Project ◽  
Volcanic Aerosols ◽  
Instrumental Period ◽  
New Evidence

Abstract. A recent study has presented compelling new evidence suggesting that the observed Eurasian warming in the winter following the 1992 Pinatubo eruption was, in all likelihood, unrelated to the presence of volcanic aerosols in the stratosphere. Building on that study, we turn our attention to the only other low-latitude eruption in the instrumental period with a comparably large magnitude: the Krakatau eruption of August 1883. We study the temperature anomalies in the first winter following that eruption in detail, analyzing (1) observations, (2) reanalyses, and (3) models. Three findings emerge from our analysis. First, the observed post-Krakatau winter warming over Eurasia was unremarkable (only between 1σ and 2σ of the distribution from 1850 to present). Second, reanalyses based on assimilating surface pressure alone indicate the existence of very large uncertainties, so much so that a Eurasian cooling is not incompatible with those reanalyses. Third, models robustly show the complete absence of a volcanically forced Eurasian winter warming: here, we analyze both a 100-member initial-condition ensemble and 140 simulations from Phase 5 of the Coupled Model Intercomparison Project. This wealth of evidence strongly suggests that, as in the case of Pinatubo, the observed warming over Eurasia in the winter of 1883–84 was, in all likelihood, unrelated to the Krakatau eruption. This, taken together with a similar result for Pinatubo, leads us to conclude that if volcanically forced Eurasian winter warming exists at all, an eruption with a magnitude far exceeding these two events would be needed to produce a detectable surface warming.

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

<p>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.</p><p>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.  </p><p>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.</p><p>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.</p>

Mount Pinatubo Aerosols, Chlorofluorocarbons, and Ozone Depletion

Science ◽  
1992 ◽  
Vol 257 (5074) ◽  
pp. 1239-1242 ◽  
Author(s):  
G. Brasseur ◽  
C. Granier
Keyword(s):  
Ozone Depletion ◽  
Mount Pinatubo

Long-term observations of the midlatitude stratospheric aerosol from the Mount Pinatubo eruption

1996 ◽  
Author(s):  
David C. Woods ◽  
David M. Winker ◽  
Otto Youngbluth, Jr. ◽  
Mary T. Osborn ◽  
Robert J. DeCoursey
Keyword(s):  
Stratospheric Aerosol ◽  
Mount Pinatubo ◽  
Pinatubo Eruption

scholarly journals Can we explain the observed methane variability after the Mount Pinatubo eruption?

2015 ◽  
Vol 15 (13) ◽  
pp. 19111-19160
Author(s):  
N. Bândă ◽  
M. Krol ◽  
M. van Weele ◽  
T. van Noije ◽  
P. Le Sager ◽  
...  
Keyword(s):  
Growth Rate ◽  
Biomass Burning ◽  
Partial Recovery ◽  
Mount Pinatubo ◽  
Sources And Sinks ◽  
Time Period ◽  
Pinatubo Eruption ◽  
Emission Changes

Abstract. The CH4 growth rate in the atmosphere showed large variations after the Pinatubo eruption in June 1991. A decrease of more than 10 ppb yr-1 in the growth rate over the course of 1992 was reported and a partial recovery in the following year. Although several reasons have been proposed to explain the evolution of CH4 after the eruption, their contributions to the observed variations are not yet resolved. CH4 is removed from the atmosphere by the reaction with tropospheric OH, which in turn is produced by O3 photolysis under UV radiation. The CH4 removal after the Pinatubo eruption might have been affected by changes in tropospheric UV levels due to the presence of stratospheric SO2 and sulfate aerosols, and due to enhanced ozone depletion on Pinatubo aerosols. The perturbed climate after the eruption also altered both sources and sinks of atmospheric CH4. Furthermore, CH4 concentrations were influenced by other factors of natural variability in that period, such as ENSO and biomass burning events. Emissions of CO, NOX and NMVOCs also affected CH4 concentrations indirectly by influencing tropospheric OH levels. Potential drivers of CH4 variability are investigated using the TM5 global chemistry model. The contribution that each driver had to the global CH4 variability during the period 1990 to 1995 is quantified. We find that a decrease of 8–10 ppb yr-1 CH4 is explained by a combination of the above processes. However, the timing of the minimum growth rate is found 6–9 months later than observed. The long-term decrease in CH4 growth rate over the period 1990 to 1995 is well captured and can be attributed to an increase in OH concentrations over this time period. Potential uncertainties in our modelled CH4 growth rate include emissions of CH4 from wetlands, biomass burning emissions of CH4 and other compounds, biogenic NMVOC and the sensitivity of OH to NMVOC emission changes. Two inventories are used for CH4 emissions from wetlands, ORCHIDEE and LPJ, to investigate the role of uncertainties in these emissions. Although the higher climate sensitivity of ORCHIDEE improves the simulated CH4 growth rate change after Pinatubo, none of the two inventories properly captures the observed CH4 variability in this period.

Reconciling the BDC response in climate models to the volcanic forcings with reanalyses

2020 ◽  
Author(s):  
Mohamadou Diallo ◽  
Hella Garny ◽  
Roland Eichinger ◽  
Valentina Aquila ◽  
Manfred Ern ◽  
...  
Keyword(s):  
Climate Models ◽  
Climate Model ◽  
Model Simulations ◽  
Current Climate ◽  
Climate Simulations ◽  
Pinatubo Eruption ◽  
Speed Up ◽  
Stratospheric Circulation ◽  
Volcanic Aerosols ◽  
Climate Model Simulations

<p>The stratospheric Brewer--Dobson circulation (BDC) is an important element of climate system as it determines the concentration of radiatively active trace gases like water vapor, ozone and aerosol above the tropopause. Climate models predict that increasing greenhouse gas levels speed up the stratospheric circulation. BDC changes is substantially modulated by different modes of climate variability (QBO, ENSO, solar cycle), including the volcanic aerosols. However, such variability is often not reliably included or represented in current climate model simulations, challenging the evaluation of models’ behavior against observations and constituting a major uncertainty in current climate simulations. </p><p>Here, we investigate the main differences between the reanalysis and the CCMI/CMIP6 climate models’ response to stratospheric volcanic forcings regarding the depth/strength of the stratospheric BDC, with a focus on potential changes in the deep and shallow circulation branches. We also discuss the key reasons of the discrepancies (incl. uncertainties associated with volcanological forcing datasets and missing direct aerosol heating in the reanalysis) in the BDC response between reanalysis-driven and climate model simulations in the lower, mid and upper stratosphere. Finally, we assess the dynamical mechanisms involved in the volcanically-induced BDC changes to understand the opposite regime between lower, middle and upper stratosphere after the Mt Pinatubo eruption.</p>

Aerosols as dynamical tracers in the lower stratosphere: Ozone versus aerosol correlation after the Mount Pinatubo eruption

1995 ◽  
Vol 100 (D6) ◽  
pp. 11147 ◽  
Author(s):  
S. Borrmann ◽  
J. E. Dye ◽  
D. Baumgardner ◽  
M. H. Proffitt ◽  
J. J. Margitan ◽  
...  
Keyword(s):  
Lower Stratosphere ◽  
Mount Pinatubo ◽  
Pinatubo Eruption

Radiative Climate Forcing by the Mount Pinatubo Eruption

Science ◽  
1993 ◽  
Vol 259 (5100) ◽  
pp. 1411-1415 ◽  
Author(s):  
P. Minnis ◽  
E. F. Harrison ◽  
L. L. Stowe ◽  
G. G. Gibson ◽  
F. M. Denn ◽  
...  
Keyword(s):  
Climate Forcing ◽  
Mount Pinatubo ◽  
Pinatubo Eruption
Sign in / Sign up

Export Citation Format

Share Document