TY - JOUR

T1 - Northern hemispheric winter warming pattern after tropical volcanic eruptions

T2 - Sensitivity to the ozone climatology

AU - Muthers, S.

AU - Anet, J. G.

AU - Raible, C. C.

AU - Broennimann, S.

AU - Rozanov, E.

AU - Arfeuille, F.

AU - Peter, T.

AU - Beer, J.

AU - Steinhilber, F.

AU - Brugnara, Y.

AU - Schmutz, W.

PY - 2014/2/16

Y1 - 2014/2/16

N2 - An important key for the understanding of the dynamic response to large tropical volcanic eruptions is the warming of the tropical lower stratosphere and the concomitant intensification of the polar vortices. Although this mechanism is reproduced by most general circulation models today, most models still fail in producing an appropriate winter warming pattern in the Northern Hemisphere. In this study ensemble sensitivity experiments were carried out with a coupled atmosphere-ocean model to assess the influence of different ozone climatologies on the atmospheric dynamics and in particular on the northern hemispheric winter warming. The ensemble experiments were perturbed by a single Tambora-like eruption. Larger meridional gradients in the lower stratospheric ozone favor the coupling of zonal wind anomalies between the stratosphere and the troposphere after the eruption. The associated sea level pressure, temperature, and precipitation patterns are more pronounced and the northern hemispheric winter warming is highly significant. Conversely, weaker meridional ozone gradients lead to a weaker response of the winter warming and the associated patterns. The differences in the number of stratosphere-troposphere coupling events between the ensembles experiments indicate a nonlinear response behavior of the dynamics with respect to the ozone and the volcanic forcing.

AB - An important key for the understanding of the dynamic response to large tropical volcanic eruptions is the warming of the tropical lower stratosphere and the concomitant intensification of the polar vortices. Although this mechanism is reproduced by most general circulation models today, most models still fail in producing an appropriate winter warming pattern in the Northern Hemisphere. In this study ensemble sensitivity experiments were carried out with a coupled atmosphere-ocean model to assess the influence of different ozone climatologies on the atmospheric dynamics and in particular on the northern hemispheric winter warming. The ensemble experiments were perturbed by a single Tambora-like eruption. Larger meridional gradients in the lower stratospheric ozone favor the coupling of zonal wind anomalies between the stratosphere and the troposphere after the eruption. The associated sea level pressure, temperature, and precipitation patterns are more pronounced and the northern hemispheric winter warming is highly significant. Conversely, weaker meridional ozone gradients lead to a weaker response of the winter warming and the associated patterns. The differences in the number of stratosphere-troposphere coupling events between the ensembles experiments indicate a nonlinear response behavior of the dynamics with respect to the ozone and the volcanic forcing.

KW - volcanic eruptions

KW - ozone

KW - climate modeling

KW - dynamics

KW - winter warming pattern

KW - stratosphere-troposphere coupling

KW - ARCTIC OSCILLATION RESPONSE

KW - QUASI-BIENNIAL OSCILLATION

KW - PINATUBO ERUPTION

KW - SOUTHERN-HEMISPHERE

KW - STRATOSPHERIC CIRCULATION

KW - ATLANTIC OSCILLATION

KW - DOWNWARD PROPAGATION

KW - MODEL

KW - TROPOSPHERE

KW - VARIABILITY

U2 - 10.1002/2013JD020138

DO - 10.1002/2013JD020138

M3 - статья

VL - 119

SP - 1340

EP - 1355

JO - Journal of Geophysical Research D: Atmospheres

JF - Journal of Geophysical Research D: Atmospheres

SN - 2169-897X

IS - 3

ER -