Climate Dynamics

, Volume 39, Issue 9, pp 2361–2375

Breaking down the tropospheric circulation response by forcing

  • Paul W. Staten
  • Jonathan J. Rutz
  • Thomas Reichler
  • Jian Lu
Article

DOI: 10.1007/s00382-011-1267-y

Cite this article as:
Staten, P.W., Rutz, J.J., Reichler, T. et al. Clim Dyn (2012) 39: 2361. doi:10.1007/s00382-011-1267-y

Abstract

This study describes simulated changes in the general circulation during the twentieth and twenty-first centuries due to a number of individual direct radiative forcings and warming sea surface temperatures, by examining very long time-slice simulations created with an enhanced version of the Geophysical Fluid Dynamics Laboratories Atmospheric Model AM 2.1. We examine the effects of changing stratospheric ozone, greenhouse gas concentrations, and sea surface temperatures individually and in combination over both hemispheres. Data reveal robust poleward shifts in zonal mean circulation features in present-day simulations compared to a pre-industrial control, and in future simulations compared to present-day. We document the seasonality and significance of these shifts, and find that the combined response is well approximated by the sum of the individual responses. Our results suggest that warming sea surface temperatures are the main driver of circulation change over both hemispheres, and we project that the southern hemisphere jet will continue to shift poleward, albeit more slowly during the summer due to expected ozone recovery in the stratosphere.

Keywords

Global climate modelingGeneral circulationStratosphere/troposphere interactions

Abbreviations

20C3M

Twentieth century AR4 simulation

AM

Annular mode

AM2.1

Atmospheric Model v. 2.1

AR4

Fourth assessment

CAM3

Community Atmosphere Model version 3

CCM

Coupled chemistry climate models

CM2.1

Climate model version 2.1

CMAM

Canadian Middle Atmosphere Model

CMIP3

Coupled Model Intercomparison Project

DJF

December, January, and February

DP09

Deser and Phillips (2009)

ERA-40

European Centre for Medium-Range Weather Forecasts 40 Year Re-analysis Project

GFDL

Geophysical Fluid Dynamics Laboratory

IPCC

Intergovernmental Panel on Climate Change

ITCZ

Intertropical convergence zone

JJA

June, July, and August

K11

Kang et al. (2011)

NAM

Northern annular mode

NCAR

National Center for Atmospheric Research

NH

Northern hemisphere

P11a

Polvani et al. (2011a)

P11b

Polvani et al. (2011b)

P–E

Precipitation–evaporation

SAM

Southern annular mode

SH

Southern hemisphere

SST

Sea surface temperature

Supplementary material

382_2011_1267_MOESM1_ESM.eps (537 kb)
Supplementary Figure S1 As with Figure 2 but for June-July-August (EPS 536 kb)
382_2011_1267_MOESM2_ESM.eps (857 kb)
Supplementary Figure S2 As with Figure 3 but for June-July-August (EPS 857 kb)
382_2011_1267_MOESM3_ESM.eps (626 kb)
Supplementary Figure S3 Left column as with Figure 2 and right column as with Figure 3, but for changes between present-day and the year 2100 (EPS 626 kb)

Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  • Paul W. Staten
    • 1
  • Jonathan J. Rutz
    • 1
  • Thomas Reichler
    • 1
  • Jian Lu
    • 2
  1. 1.Department of Atmospheric SciencesUniversity of UtahSalt Lake CityUSA
  2. 2.IGES/COLA, Center for Ocean-Land-Atmosphere StudiesCalvertonUSA