TY - JOUR
T1 - Sensitivity of the Latitude of the Westerly Jet Stream to Climate Forcing
AU - Chen, Gang
AU - Zhang, Pengfei
AU - Lu, Jian
N1 - Funding Information:
We thank Chengji Liu for his assistance in setting up the overriding model. We would like to acknowledge high-performance computing support from Cheyenne (https://doi.org/10.5065/D6RX99HX) provided by NCAR's Computational and Information Systems Laboratory, sponsored by the NSF. We acknowledge the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modeling groups (listed in Appendix) for producing and making available their model output. For CMIP the U.S. Department of Energy's Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portals. The GFDL atmospheric dynamical core is available online (at https://www.gfdl.noaa.gov/idealized-spectral-models-quickstart/). Postprocessed data used in this study are available online (at https://doi.org/10.6084/m9.figshare.11752779.v1). G. C. and P. Z. are supported by National Science Foundation grants AGS-1742178 and AGS-1832842. J. L. is supported by the U.S. Department of Energy Office of Science Biological and Environmental Research as part of the Regional and Global Modeling and Analysis program.
Publisher Copyright:
©2020. American Geophysical Union. All Rights Reserved.
PY - 2020/2/28
Y1 - 2020/2/28
N2 - The latitude of the westerly jet stream is influenced by a variety of climate forcings, but their effects on the jet latitude often manifest as a tug of war between tropical forcing (e.g., tropical upper-tropospheric warming) and polar forcing (e.g., Antarctic stratospheric cooling or Arctic amplification). Here we present a unified forcing-feedback framework relating different climate forcings to their forced jet changes, in which the interactions between the westerly jet and synoptic eddies are synthesized by a zonal advection feedback, analogous to the feedback framework for assessing climate sensitivity. This framework is supported by a prototype feedback analysis in the atmospheric dynamical core of a climate model with diverse thermal and mechanical forcings. Our analysis indicates that the latitude of a westerly jet is most sensitive to the climate change-induced jet speed changes near the tropopause. The equatorward jet shift also displays a larger deviation from linearity than the poleward counterpart.
AB - The latitude of the westerly jet stream is influenced by a variety of climate forcings, but their effects on the jet latitude often manifest as a tug of war between tropical forcing (e.g., tropical upper-tropospheric warming) and polar forcing (e.g., Antarctic stratospheric cooling or Arctic amplification). Here we present a unified forcing-feedback framework relating different climate forcings to their forced jet changes, in which the interactions between the westerly jet and synoptic eddies are synthesized by a zonal advection feedback, analogous to the feedback framework for assessing climate sensitivity. This framework is supported by a prototype feedback analysis in the atmospheric dynamical core of a climate model with diverse thermal and mechanical forcings. Our analysis indicates that the latitude of a westerly jet is most sensitive to the climate change-induced jet speed changes near the tropopause. The equatorward jet shift also displays a larger deviation from linearity than the poleward counterpart.
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U2 - 10.1029/2019GL086563
DO - 10.1029/2019GL086563
M3 - Article
AN - SCOPUS:85081076388
SN - 0094-8276
VL - 47
JO - Geophysical Research Letters
JF - Geophysical Research Letters
IS - 4
M1 - e2019GL086563
ER -