CaltechAUTHORS
  A Caltech Library Service

Storm Track Shifts under Climate Change: What Can Be Learned from Large-Scale Dry Dynamics

Mbengue, Cheikh and Schneider, Tapio (2013) Storm Track Shifts under Climate Change: What Can Be Learned from Large-Scale Dry Dynamics. Journal of Climate, 26 (24). pp. 9923-9930. ISSN 0894-8755. http://resolver.caltech.edu/CaltechAUTHORS:20140106-112443566

[img]
Preview
PDF - Published Version
See Usage Policy.

535Kb

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20140106-112443566

Abstract

Earth’s storm tracks are instrumental for transporting heat, momentum, and moisture and thus strongly influence the surface climate. Climate models, supported by a growing body of observational data, have demonstrated that storm tracks shift poleward as the climate warms. But the dynamical mechanisms responsible for this shift remain unclear. To isolate what portion of the storm track shift may be accounted for by large-scale dry dynamics alone, disregarding the latent heat released in phase changes of water, this study investigates the storm track shift under various kinds of climate change in an idealized dry general circulation model (GCM) with an adjustable but constant convective stability. It is found that increasing the mean surface temperature or the convective stability leads to poleward shifts of storm tracks, even if the convective stability is increased only in a narrow band around the equator. Under warming and convective stability changes roughly corresponding to a doubling of CO_2 concentrations from a present-day Earthlike climate, storm tracks shift about 0.8° poleward, somewhat less than but in qualitative agreement with studies using moist GCMs. About 63% (0.5°) of the poleward shift is shown to be caused by tropical convective stability variations. This demonstrates that tropical processes alone (the increased dry static stability of a warmer moist adiabat) can account for part of the poleward shift of storm tracks under global warming. This poleward shift generally occurs in tandem with a poleward expansion of the Hadley circulation; however, the Hadley circulation expansion does not always parallel the storm track shift.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1175/JCLI-D-13-00404.1DOIArticle
http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-13-00404.1PublisherArticle
ORCID:
AuthorORCID
Schneider, Tapio0000-0001-5687-2287
Additional Information:© 2013 American Meteorological Society. Manuscript received 10 July 2013, in final form 2 October 2013. We are grateful for the financial support provided by the National Science Foundation (Grant AGS-1019211) and for helpful discussions with Xavier Levine.
Funders:
Funding AgencyGrant Number
NSFAGS-1019211
Subject Keywords:Storm tracks; Climate change
Record Number:CaltechAUTHORS:20140106-112443566
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20140106-112443566
Official Citation:Mbengue, Cheikh, Tapio Schneider, 2013: Storm Track Shifts under Climate Change: What Can Be Learned from Large-Scale Dry Dynamics. J. Climate, 26, 9923–9930. doi: http://dx.doi.org/10.1175/JCLI-D-13-00404.1
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:43227
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:09 Jan 2014 16:23
Last Modified:18 Mar 2015 21:45

Repository Staff Only: item control page