Academic Commons

Articles

Is the poleward migration of tropical cyclone maximum intensity associated with a poleward migration of tropical cyclone genesis?

Daloz, Anne Sophie; Camargo, Suzana J.

A recent study showed that the global average latitude where tropical cyclones achieve their lifetime-maximum intensity has been migrating poleward at a rate of about one-half degree of latitude per decade over the last 30 years in each hemisphere. However, it does not answer a critical question: is the poleward migration of tropical cyclone lifetime-maximum intensity associated with a poleward migration of tropical cyclone genesis? In this study we will examine this question. First we analyze changes in the environmental variables associated with tropical cyclone genesis, namely entropy deficit, potential intensity, vertical wind shear, vorticity, skin temperature and specific humidity at 500 hPa in reanalysis datasets between 1980 and 2013. Then, a selection of these variables is combined into two tropical cyclone genesis indices that empirically relate tropical cyclone genesis to large-scale variables. We find a shift toward greater (smaller) average potential number of genesis at higher (lower) latitudes over most regions of the Pacific Ocean, which is consistent with a migration of tropical cyclone genesis towards higher latitudes. We then examine the global best track archive and find coherent and significant poleward shifts in mean genesis position over the Pacific Ocean basins.

Geographic Areas

Files

  • thumnail for Daloz_Camargo_ClimDyn2018_10.1007-2Fs00382-017-3636-7.pdf Daloz_Camargo_ClimDyn2018_10.1007-2Fs00382-017-3636-7.pdf application/pdf 95.1 MB Download File

Also Published In

Title
Climate Dynamics
DOI
https://doi.org/10.1007/s00382-017-3636-7

More About This Work

Academic Units
Lamont-Doherty Earth Observatory
Published Here
March 26, 2019

Notes

Keywords: Tropical cyclone genesis, Poleward migration, Tropical cyclone genesis index, Observations

Academic Commons provides global access to research and scholarship produced at Columbia University, Barnard College, Teachers College, Union Theological Seminary and Jewish Theological Seminary. Academic Commons is managed by the Columbia University Libraries.