Accueil > Actualités > Séminaires > Séminaire d'Isaac Held


Titre : Tropical upper tropospheric warming trends and hurricane frequency
Nom du conférencier : Isaac Held
Son affiliation : GFDL
Laboratoire organisateur : LMD
Date et heure : 31-03-2014 10h30
Lieu : UPMC - 4 place Jussieu - Paris 5e - Tour Zamansky - 24e étage - Salle 2400
Résumé :

A long standing controversy has centered on temperature trends in the tropical upper troposphere during the satellite era. Coupled models on average warm far more than any observational estimates over this period, while even AMIP simulations with observed SSTs (almost all) warm too much. I will show that upper tropospheric trends in AMIP simulations are sensitive to the SST data used as a boundary condition. Examining an atmospheric model that produces realistic hurricane frequencies, we find that different SST data sets also produce differing trends in Atlantic hurricane frequency. The SST data set that results in the smallest upper tropospheric temperature trend results in more realistic hurricane trends as well. I will also briefly discuss the bias introduced in upper tropospheric trends by uncoupling atmosphere from ocean as in these AMIP simulations.


Merci de penser à apporter votre carte d'identité pour pénétrer dans la Tour Zamansky.

Contact :

MP Lefebvre, LMD