#  Harvard Climate Seminar: Lorenzo Polvani 

 



####  calendar\_today Date and Time 

 **February 7, 2018** 

 12:00PM - 12:00PM EST 

####  pin\_drop Location 

 **HUCE MCZ 440**  



 

 



 

**[Lorenzo Polvani](http://apam.columbia.edu/lorenzo-polvani)** Professor of Applied Mathematics and Earth & Environmental Sciences Columbia University **Why has the lower stratosphere stopped cooling for the last 20 years?**

 The cooling of the stratosphere is an important fingerprint of CO2 on the climate system. This stratospheric signature of CO2, however, is confounded by the presence of ozone-depleting substances (ODS). The talk will summarize the latest observations and, with simple arguments and with the help of ensembles of chemistry-climate model integrations, demonstrate the crucial role of ODS not only on stratospheric temperature trends, but also on the entire large-scale circulation of the stratosphere.

   ![Polvani_Image](/sites/g/files/omnuum11466/files/styles/hwp_1_1__720x720_scale/public/climate/files/fig.png?itok=0r7Ocn_D) 

 



 

 



 

 See also:- [ Harvard Climate Seminar ](/type-event/climate-seminar)
- [ 2018 ](/climate-seminars/2018)
 
 

 Share on:- [     Facebook ](#)
- [     Twitter ](#)
- [     Linkedin ](#)
 


 Save: [ Add to calendar calendar\_today ](https://climate.fas.harvard.edu/node/1204231/event-feed.ics)  Copy link link