Why are Canadian wildfires affecting the U.S.?

There are anomalies that help explain why smoke from 400 Canadian wildfires is causing such havoc in the United States. Correspondent David Pogue talks with climate and health scientist Vijay Limaye, of the Natural Resources Defense Council, about why this may be a sign of things to come. #wildfireseason #airqualityindex "CBS Sunday Morning" features stories on the arts, music, nature, entertainment, sports, history, science and Americana, and highlights unique human accomplishments and achievements. Check local listings for CBS Sunday Morning broadcast times. Subscribe to the "CBS Sunday Morning" YouTube channel: http://bit.ly/20gXwJT Get more of "CBS Sunday Morning": http://cbsn.ws/1PlMmAz Follow "CBS Sunday Morning" on Instagram: http://bit.ly/23XunIh Like "CBS Sunday Morning" on Facebook: https://bit.ly/3sRgLPG Follow "CBS Sunday Morning" on Twitter: http://bit.ly/1RquoQb Subscribe to our newsletter: http://cbsn.ws/1RqHw7T Download the CBS News app: http://cbsn.ws/1Xb1WC8 Try Paramount+ free: https://bit.ly/2OiW1kZ For video licensing inquiries, contact: [email protected]