Media playback is unsupported on your device

US drought and dust storms affect crops

2 July 2014 Last updated at 22:11 BST

Parts of the United States are experiencing the worst drought for decades, with farmers warning that harvests are being badly hit.

The state of Oklahoma has endured persistent drought for the past three-and-a-half years and people there are fearful of a return of the so-called Dust Bowl conditions of the 1930s.

The BBC's science editor David Shukman visited one of the worst-affected areas, known as the Oklahoma Panhandle.

Copyright © 2015 BBC. The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.