Tweeting tornadoes and other disasters

Follow the Twitter feed of the Christian relief organization World Vision, and you’ll find updates on floods in Sri Lanka, a cholera outbreak in Haiti, a volcanic eruption in Indonesia.

“#BrazilFlooding ‘disproportionately affected the poor, who live on hillsides and outskirts of town and r more vulnerable,'” reads one tweet at its handle for the press, @WorldVisionNews.

The revolution in communication isn’t limited to major corporations with a social media budget. It is changing the way relief organizations and local governments inform the public and drum up volunteers and contributions during emergencies.

Cities are posting updates during hurricanes and forest fires, and the New Zealand Blood Service is advising friends on Facebook where they can donate blood after this week’s earthquake.

During this month’s major blizzard, the American Red Cross of Greater Chicago used Twitter to tell motorists stranded on Lake Shore Drive how to stay safe and make themselves visible to rescuers, says Chicago-based spokeswoman Martha Carlos.

Red Cross tweets