This interesting infographic comes from the University of San Francisco and looks at the changing roles of social media and disaster response. Nearly 870,000 people annually are affected by disasters each year, but social media is having a huge impact on how survivors are able to communicate with one another, as well as with authorities.
One point on the infographic even states that "during disasters, social networks often replace 911 as the go-to source for help." This has been proven most recently by Hurricane Sandy, where Twitter became an invaluable tool for the Federal Emergency Management Agency (FEMA) and Red Cross to communicate with people in need of assistance. It's estimated that if a person reaches out on social media for help, aid will come to them in about 60 minutes.