“Social media has been established in many larger emergencies and crises. This process has not started just a few years ago, but already 15 years ago in 2001 after the terrorist attacks of 9/11. In the following years, especially in the last 10, sometimes summarized under the term crisis informatics, a variety of studies focusing on the use of ICT and social media before, during or after nearly every crisis and emergency has arisen.”
Source: Reuter, C., & Kaufhold, M. A. (2018). Journal of Contingencies and Crisis Management and available from this link (subscription journal).