“Who and Where needs help?” is the most important question to be answered after a disaster hit, especially for the emergency relief and aid organizations, so that resources and supplies could be effectively and efficiently distributed to those in desperate need. However, such kind of information is difficult to know, in particular the developing countries, due to the lack of systematic plan, comprehensive database of assets, population or infrastructure. Therefore, the demand for spatial information has greatly increased, and considering the urgent needs of emergency relief operations, crowdsourcing and volunteered geographic information (VGI) has become quite important in the data collection and creation of online maps.
With the efforts of volunteer community, it has become possible to provide meaningful assistance in disaster response by contributing in mapping. A large number of maps could be produced within a short period of time, undoubtedly helping the emergency relief and aid services. One of the successful examples was the Haiti earthquake, where OpenStreetMap volunteers from around the world mapped interested areas using satellite images and this work was complemented by on-the-ground volunteers in Haiti to provide additional local information . For the recent Nepal earthquake in April 2015, OpenStreetMap was also used to map physical infrastructures and affected earthquake zones to provide support for the coordination of rescue and relief operations . Another example is the Ushahidi project , which offers the ability to report geo-located urgent short messages and reports through mobile phones or internet. This collected information is then used later by the relief workers to rapidly locate individuals and communities in most need. Another open source solution is the Sahana, an open source disaster management system, which provides tools to help in managing coordination and collaboration problems for organizations and communities. Its major functions are to support the search for missing persons, the sharing and reporting of information, the coordination of relief efforts and donations, and the tracking and managing of help requests.
In addition, a number of benefits were derived from such web and disaster mapping services including the possibilities to allow individuals in reporting of local and specific conditions. For example, applications and features such as Google’s Person Finder or Facebook’s Safety Check were activated and deployed for the recent Nepal earthquake to support in search of individuals or notify one’s safety to the family members and friends. Moreover, Twitter platform has been used extensively and proven useful in crisis situations by individuals, volunteers, rescue workers and authorities. It also offers a SMS service (in more than 90 countries and via satellite phone), and therefore, one can tweet from mobile devices through SMS in urgent situations. One can stay informed and share the important information without relying on Internet connectivity during a crisis.
Figure: How to automatically classify text messages (or tweets) for disaster response (source: http://irevolution.net)
Regardless of the great benefits of advanced technologies, there are also cases where the impacted zone have power loses without internet connections, and thus, access to relevant information are still limited. However, for those managing relief efforts, the derived benefits are enormous thanks to the shared and coordinated volunteering efforts in crowdsourcing disaster relief, while the accuracy and validity of crowd-sourced data should still be cross-checked for the better use of collected information. The ways of handling and analysis of huge amount of data generated by affected communities should also be explored to ensure the efficient use of available information during and after the disaster.