In recent years we have witnessed several changes in the behavior of meteorological events due to climate change. With the increase in ocean temperatures and the warm phase of the ENSO phenomenon, the necessary conditions have been created for the origin of the strongest hurricane ever recorded on the Pacific coast. Hurricane Otis arrived on October 25, 2023, registering sustained winds of 270 kilometers per hour and with an increase in hurricane strength from tropical storm to category 5 hurricane on the Saffir-Simpson scale in a record time of 12 hours.
In areas where self-built housing is predominant, the adverse effects caused by Hurricane Otis were intensified in front of the more urbanized areas. In addition, the lack of anticipation in the implementation of adequate civil protection protocols for a meteorological phenomenon of this magnitude contributed significantly to the magnification of the damages caused in general. According to the Mexican Association of Insurance Institutions (AMIS), 13,827 homes were reported with damages and 94 hotel claims for an amount of 8,178 million pesos. Regarding maritime damages, 203 vessels reported damages for an amount of 883 million pesos. Concerning damages to the education sector, on December 5, 2023, the head of the Secretary of Education of Guerrero (SEG) Marcial Rodríguez Saldaña confirmed damages to 403 elementary schools in the municipalities of Acapulco de Juárez and Coyuca de Benitez.
In this context, after the impact of the hurricane, the first need detected between the local authorities of Guerrero and the Humanitarian OpenStreetMap Team (HOT) staff was to generate a georeferenced and updated base layer of buildings and roads in the bay of Acapulco, but also in its surroundings. This will enable decision-makers to implement better measures to understand the magnitude of the disaster, as well as to elaborate potential coordinated responses in specific territories.
For eventualities of this nature, HOT is responsible for initiating a mapping "activation" on its Tasking Manager platform, which distributes small territory grids where mappers can identify buildings and roads from satellite imagery. This measure not only helps to provide greater order and control in the work generated but also allows the coordinated and simultaneous participation of a large number of mappers around the world.
To meet the needs of the Acapulco project, 755 tasks were established along the bay and around the city to ensure the identification of infrastructure, even in the most remote locations of the urban node. For this purpose, ESRI World Imagery was used as a reference, which is the most recent and with the highest definition for mapping.
Simultaneously with the mapping of the base layer, the local authorities generated photomaps using drones in some priority areas, aiming to obtain post-disaster images that would also be of good quality for interpretation. Thus, in a second instance, another project would be generated through the Tasking Manager for a mapping exclusively of buildings and equipment visibly damaged by the hurricane.
Response from the Mexican Chapters
Once the Guerrero project was enabled in the Tasking Manager, the YouthMappers chapters in Mexico coordinated to call for a Mapathon week, not only to encourage mapping but also for the training of mappers capable of contributing to the mapping of the affected areas. In response to the needs of the first stage, a call was disseminated through Instagram and X (formerly Twitter) to publicize the schedules and registration form. The introductory week to humanitarian mapping consisted of learning how to use OpenStreetMap; creating an account, getting to know the ID Editor mapping tools, and good practices in element identification and tagging. Some exercises were carried out to identify mapping errors and doubts were shared. Subsequently, they focused on learning how to collaborate on a project in HOT's Tasking Manager, understanding the instructions required for each mapping project and the impact of generating geographic information of areas that are difficult to access or in disaster situations, emphasizing the importance of carrying out the mapping in detail.
During this week of training, it was necessary to create a space adapted to the different profiles of the people interested in mapping. Many of the people who joined the training week were familiar with Geographic Information Systems, being certain of the potential of having access to an updated and detailed cartographic base. In this same space, there were designers, programmers, or workers who had not had such an approach to cartographic work, which generated a space for questions that were answered not only by the facilitators but also by the participants themselves, which allowed them to have a better appropriation of the activity they were carrying out. Finally, given the demand and recurrence of participants, it was decided to extend the workshops and mapping sessions for another two weeks.
In order to attend to the second stage of the project, the Latin American Open Mapping Hub also coordinated training for mappers to work on priority affected areas. In this stage, post-disaster images would be interpreted with new criteria and indications, such as using the building:destroyed=yes label to distinguish only buildings with visible damage to their structure. Although in this second stage, there was a decrease in the presence of mappers in our sessions, their participation was maintained asynchronously supported through a WhatsApp group where progress was shared, but also specific doubts, allowing us to maintain the quality of the mapping with the advice of the mappers themselves.
Participation of allies
As a gesture of solidarity and partnership, the GeoMap ESPE Chapter of Ecuador joined the efforts for the mapping of post-disaster images. Almost at the same time as the arrival of Hurricane Otis to Acapulco, several members of UAMaps and UEAMex were trained to participate in the Risk Management Mapathon in the Ecuadorian territory. This collaboration took place due to the interest of the Mexican chapters in natural disaster risk management, since Hurricane Otis made landfall on the same dates that these trainings took place, knowing that soon it would be Mexico's turn to be activated. On the other hand, the participation of students affiliated with the National Network of Geography Students (RENEG) was also crucial. They were convened by its president, Alexis Sanchez, who also serves as vice president at UAMaps. These students took advantage of their previous knowledge in cartography and their concern for the situation in Guerrero, which contributed significantly both to the mapping during the mapathons and to the dissemination of the activities through the information channels of their respective universities. Among them, the collaboration of the Universidad de Guadalajara, Universidad de Guanajuato, Universidad Autónoma Metropolitana Unidad Iztapalapa and UNAM ENES Morelia stands out. The inclusion of the Network in HOT's activities created an important precedent that will promote a more constant presence of the geography guild at the national level, and will also foster institutional ties that will allow for a more effective response capacity in future eventualities.
Results and balance of the mapping
The Acapulco base layer mapping process was completed within an impressive 19 days (which, in comparison to other activations in other parts of the world, is considered quite fast). In total, 52,743 buildings were identified along the map of Acapulco and approximately 628 km of roads. Participation in the task involved the efforts of 175 mappers and 22 validators. However, one of the indicators that gave us the most satisfaction was the level of experience of the participating mappers, highlighting 78% of users with a beginner level and particularly 42% of mappers with less than 3 months of participation in HOT Tasking Manager. Thus, almost half of the people who contributed to the humanitarian response were new mappers, mobilized by the noise and dissemination generated by the different mapping communities. Thus, we would not only be referring to people who contributed to the recovery of Acapulco in a virtual and direct way, but who are now also users sensitized to the importance of humanitarian mapping, with open access, and who have the knowledge to continue participating in other Tasking Manager activations in emergencies in different parts of the world.
Data available for Acapulco in OpenStreetMap before and after mapping activations.
As the weeks passed, new actors in academia expressed interest in joining the efforts of local authorities, who had identified new needs for the design of economic recovery plans and priority infrastructure. In this way, a coordinated group would emerge between HOT and five universities from different areas of Mexico, including the Universidad Autónoma Metropolitana Unidad Cuajimalpa, Universidad Autónoma del Estado de México, Universidad de Guanajuato, Universidad Autónoma de Ciudad Juárez (UACJ) and Universidad Autónoma de Guerrero.
Among the priority actions assigned to this group, was the need to map strategic facilities for citizens and the local economy, such as schools (from kindergartens to universities), health centers (hospitals and clinics), and public markets. With the purpose of obtaining more complete information on the potential infrastructure affected by the hurricane, but also the recognition of possible areas that could be used as collection centers in the recovery strategies and citizen attention. This infrastructure would not only be georeferenced but also tagged and mapped with OSM standards (extension of the property, identification of open or recreational spaces, parking lots, etc.). For this exercise, volunteers were first trained to ensure consistency in data quality and, in addition, a layer control and assignment matrix was required (similar to the functioning of HOT's Tasking Manager) whose follow-up was coordinated by the UAMaps chapter. The operation was based on the fact that each volunteer could choose a layer with the georeferenced sites and thus map them in the OSM ID Editor asynchronously.
As a result of the efforts made by 17 student volunteers in a period of one month, nearly 1,000 sites with strategic infrastructure were mapped: around 700 educational facilities in Acapulco de Juárez, using official information from the National Statistical Directory of Economic Units (DENUE) and a layer belonging to local authorities, which contemplated facilities located in the periphery of the municipality; 170 health centers mapped in both Acapulco de Juárez and Coyuca de Benítez, belonging to the Catalog of Health Facilities; and finally, the 53 public markets in Acapulco de Juárez and Coyuca de Benítez mentioned by the DENUE.
Reflections and lessons learned
Through our participation in the organization, coordination and training of the humanitarian mapping projects in Guerrero, a series of valuable reflections and lessons learned have emerged that we would like to highlight so that our mapping colleagues can consider them in their current and future mapping activities.
First, one of the most recurrent difficulties for mappers (at all levels) was understanding the instructions requested for the post-disaster imagery tasks. Although these were sufficiently precise and detailed, many colleagues pointed out that they were described in English, causing misinterpretations. Therefore, in addition to establishing this content in a greater diversity of languages, it would be good to accompany the instructions with more visual reference material (photos or short videos on YouTube explaining the minimum parameters of the expected mapping), particularly when tags or procedures are going to be used, which are not very common in the OSM communities.
Regarding the management of the diverse mapping groups, we also identified that it is key to maintain the most personalized and individual communication possible with the participants. In this way, a smoother link is generated to discuss small doubts and ensure a more prolonged commitment to the efforts. However, we also note that it is not enough to have such approaches if we do not also share news and progress of what the authorities are doing with the information generated by the volunteers. To materialize and expose the results of the effort is decisive to keep the spirits and interest in continuing to support the cause.
The impact of Otis in Guerrero was also a gateway that led people who are not involved in mapping to learn about and participate directly in supporting situations in which they are sensitive and empathetic. This type of mapping has been attractive to them because of its remote and asynchronous possibilities, particularly for those who do not have flexible time during their work or student days, nor can relate to these resources and knowledge in depth. As facilitators and organizers, this panorama has made us reflect and be more conscious in continuously considering the conditions in which we generate spaces for people with these characteristics. Incorporating complementary content sources such as video tutorials, WhatsApp/Telegram groups or personalized follow-ups are alternatives that can be quite practical and simple to carry out.
Likewise, it is considered essential to promote and strengthen further collaboration between the local mapping communities, OSM and YouthMappers in order to have greater reach in mapping activities. Linking with students through networks and various outreach spaces, such as the National Network of Geography Students (RENEG) or other academic institutions, not only leads to an increase in the number of volunteers but also opens opportunities to influence the training of professionals and students in the field of geography. This allows them to maintain a more sustained support network in the long term, but at the same time, there would be more possibilities for participants to appropriate this knowledge and tools to transcend them into projects of even greater impact.
In sum, this experience represented a great opportunity to put into practice all the knowledge and skills that characterize us as university students and proactive young people in the YouthMappers network. We thank the entire team of the Latin American Open Mapping Hub for considering us a strong ally in the face of the emergency and allowing us to interact from different fronts, which have greatly enriched the way in which our organizations can now contribute to future eventualities. This challenge also meant expanding our horizons of collaboration, towards new topics, allies and friends. Thank you to everyone involved.