CONTEXT

Hurricane Melissa made landfall in Jamaica on October 28, 2025, causing widespread damage to buildings, infrastructure, and livelihoods across Jamaica and affecting parts of Cuba and Haiti. In the immediate aftermath, local authorities and humanitarian actors faced significant data gaps: there was no comprehensive, up-to-date information on damaged buildings, impacted communities, or priority areas for response.

This data gap directly affected the ability of governments and responders to allocate resources efficiently, monitor household support programs, and coordinate relief operations. Local stakeholders, including Jamaica Flying Labs, national emergency GIS teams, and disaster management agencies, identified the urgent need for reliable, openly accessible geospatial data to inform response and recovery efforts.

Without rapid mapping and validation, affected communities risked delayed assistance, duplicated efforts, and inequitable distribution of aid. HOT’s role was critical in mobilizing global and regional mapping communities, activating open-source tools, and translating citizen-reported and remotely sensed data into actionable datasets that could be directly integrated into governmental and humanitarian workflows.

APPROACH

HOT implemented a multi-layered humanitarian mapping approach that combined anticipatory coordination, remote data collection, local engagement, and technical validation. Prior to landfall, HOT coordinated with regional partners including Jamaica Flying Labs (JFL), ODPEM, NERGIST, CDEMA, and the Caribbean School of Data to anticipate data needs and establish rapid-response channels.

Following the hurricane, HOT activated multiple tools and methodologies:

• ChatMap was deployed through moderated WhatsApp groups to collect real-time, citizen-reported information on building damage and household needs. Volunteers manually geolocated reports and integrated them into uMap and ESRI systems used by government agencies.
• Tasking Manager projects were launched for damage assessment and building mapping in Jamaica and Cuba, leveraging NOAA and Maxar satellite imagery. Due to the complexity of damage interpretation, mapping was limited to intermediate and advanced contributors.
• MapSwipe supported rapid identification of damaged or missing structures to prioritize Tasking Manager workflows.
• Drone Tasking Manager coordinated drone flights conducted by Jamaica Flying Labs, with imagery uploaded to OpenAerialMap for open access and further analysis.
  

To accelerate participation and improve data quality, HOT simplified damage tagging to a single binary indicator (damage=yes) and prioritized the use of high-resolution imagery. Collaboration across governments, universities, NGOs, and volunteer networks, including YouthMappers and the LAC Humanitarian Mapping Brigade, was central to the project’s success. HOT’s technical expertise, community infrastructure, and neutral convening role enabled rapid scaling and cross-platform integration.

OUTCOME AND IMPACT

The Hurricane Melissa response generated critical open datasets that directly supported governmental and humanitarian decision-making. In Jamaica, ChatMap data provided real-time situational awareness and was integrated into ESRI systems used by the National Spatial Data Management Branch, which described the data as “invaluable” for monitoring building damage and household support.

Across the region, the activation resulted in:

• Over 247 mappers contributing to damage assessment and validation workflows.
• 234 geolocated reports collected through ChatMap in Jamaica.
• Multiple Tasking Manager projects completed or nearing completion across Jamaica and Cuba.
• Drone imagery collected and openly shared via OpenAerialMap.
• Building footprint and damage datasets delivered to the International Disaster Charter platform for Cuba.

Beyond immediate response, the project strengthened institutional capacity by demonstrating the value of open mapping tools. The Jamaican government initiated discussions to develop a dedicated ChatMap platform for tracking household recovery support, signaling long-term adoption of the approach.

LESSONS LEARNED AND NEXT STEPS

The response highlighted the critical importance of early access to high-quality imagery, simplified mapping instructions, and clear scope definition. Initial challenges with cloud cover, imagery resolution, and complex tagging slowed early progress, underscoring the need for pre-approved imagery pipelines and streamlined protocols.

Security considerations within open communication platforms reinforced the necessity of clear participation rules and moderation before public rollout. Drone deployment, while valuable, remains resource-intensive and requires clearer standards, earlier government coordination, and dedicated processing capacity.

Next steps include improving anticipatory imagery access, refining damage-mapping methodologies, expanding ChatMap training in French and Spanish, and strengthening regional protocols for drone-based assessments to support future Caribbean disaster responses.