GHHIN Welcomes New Extreme Heat Services Technical Advisor

Published: September 23, 2025

Global Heat Health Information Network

The Global Heat Health Information Network (GHHIN) is pleased to welcome Mr. Armel Castellan as Extreme Heat Services Technical Advisor, based at the World Meteorological Organization (WMO) and member of the GHHIN Technical Support Unit.

 

New Role to Advance Extreme Heat Services Globally

 

The World Meteorological Organization has appointed Armel to a new role within its GHHIN technical support unit, where he will help countries and partners expand their capacity to deliver extreme heat services. He will lead support for the rollout of WMO’s Extreme Heat Services Roadmap, provide technical guidance to national meteorological and hydrological services worldwide, and strengthen global partnerships on heat risk science and services.

 

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Lessons From the Frontlines of Climate Emergencies

 

Armel brings a strong scientific and operational background to his new role, with a foundation in Atmospheric Sciences and two decades of experience in Canada at the intersection of extreme weather services and emergency management. His expertise spans impact-based forecasting, early warning systems, and stakeholder collaboration, grounded in both technical knowledge and practical, on-the-ground operations.

 

Most recently in his work as a Senior Advisor to the Director General of Policy, Planning and Partnerships and previously as a Warning Preparedness Meteorologist with Environment and Climate Change Canada (ECCC), Armel worked closely with emergency managers, health authorities, infrastructure operators, and local officials to turn forecasts into practical warnings that help communities prepare for extreme weather.

 

As a lead collaborator to the Provincial/Federal Emergency Management Organizations and Health partners, and spokesperson for ECCC to the media, Armel was at the forefront of Canada’s reckoning with extreme heat in June 2021, when temperatures reached 49.6°C in Lytton, British Columbia, shattering national records by almost 5°C. Within a day the town was destroyed by wildfire, and across British Columbia more than 700 people lost their lives to extreme heat. The cascading impacts continued in the following season as drought- and fire-damaged landscapes buckled under catastrophic flooding, costing human lives and the lives of hundreds of thousands of animals, evacuating entire towns, cutting off Vancouver by road and rail, and causing billions in damages.

 

“Throughout my career I’ve witnessed the devastating impacts of extreme heat firsthand. Even in Canada, temperatures can reach 50°C – and the toll on all living organisms, natural environment, infrastructure and the economy is very real, is often tragic but also preventable,” said Armel, “At the same time, I’ve seen how effective warnings and strong policies save lives and societal costs. Experiencing this work at the national level in Canada has inspired me to bring my skills to the global stage, through WMO, GHHIN and with country partners worldwide, to help ensure as many people as possible are protected from extreme heat.”

 

This direct experience with the human and systemic costs of compounding climate extremes underlines the expertise Armel brings to the World Meteorological Organization and the Global Heat Health Information Network. His appointment reflects a shared commitment to expanding impact-based extreme heat services worldwide, ensuring that communities everywhere are better protected from rising heat.