Weather4UN – Supporting humanitarian decision-making with impact estimates

Most disasters triggered by natural hazards and leading to humanitarian crises are caused by extreme weather- and climate-related events. Between 1970 and 2019, there were more than 11’000 disasters attributed to weather, climate and water-related hazards, resulting in over 2 million deaths and 3.64 trillion US dollars in losses. To further reduce the impacts of these hydrometeorological events, it is increasingly crucial that humanitarian organizations take anticipatory action before crises as well as responding during or after the events.

More is to be done to harness reliable and timely hydrometeorological information to support Anticipatory Action and Response. The WMO Coordination Mechanism (WCM) aims is to facilitate the access to authoritative information and expert advice in case of hydromet events to support the humanitarian community and Anticipatory Action. The WCM is an interface between WMO and its Members and the humanitarian community and thus is a key element of the Early Warning for All initiative. Under the coordination of the WMO Secretariat, all National Meterorological and Hydrological Services are invited to contribute to the WCM. Switzerland has replied to that call through a dedicated project, so-called, Weather4UN.

In the project, we develop prototypes for impact estimates based on weather forecasts of WMO Members and WMO Regional Climate Centers to support the decision making of the UN and other humanitarian agencies. This information is tailored to best meet the needs of these humanitarian actors. The HydroMet Impact Outlook estimates the humanitarian impacts of the forecasted hazard events for decision-support of the WCM and other humanitarian initiatives. These estimates are the result of a globally consistent impact modelling framework using hazard, exposure and vulnerability information. The main focus are the hazards tropical cyclone and floods and their humanitarian impacts. The prototype of the tropical cyclone impact estimates works for exposed population and direct economic damage due to the sub hazard wind. It is currently being extended to take into account more sub hazards like precipitation, river floods and surge, and to represent different types of humanitarian impacts. The river flood impact estimates are currently under development and their skill and usability to inform decisions is assessed. We work collaboratively with the end user on the communication of these impact estimates to provide useful, useable and used access to authoritative information of the WMO family.