Identifying needs and opportunities for Earth observations in anticipatory action

It is said that an ounce of prevention is worth a pound of cure. But while anticipatory action promises to reduce disruptions to people’s lives and livelihoods, opportunities to implement anticipatory action may not always be easy to identify in practice. Even when a potential opportunity is identified, setting up the rigorous protocols required for adoption can be complicated.

Space-based and remotely sensed technologies can help to simplify, justify or improve anticipatory action programmes – and may even provide opportunities for additional programmes based on triggers that have not yet been considered. To investigate these potential benefits, the Anticipation Hub’s working group on Earth Observations for Anticipatory Action (EO4AA) conducted a needs assessment to identify opportunities and gaps for Earth observations across the cycle of anticipatory action.

Earth observation has been used extensively for anticipatory action, for example to harness precipitation observations and numerical weather prediction products. These are often used as inputs to hydrologic models that provide triggers based on streamflow or river height; examples include the Red Cross Red Crescent’s early action protocols (EAPs) for floods in Bangladesh and Zambia. Moreover, Earth observation data provides a basis for the wind-speed predictions used for cyclone triggers, and temperature and precipitation predictions in triggers for drought or those related to El Niño.

Anticipatory action comprises three main phases: (1) EAP development; (2) EAP activation and implementation; and (3) EAP evaluation. Earth observation data provides significant benefits throughout the EAP process, from trigger development and evaluation to activation, real-time monitoring, and monitoring the success of anticipatory action.

• In the development phase (1), there is usually a risk assessment which uses hazard data (e.g., the probability of a hazard occurring in a region), exposure (e.g., number of houses/households that will potentially be affected) and social vulnerability (e.g., poverty ratio). A trigger is developed based on historical information about hazard characteristics and related impacts.
• Early actions are also defined in phase I. This is usually done with the support of qualitative data, for example from focus group discussions with the target population, or consultations with stakeholders such as government entities. 
• To identify the threshold at which the impact is deemed critical, and the EAP is activated (phase 2), this impact level needs to be defined based on past impacts and/or damage assessments, and then correlated with the respective hazard severity. For example, the Philippine Red Cross considers the impacts of typhoons as ‘critical’ when the forecast impact of wind speed on infrastructure results in more than 10 per cent of houses being destroyed in at least three municipalities.

In the context of specifically triggering anticipatory actions (Phase II), the primary function of Earth observation data may be to track weather, but many of the fundamental requirements to set up an effective EAP can benefit substantially from Earth observation. EAPs are only as good as the risk assessments on which they are based. Risk assessments most commonly integrate risk models, catastrophe (CAT) modelling and loss-estimation programmes that offer a well-established framework for assessing risk. The modelling paradigm provides a new set of tools with which to improve risk analysis within the EAP framework, and the models can use Earth observation data to identify populations at risk, establish the distribution of buildings, improve the estimation of the hazard, and validate results. The risk assessments used in the development process then provide the basis for real-time estimates of potential impacts to inform activations. During the evaluation phase (phase 3), Earth observation can be used to understand how communities rebuild, and potentially to characterize whether access to anticipatory action funding increased community resilience.

The EO4AA working group has identified several potential opportunities for integrating Earth observation into the entire EAP process, from trigger development to monitoring and evaluation- The group has also explored its potential application to new hazards, the monitoring of cascading effects, and the integration of citizen science. The report reflecting the needs assessment and the identification of opportunities for improved future integration of Earth observations across the EAP cycle will be released in April 2022.