The Role of Satellite EO

Satellite EO provides a unique capability to monitor environmental conditions relevant to adaptation and resilience consistently across national boundaries and over long time periods. Many of the variables that drive or identify hazards can be measured directly from space, enabling systematic observation of the Earth system at different scales.

Because satellite observations are collected using consistent measurement techniques across large geographic areas, they also enable the development of globally comparable environmental indicators. The key features of satellite EO in this context are:

As of 2026, around 150 satellite missions are in active service provided by CEOS space agencies and many of these have free and open data archives for exploitation of their data. These datasets provide the basis for consistent and spatially comprehensive information that underpins scientific understanding of change and supports decision-making. This availability, continuity, and coverage of EO data is not only essential for monitoring resilience, but enhances the resilience of this data as well.

When integrated with models, ground observations and socio-economic data, satellite EO can be a powerful tool for informing adaptation and resilience decisions. Satellite EO supports multiple stages of adaptation and resilience. EO data contribute strongly to the risk assessment stage, where hazards, environmental trends, and exposure patterns must be understood. They also play an important role in monitoring and evaluation, where long-term environmental observations allow changes in climate conditions and ecosystem responses to be tracked over time. Planning and implementation decisions typically involve additional socio-economic and governance factors that cannot be observed directly from space, nevertheless satellite data provide an essential environmental evidence base that informs these decisions.

Figure 3-1 illustrates how EO data can support each stage of the adaptation cycle.

The relative contribution varies across stages: EO is particularly influential in the risk assessment and monitoring and evaluation phases, where environmental observations are fundamental to understanding hazards and tracking environmental change. In the planning and implementation stages, EO plays an important role by informing decision-support tools, spatial analysis, and early warning systems.

The first stage of the adaptation cycle focuses on understanding changing risks by analysing hazards, exposure, and vulnerability. Satellite observations provide key inputs to this process by enabling systematic monitoring of environmental variables relevant to hazards. Atmospheric and ocean observations support the monitoring of phenomena such as temperature extremes, precipitation patterns, tropical cyclones, and sea-level rise, while land surface observations provide information on soil moisture, vegetation health, snow cover, and water availability.

These datasets allow scientists and decision-makers to identify emerging risks and to assess how environmental conditions are evolving over time. For example, long-term satellite records of sea-level rise derived from radar altimetry missions provide essential information for coastal risk assessments, while satellite soil moisture observations contribute to drought monitoring systems used, for example, in agricultural risk management. Products derived from missions such as NASA’s Soil Moisture Active Passive (SMAP) satellite and ESA’s Soil Moisture and Ocean Salinity (SMOS) mission provide near-global information on soil moisture conditions. These datasets are used by organisations including the Famine Early Warning Systems Network (FEWS NET), Group on Earth Observations Global Agricultural Monitoring (GEOGLAM) Crop Monitor, and national agricultural agencies to identify emerging drought conditions and anticipate impacts on crop production and food security. By providing spatially comprehensive observations across national territories and regions, EO data enable consistent mapping of hazard exposure and environmental change.

During the planning stage, governments and institutions translate risk assessments into strategies, policies, and investment plans. Satellite EO contributes to this stage primarily through spatial analysis and environmental monitoring, helping planners understand where adaptation measures may be most effective.

High-resolution satellite imagery allows planners to identify settlements, infrastructure networks, and agricultural areas located in hazard-prone zones such as floodplains or low-lying coastal regions. EO-derived land cover and land use datasets also help assess ecosystem conditions and identify areas where nature-based solutions – such as wetland restoration or improved land management – may reduce risk.

Satellite data are therefore frequently used within geospatial planning tools, environmental models, and climate risk maps that support national and regional adaptation planning processes, including the development of NAPs.

For coastal regions, one example is the use of satellite altimetry missions (including TOPEX/Poseidon, Jason-1/2/3, and the recent Sentinel-6 Michael Freilich mission) to produce multi-decadal records of global sea-level change to a high precision. These datasets (a long-term cooperation between the CEOS agencies CNES, ESA, EUMETSAT, NASA, and NOAA) have become a key evidence base for coastal adaptation planning, helping governments and researchers assess long-term trends in sea-level rise and evaluate future flood risks in vulnerable coastal zones. For example, coastal monitoring programmes in countries such as the Netherlands, Bangladesh, and Australia incorporate satellite altimetry data alongside tide-gauge observations to inform flood risk assessments and coastal protection strategies. The Netherlands Delta Programme explained in Section 2 integrates satellite altimetry observations with tide-gauge records and hydrodynamic modelling in their Sea Level Rise Knowledge Programme to assess long-term sea-level trends and future coastal flood risk and to guide long-term investment in flood defences, spatial planning, and coastal management.

Although implementation decisions often depend on institutional, financial, and governance factors, EO data can support the delivery of adaptation measures in several ways. Satellite observations contribute to operational monitoring systems, including flood monitoring, drought early warning, and wildfire detection services. These systems allow authorities to anticipate emerging hazards and respond more effectively. Radar satellites, for example, can map flood extent during extreme rainfall events even under cloud cover, while meteorological satellites continuously track the development and movement of severe weather systems. Such capabilities form an important component of early warning systems and disaster preparedness efforts.

The final stage of the adaptation cycle involves assessing whether adaptation and resilience measures are effective and how risks are evolving over time. Satellite observations are particularly valuable in this stage because they can be prepared in such a way that they provide long-term, consistent environmental records that allow changes in hazard drivers to be tracked over decades.

An important challenge in the monitoring and evaluation of adaptation actions is attribution – determining whether observed changes in environmental or societal outcomes can be linked to specific adaptation measures rather than to broader climatic or socio-economic trends. For many Essential Climate Variables (see below), satellite observations extend back decades, allowing trends in surface temperature, vegetation condition, water availability, and sea level to be analysed over long time periods. In many cases, adaptation actions aim to reduce exposure to hazards or mitigate environmental impacts, such as reducing flood risk, improving water management, or lowering heat stress in urban environments. To determine whether these measures are successful, environmental and societal conditions are compared before and after the intervention while accounting for broader variability. Attribution of adaptation outcomes rarely relies on satellite data alone and involves in-situ measurements, socio-economic data, and modelling approaches in order to interpret observed changes and identify their underlying causes. For example, research examining the impacts of heat stress on human health may integrate satellite observations of land surface temperature and aerosol concentrations with ground-based measurements and demographic data to analyse relationships between environmental conditions and health outcomes. This integrated approach strengthens analysis and highlights the role of EO in adaptation and resilience decision-making.

Attribution of adaptation outcomes rarely relies on satellite data alone and involves in-situ measurements, socio-economic data, and modelling approaches in order to interpret observed changes and identify their underlying causes. For example, research examining the impacts of heat stress on human health may integrate satellite observations of land surface temperature and aerosol concentrations with ground-based measurements and demographic data to analyse relationships between environmental conditions and health outcomes. Such integrated approaches allow the assessment of both risk driver changes and the effects of adaptation measures.

One framework for identifying key observables is the Essential Climate Variables (ECVs) defined by the Global Climate Observing System (GCOS). These variables represent key components of the climate system required to inform all stages of the risk framework. Approximately two-thirds of the 55 ECVs can be observed using satellite instruments, including variables such as surface temperature, precipitation, sea level, soil moisture, vegetation condition, and land cover. These datasets provide consistent and spatially comprehensive information that underpins scientific understanding of our planet.

These observations can support the development of environmental indicators related to reducing risk and strengthening resilience. For example, long-term satellite measurements of vegetation productivity can reveal trends in ecosystem health, while observations of surface water extent can track changes in water availability or flood frequency. Unlike mitigation, where greenhouse gas emissions provide a clear quantitative metric, adaptation outcomes are often context-specific and influenced by multiple environmental and socio-economic factors. As a result, identifying robust indicators that can support national and global assessments of adaptation and resilience is a clear opportunity for EO observables.

Work is underway within the Global Goal on Adaptation (GGA) to identify indicators that can help track global progress. Many of the proposed indicators relate to environmental conditions linked to hazards and ecosystem health, including water availability, land degradation, coastal change, and agricultural productivity. Satellite EO datasets are increasingly recognised as a valuable source of information for monitoring such indicators, complementing national monitoring systems and helping to establish globally consistent reference points for environmental change. The development of these indicators presents an important opportunity to incorporate EO data and expertise into adaptation monitoring frameworks, where they can be combined with in-situ observations, socio-economic data, and modelling approaches to create a comprehensive understanding of adaptation outcomes. Incorporating EO-based indicators early in the process helps ensure that globally comparable datasets are available to all countries and reduces the difficulty of introducing EO methodologies at later stages.

Satellite EO has the potential to make an important contribution to resilience and adaptation efforts by providing consistent environmental datasets that can support indicator development. Observations of variables such as surface temperature, soil moisture, vegetation productivity, land cover change, surface water extent, and sea level can provide measurable indicators of environmental conditions that influence hazards and ecosystem responses. Because these datasets are generated using consistent measurement approaches across regions and time periods, they offer a foundation for indicators that are comparable across countries and regions.