From Space: Satellites Show Fires, Drought and Heatwaves

Satellites have fundamentally changed the understanding and management of natural hazards. In addition to high‑resolution images, they provide measurements that help emergency responders, researchers and authorities. The European Space Agency provides continuously updated image series that document heat extremes, drought and fires and place them in the context of climate change.

Detecting fires from space

Thermal infrared sensors record heat signals. When vegetation burns, shortwave infrared radiation increases markedly; satellites detect these hotspots almost in real time. This makes it possible to locate ignition points, track fire spread and estimate intensity using indicators such as Fire Radiative Power (FRP). Multispectral data complement the analyses: burned areas have characteristic spectral signatures and can be mapped automatically. Such burn‑area maps are important for emissions estimates and reforestation planning.

Making smoke and air quality visible

Satellite instruments measure aerosols and trace gases produced by fires. From these data, maps of smoke concentration and transport are generated and combined with meteorological wind fields. These products support health warnings because fine particles (PM2.5) can be transported over long distances and affect the respiratory system.

Measuring drought: more than dry soil

Drought appears in several indicators. Vegetation indices like the NDVI capture greenness and therefore plant stress. Land surface temperatures provide clues about heat and evapotranspiration. Microwave and radar techniques measure soil moisture independently of clouds. Gravimetry missions and in‑situ observations complete the picture by detecting changes in groundwater and long‑term water losses. Together, these data allow assessment of agricultural risks, crop shortfalls and increasing vegetation fire risk.

Heat extremes in context

Satellite maps show urban heat islands, temperature contrasts between vegetation and sealed surfaces, and large‑scale heatwaves. Prolonged heat increases evaporation, warms the soil and strengthens the feedback between heat and drought. Long‑term time series make it possible to quantify trends and study the clustering of extreme events over decades, including for attribution studies.

Data fusion and models

The value of individual products increases through integration. In data assimilation, satellite data feed into weather and land‑surface models. This produces more accurate forecasts of fire spread, firefighting needs and water availability. Applications range from priority maps for responders to indicators of irrigation needs and regional warning levels. Remote sensing data also feed estimates of CO2 and black carbon emissions for climate and air quality inventories.

Limitations and uncertainties

Optical sensors are limited by dense smoke or clouds. Radar and microwave sensors therefore provide important complements because they measure independently of visibility. Temporal resolution depends on orbits and sensors; rapid developments require multiple data sources, including geostationary satellites. Validation with ground measurements remains central to verify quantities such as emissions or soil moisture.

From monitoring to prevention

Long‑term data support planning decisions. Maps of recurring drought risk, ecosystem vulnerability and urban heat islands enable targeted adaptation measures: optimized irrigation strategies, reforestation, adapted building and open‑space planning, and heat action plans. Early‑warning systems for fires reduce response times. At the same time, satellite data form a basis for accounting emissions from fires.

Images as an impetus

Updated satellite images visualize changes, support risk communication and provide case studies for analysis. They show that technological observation and local action belong together: the view from space makes problems visible, while solutions are implemented on the ground.