ESA Earth Explorers

🧂🌶️ SMOS salinity could offer early indicator of El Niño 🌶️🧂 As the Pacific Ocean moves into an El Niño phase, scientists are monitoring changes in sea surface temperature, but also sea surface salinity. Sea surface salinity, the concentration of dissolved salts in the upper layer of the ocean, is much more than a measure of how salty the sea is. It responds rapidly to changes in rainfall, evaporation, river discharge and the melting and formation of sea ice. Salinity is both an important driver of ocean circulation and a tracer of the movement of water masses and surface currents. Together with temperature, salinity controls the density of seawater, triggering ocean currents that redistribute heat around the planet. Measurements from our Earth Explorer SMOS are revealing how freshwater and salt patterns shift across the Pacific as this year's El Niño develops – offering a potential new pathway for early detection. During normal, or neutral, conditions, strong trade winds trap a large layer of low-salinity surface water, known as the freshwater pool, in the far western Pacific. However, during El Niño, the easterly trade winds weaken or even reverse, removing the force that normally confines this warm western Pacific freshwater pool. The animation illustrates the movement of the freshwater pool during the 2023 El Niño and La Niña events, and the current emerging El Niño. "Salinity acts as a fingerprint of the water cycle," says SMOS Mission Manager, Klaus Scipal. “Where temperatures tell us how much heat the ocean contains, salinity gives us a first approximation where freshwater is entering or leaving the ocean. “Together, these measurements allow us to better understand the exchange of heat and water between the ocean and atmosphere, improving our ability to monitor and predict climate variability.” Read the story! 👇 🔗 https://lnkd.in/drqap4j8

🔥 EarthCARE’s view of severe wildfires in Spain 🔥 In the past week, wildfires raging just west of Madrid have displaced tens of thousands of people. These images below show data from EarthCARE, which captured the fires on 24 July 2026 as they burned very close to ESA’s deep space ground station in Cebreros. The facility was unharmed, but an area over 1500 square kilometres has burned in the region, which is over twice the size of the city of Madrid. This will have severe consequences for the livelihoods of many. Wildfires remain dangerous long after they have burnt out, with toxic wildfire smoke posing a long-term hazard to health. We can clearly see the areas affected by the fires, and the associated smoke plumes, in the multispectral imager (MSI) red-green-blue composite image. You can see the smoke plume travelling across the image over Madrid. We can also see EarthCARE measurements of aerosols over the region, via aerosol mass content data generated using the synergistic ACM-CAP product. The red area in the middle highlights the increase in aerosol concentration due to smoke near the site of the fires. ATL-EBD depolarisation values and extinction to backscatter ratio (aka the “lidar ratio”), shown in the second plot, help identify and classify aerosol presence. The EarthCARE satellite is capable of identifying and monitoring smoke plumes as they travel far from the source of wildfires, helping scientists understand their effects on Earth’s atmosphere. More on EarthCARE and where to access the data 🛰️https://lnkd.in/dyFT2r_7 More on EarthCARE’s ability to identify and trace wildfire smoke 🗺️https://lnkd.in/dMK2Bviu More on how EarthCARE identifies atmospheric aerosols 🔎https://lnkd.in/eQ8ZHxhs Thanks to Beniamino Abis, Lorenzo Di Ciolo, Alessandro Piro & Loredana Spezzi The MSI swath and ACM-CAP data here is displayed using Google Earth, 2026.

👐 The Biomass processor is going Open Source! 👐 This is a first of its kind for an ESA Earth Observation mission. We aim to promote scientific transparency, increase efficiency, open development to new communities, and prevent vendor or developer lock-in. As such, the Biomass Processor Suite operated in the ESA Payload Data Ground Segment (PDGS) has been made publicly available. 👉 https://github.com/BioPAL This enables everyone to access, work with and operate the latest official processor version while also contributing to its evolution following Open Source best practices. To support community involvement, a first open developer meeting was held in June to explain how scientists can contribute. The recording is now available, if you'd like to find out more! 👉 https://lnkd.in/ec75Qn5P

☄️ Marking the anniversary of Aeolus's trailblazing reentry ☄️ Our pioneering wind satellite Aeolus reentered Earth’s atmosphere on 28 July 2023 at around 21:00 CEST above Antarctica. Surpassing scientific expectations and exceeding its planned life in orbit, Aeolus was one of our most successful ESA Earth Observation missions. Its end will go down in history too, thanks to the ingenuity of ESA Operations, Engineering & Space Safety's mission control team who guided this remarkable satellite down through Earth’s atmosphere for a safe reentry. A series of complex manoeuvres lowered Aeolus’ orbit from an altitude of 320 km to just 120 km to reenter the atmosphere and burn up. Crucially, these manoeuvres – the first assisted reentry of its kind – positioned Aeolus so that any pieces that may not have burned up in the atmosphere would fall within a planned Atlantic ground track. Such a pioneering effort was not easy, and required immense teamwork and real-time problem solving to bring Aeolus home. You can relive the moments that had us on the edge of our seats throughout a whole week of intricate and intense days and nights, which we reported in a live blog. 🔗 https://lnkd.in/edNbvpP6 Today, satellite missions are designed according to regulations that require them to minimise the risk of causing damage on their return to Earth. This would typically be achieved by the majority of a satellite burning up on reentry or through a controlled reentry at the end of their life in orbit. However, when Aeolus was designed back in the late 1990s no such regulations were in place. So, after running out of fuel and without intervention, Aeolus would have reentered Earth’s atmosphere naturally within a few weeks from now – but with no control over where this would happen. Satellites and rocket parts fall back to Earth roughly once a week, and pieces that survive have only very rarely caused any damage, so the risk of Aeolus causing harm was always incredibly small. In fact, the chance of being struck by a piece of debris is three times less than being struck by a meteorite. Nevertheless, we went above and beyond for Aeolus and attempted a new way of assisting its reentry to make it even safer. More on the historic end to our trailblazing mission 👇 🔗 https://lnkd.in/eqNB27s9 🖼️2, Aeolus reentry at ESOC, Jürgen Mai 🖼️4, final images of Aeolus thanks to Fraunhofer FHR

‼️ Register by Friday 31 July for the Swarm Data Quality Workshop ‼️

⏳ Deadline approaching to register for the Biomass MAAP Hackathon ⌛ You've got until this Friday to register for the Biomass hackathon. ✍ Sign up by 31 July: https://lnkd.in/eNJ6iP77 ✅ Notifications of acceptance sent out early September 📅 12-16 October 🗺️ ESA Operations, Engineering & Space Safety, Darmstadt 🐍 Python familiarity required (the coding language mainly, but interesting snake facts are always welcome) What will we do at the hackathon? 🤝 Foster Global Collaboration ⏩ Evolve Biomass Processors ⏫ Enhance Data Accessibility 🧪 Innovate Analysis and Visualization Tools More info, and register 👇 🔗 https://lnkd.in/eNJ6iP77

🧊 CryoSat's incredible 16+ year ice record is now even better 🧊 Our record-breaking ice mission continues to deliver thanks to a new and improved record of ice sheet elevation and elevation change from CryoSat observations between 2010 and 2025. The data were validated against over 3 million ICESat-2 measurements, finding close agreement within a few centimetres (median differences in elevation rates of 0.01–0.02 m/yr, and 84% of assessed data agreeing to within 0.1 m/yr). Improving the accuracy of the historic global ice sheet record is critical for estimating future sea level rise, and provides a better benchmark for those studying and modelling ice loss. In a paper introducing this new dataset, a case study of Kangerlussuaq Glacier, Greenland (imaged below by Sentinels 1 and 2) provides a concrete example of improved monitoring of a rapidly changing glacier, resulting in a more consistent elevation-change time series with lower standard deviation. CryoSat's continuous, unbroken record spanning over 16 years and counting provides us with an invaluable set of data to digest and understand the magnitude and drivers of contemporary ice sheet mass loss during a period of rapid climate change. You can get your hands on it, too, thanks to Cryo-TEMPO! 💡 More on CryoSat data and where to find it: https://lnkd.in/eaYUbZRD 🗞️ Read the paper: https://lnkd.in/eA2tq5-8 📊 More on Cryo-TEMPO: https://lnkd.in/ec-a8znQ 🗞️ Thanks to UK Centre for Polar Observation and Modelling and Qi Huang, Mal McMillan and Karla Boxall (Lancaster Environment Centre). 🖼️1&3: Contain modified Copernicus Sentinel data (2026; 2021

CryoSat's continuous 16+ year record of global ice keeps on giving! 💅

🔥 EarthCARE’s view of ferocious Canadian wildfires 🔥 Wildfire season is intensifying across Canada, with recent events in Ontario and the Northwest Territories spreading smoke thousands of miles across North America. Although wildfires are a natural occurrence, particularly in Canada’s boreal forests where they contribute to ecosystem health and regeneration, they pose very real risks to infrastructure and air quality - and put lives at risk. Due to climate change the wildfire season is starting earlier and lasting longer, with 2023 marking Canada’s most destructive ever wildfire season having burnt 16.5 million hectares, and 2025 its second worst with over 8 million hectares burnt. The largest fires are currently burning in the Northwest Territories, where vast smoke plumes are being transported towards the Arctic Ocean and other parts of the country. Several wildfires can be seen burning near Fort Simpson in this EarthCARE acquisition from 16 July, together with their smoke plumes. Using data from EarthCARE’s multispectral imager (MSI) it is possible to highlight active wildfires and smoke plumes, while atmospheric lidar data from ATLID can be used to characterise emissions such as smoke. Additionally, data from the ATL_EBD_2A product show the vertical distribution of aerosol optical properties associated with the smoke plume (particle extinction, backscatter, and depolarisation), revealing the altitude, thickness, and optical structure of the transported smoke. 🔗 https://lnkd.in/eSEtpe3X An EarthCARE study of last year’s Canadian wildfires marked the first ever time a satellite had tracked the entire life cycle of wildfire smoke as it traversed the stratosphere from Canada to Europe, eventually mixing with tropospheric air over the Mediterranean and North Africa. 🔗https://lnkd.in/dMK2Bviu We will be keeping a close eye on the development of this year’s smoke plumes. 💡 For a comprehensive description of the target classification methodology and the interpretation of the classes shown, please refer to the EarthCARE Product Handbook 🔗https://lnkd.in/eDEruVqm ❓ For more facts on Canadian wildfires, read this fact sheet from the Canadian Climate Institute / Institut climatique du Canada 🔗https://lnkd.in/gT4E9x4M 🖼️ Fabulous work by Athanasia Nikolaou, Beniamino Abis, Lorenzo Di Ciolo, Alessandro Piro, Loredana Spezzi, Alex Hoffmann, et al. Data sources: ESA EarthCARE and Sentinel-3/OLCI Copernicus (2026), processed by ESA