D4.10 Lake Ice Service Expansion and Utilization Report

Version 1 19-June-2025 101003472 | Arctic Passion Deliverable 4.10 Lake Ice Service Expansion and Utilization Report This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 1 Dissemination level PU Work package 4 – Innovating user-driven Arctic EuroGEO Pilot Services Lead beneficiary 23 - Syke Lead author Kirsikka Heinilä (Syke) Contributors Sari Metsämäki (Syke) Timo Pyhälahti (Syke) Hanna Alasalmi (Syke) Status Project Coordinator accepted This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 2 Table of Contents 1. Introduction ......................................................................................................................................... 3 2. Service expansion ................................................................................................................................. 3 2.1. Integrated Data Sources for Ice Monitoring ................................................................................ 4 2.1.1. Earth Observation Data ........................................................................................................... 4 2.1.2. In-situ data and community-based monitoring ...................................................................... 7 2.2. Innovative User Tools and New Functionalities ........................................................................ 10 2.3. User-Driven Co-Design .............................................................................................................. 11 3. Service utilization ............................................................................................................................... 12 References .................................................................................................................................................. 16 This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 3 1. Introduction Lake Ice Service for Arctic Climate and Safety is one of the eight pilot services developed within the Horizon Europe Arctic PASSION project. The service provides near-real-time information on lake ice conditions in the Arctic, combining satellite observations, in-situ measurements, and community-based monitoring. The data are made openly accessible through the Tarkka web map platform developed by the Finnish Environment Institute (Syke). Since the publication of the Lake Ice Service Readiness Report in 2022 (Henilä et al, 2022), significant progress has been made to expand the service and improve its usability and societal relevance. The service has grown in data content, and in technical functionalities. New tools have been introduced to support community-based monitoring. This report outlines the main developments in the expansion and utilization of the Lake Ice Service. It describes how the service is being used by communities, authorities, scientists, citizens, and businesses, and highlights key outcomes such as improved safety on ice-covered lakes, increased awareness of climate impacts, and strengthened engagement with Indigenous and local knowledge holders. Lake ice is a key environmental variable in the Arctic. Its seasonal formation and breakup are closely linked to climate variability and change, with important implications for ecosystems, local livelihoods, transportation, and safety. As the Arctic warms rapidly, the need for timely and accessible lake ice information has grown, both for understanding climate impacts, and for supporting daily decision-making in northern communities. The Lake Ice Service continues to evolve through user-driven design, technological development, and close collaboration with communities. It demonstrates how integrated monitoring services can contribute to climate resilience and informed decision-making in Arctic regions. Arctic PASSION is an innovative pan-Arctic Observation and Monitoring action that rises to the challenges of climate change facing the people living and working in the Arctic, and to European society at large. The purpose of Arctic PASSION is co-creation and implementation of a coherent, integrated Arctic observing system. This will be achieved by refining its operability, improving and extending pan-Arctic scientific and community-based monitoring systems and services, streamlining the access and interoperability of Arctic Data systems, and crucially ensuring the economic viability and sustainability of the observing system for years to come. The Arctic PASSION project is described in more detail in the project website https://arcticpassion.eu/. 2. Service expansion Since the initial launch of the Lake Ice Service within the Arctic PASSION framework, the service has undergone substantial expansion in both its technical scope and geographic reach. The developments have aimed to enhance the usability, relevance, and accessibility of lake ice information for Arctic users and anyone interested in the Arctic. The service integrates multiple complementary data sources, each contributing to a more complete and accurate understanding of ice conditions. In the following, the data sources and functionalities are described in more detail. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 4 2.1. Integrated Data Sources for Ice Monitoring 2.1.1. Earth Observation Data The Lake Ice Service integrates multiple satellite-based data sources summarized in Table 1. Currently, the service utilizes Near-Real-Time Lake Ice products from Copernicus Land Monitoring Service (CLMS), including i) 250m resolution daily Lake Ice Extent (LIE) product for the Continental Europe (CEURO LIE) (Figure 1) and ii) 500m resolution daily LIE Product for the Northern Hemisphere (LIE-NH) (Figure 2). The CEURO LIE is based on VIIRS (Visible Infrared Imaging Radiometer Suite) data from the NOAA-20 satellite and has been available since July 2024. It is a continuation of the earlier LIE 250 m product for Northern Europe, which was based on MODIS (Moderate Resolution Imaging Spectroradiometer) data from the Terra satellite. The Northern Europe LIE 250 m product is available in the service for the period from March 2017 to June 2024. The LIE-NH product is based on data from the Sentinel-3 SLSTR (Sea and Land Surface Temperature Radiometer) and has been available since April 2021. More information on the CEURO LIE, Baltic LIE, and LIE-NH products is available on the Copernicus Land Monitoring Service website Water Bodies — Copernicus Land Monitoring Service. Table 1. Current and future satellite data sources and interfaces in Tarkka for Lake ice service. Dataset Origin Interface type Current raster data CLMS Lake Ice Extent Continental Europe (250m) Syke open data (GeoServer)*, CGLS WMS, ftp CLMSS Lake Ice Extent Northern Europe (250m) Syke open data (GeoServer)*, CGLS WMS, ftp CLMS Lake Ice Extent Northern Hemisphere (500m) Syke open data (GeoServer)*, CGLS WMS, ftp Sentinel-2 true-colour data (10m) Sentinel hub service with Syke modifications WMS Sentinel-3 true-colour data (300m) Sentinel hub service with Syke modifications WMS Landsat-8/9 true-colour data (30m) Syke’s open data (GeoServer)* WMS Sentinel-3 SLSTR based Water Surface Temperature (1km) Syke’s open data (GeoServer)* WMS Landsat-8/9 based Water Surface Temperature (10m) Syke’s open data (GeoServer)* WMS Sentinel-1 SAR data (20m) Sentinel hub service with Syke modifications WMS Coming raster data CLMS Water Ice Cover Europe (20m) in 2026 Copernicus Land Monitoring Service (CLMS) WMS This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 5 Figure 1. Copernicus Land Monitoring Service Lake Ice Extent data for Continental Europe (CEURO LIE) in 250 m resolution and Landsat OLI 30 m resolution true-colour image (background) for Lake Inari, Finland, on 23 May 2025. USGS/NASA Landsat Program, Syke, Copernicus Service information, funded by EU. Figure 2. Copernicus Global Land Lake Ice Extent product for Northern Hemisphere (LIE-NH) in 500 m resolution on 23 March 2025. The Lake Ice Service also provides information on the water surface temperature (Figure 3. Landsat-8/9 TIRS–based water surface temperature (foreground) and Sentinel-2 MSI true-colour image (background) for Lake Inari, Finland, on 12 October 2024. Water surface temperature data provide valuable information, for example, on the potential timing of lake freeze-up.Figure 3). These datasets are based on daily 1 km resolution Sentinel-3 SLSTR data, as well as on higher-resolution, but temporally sparse 30 m data from the Landsat-8/9 TIRS (Thermal Infra-Red Sensor). Water surface temperature data offer valuable insights, for example, into the potential timing of lake freeze-up. As with optical data, cloud cover can obstruct the retrieval of temperature information. To overcome the limitation of clouds and polar night, Sentinel-1 Synthetic Aperture Radar (SAR) data at 20 m resolution have been integrated into the Lake Ice Service (Figure 4), as radar can penetrate clouds and operate during darkness. However, interpreting ice conditions from SAR imagery is not always as straightforward as with optical instruments. Despite this, SAR has been specifically requested by users, particularly those involved in hydropower management and flood prevention, due to its ability to provide observations in the challenging Arctic conditions. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 6 Figure 3. Landsat-8/9 TIRS–based water surface temperature (foreground) and Sentinel-2 MSI true-colour image (background) for Lake Inari, Finland, on 12 October 2024. Water surface temperature data provide valuable information, for example, on the potential timing of lake freeze-up. Contains modified Copernicus Sentinel-2 data, Syke, USGS/NASA Landsat Program, Syke. Figure 4. Sentinel-1 SAR data is added to the Lake Ice Service with a several visualization options. Utilizing the swipe tool, it shows that the Sentinel-2 MSI true-colour image is cloud-covered (right side of the image), while the radar image provides observations of the lake despite the cloud cover. Lake Inari, Finland, on 24 May 2024. (Contains modified Copernicus Sentinel-1 data, Syke, Contains modified Copernicus Sentinel-2 data, Syke) The Lake Ice Service module visualizes high-resolution satellite true-colour images using Sentinel-2 MSI (Multispectral Instrument) with 10 m spatial resolution and Landsat-8 OLI (Operational Land Imager) with 30 m resolution. The temporal resolution of these datasets is typically a few times per week per sensor. In addition, daily Sentinel-3 OLCI (Ocean and Land Colour Instrument) true-colour images with 300 m This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 7 resolution are available through the service, providing a more extensive view of the area for the user’s convenience. All true-colour images can be viewed with different visualization options, depending on environmental conditions and user needs. Available themes include snow cover, near-infrared, and false-colour composites. In addition to CLMS medium-resolution LIE-products, the suitability of the Copernicus high-resolution River and Lake Ice Extent (RLIE) products as a data source for the Lake Ice Service have been investigated (River and Lake Ice Extent 2016-2025 (raster 20 m), Europe, daily — Copernicus Land Monitoring Service). The current version has occasional difficulties in ice classification and misclassifications are more frequent than with the CLMS medium-resolution products. Thus, it is decided that RLIE product will not be included to the Lake Ice Service until their quality is improved. However, the product is currently under renewal. Syke will validate the upcoming Copernicus high-resolution Water Ice Cover (WIC) -product in 2025−2026, which is set to replace the current RLIE product in CLMS portfolio in autumn 2025. If the quality meets the required standards, the high-resolution WIC product will be integrated into the Lake Ice Service. 2.1.2. In-situ data and community-based monitoring Syke has developed platforms to collect and store community-based observations. Community-based monitoring enables residents and others who travel or work on ice-covered lakes to contribute real-time, location-specific information that enhances satellite interpretation and increases situational awareness. To disseminate the Lake Ice Service and collaborate with users, we are linking with our community-based monitoring network, Arctic Monitoring and Assessment Programme (AMAP) and other user groups. Examples of activities combining Earth Observation and community-based monitoring are demonstrated in Figure 5. Reported ice observations from satellite images allow users to annotate the imagery with information about ice conditions—such as cracks in the ice—to warn others and contribute to a shared database of local knowledge. A mobile application Iceobs.app, also connected with the Lake Ice Service, allows users to submit ice observations from the field in just a few seconds even without internet access addressing the connectivity challenges of Arctic regions. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 8 Figure 5: Melted area caused by river current in the Lokka reservoir, Finland, on 10 May 2025. Reported ice observations based on satellite imagery allow users to annotate images with information about ice conditions, such as cracks, helping to warn others and contribute to a shared database of local knowledge. (Contains modified Copernicus Sentinel-2 data, Syke (2025). Ice observations from the Finnish governmental observation network are also visible in the service. Syke maintains an extensive dataset of official in-situ ice phenology observations, with records dating back to the 18th century. The measurements include the thickness of the congelation ice. These long-term datasets enable the study of changes in lake ice climatology. Figure 7 illustrates both field-based and satellite-derived observations in the Lake Ice Service. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 15 Figure 11. Winter fishing is a long-standing tradition in the Arctic. Reference: Riku Lumiaro, Syke´s Image bank. implementation of the Lake Ice Service under Arctic PASSION has demonstrated the value of combining satellite data, in-situ measurements, and local knowledge into a single, accessible platform. The service has grown from a regional pilot into a scalable, pan-Arctic tool that supports safety, decision-making, and climate resilience in northern communities. Through continuous collaboration with users, technical innovation, and community engagement, the Lake Ice Service has become more than just a data platform, it is a co-produced service grounded in Arctic realities. As this phase of work concludes, the foundation has been laid for further expansion and longterm impact. As the Arctic continues to warm, the demand for accurate, localized, and timely lake ice information will only increase. The Lake Ice Service will continue to serve Arctic communities and stakeholders beyond the project’s lifetime evolving with their needs and strengthening the shared knowledge base for a safer and more informed Arctic future. Link to the service: Tarkka - Lake Ice Service This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 101003472 Arctic PASSION | Deliverable 4.10 | 19-June-25 16 References Heinilä, K.; Metsämäki, S.; Pyhälahti, T.; Alasalmi, H.; and Koponen, S. (2022). D4.1 - Lake Ice Service Readiness Report. Zenodo. https://doi.org/10.5281/zenodo.14956525 Johnson, N.; Behe, C.; Danielsen, F.; Krümmel, E.M.; Nickels, S. and Pulsifer, P.L. (2016) Community-Based Monitoring and Indigenous Knowledge in a Changing Arctic: A Review for the Sustaining Arctic Observing Networks. Final report to Sustaining Arctic Observing Networks. Ottawa, Canada: Inuit Circumpolar Council, 65pp. DOI: http://dx.doi.org/10.25607/OBP-822