Tracking how Earth's climate is changing requires data that are consistent, long-term, and freely accessible. The European Space Agency's Climate Change Initiative (ESA CCI) – a programme dedicated to generating high-quality satellite-derived records of Essential Climate Variables (ECVs) – has recently released six updated datasets focussed on forests, wildfire, lakes, vegetation, and atmospheric composition. Each release extends or improves an existing record, giving researchers, modellers, and policymakers sharper tools to understand a changing planet. Advancing such records is the core purpose of ESA’s CCI: to undertake pre-operational research and development that improves retrieval algorithms and processing chains, merging observations from multiple satellite missions into long-term climate data records for ECVs. The resulting records strengthen climate science, provide key evidence for assessments by the Intergovernmental Panel on Climate Change (IPCC), and help improve the models used to analyse and predict future change. Beyond research, the records also underpin downstream applications, with many datasets transferred into operational climate services such as the Copernicus Climate Change Service (C3S). All datasets are available via the ESA CCI Open Data Portal.
1. Forests: two decades of carbon storage, now in sharper detail
The ESA CCI Biomass project has released version 7.0 of its global forest above-ground biomass dataset, delivering a more consistent and reliable record of the carbon stored in the world's forests over two decades. The updated dataset now covers 2005–2012 and 2015–2024, with new annual maps added for 2005, 2006, 2008, 2009, 2011, 2012, 2023, and 2024. The gap in 2013 and 2014 reflects the transition between satellite missions: the radar satellite used to collect data for 2005–2012 was decommissioned in 2012, with new missions coming online from 2015. Maps are derived from a combination of radar and lidar Earth observation data, with a cost function applied to limit biases between the two time periods. Multi-scale aggregated data layers are available at 1 km, 10 km, 25 km, and 50 km resolution. A new Python tool, freely available alongside the data, allows users to compute above-ground biomass change maps for any pair of annual maps. Access the dataset.
2. Fire: a consistent burned area record from 2003 to 2024
The ESA CCI Fire project team has delivered the Harmonised Medium Resolution Burned Area product, version 6.0 – a complete monthly global time series of burned area from 2003 to 2024. It was achieved by harmonising two previously separate records: an older dataset (FireCCI51) and a newer one (MRBA60). The challenge was significant: the newer record uses improved detection methods and identifies over 20% more burned area than the older one, meaning a simple merge would have introduced an artificial jump and distorted long-term trends. The solution uses a machine-learning model trained where the two records overlap, then applied retrospectively to reconstruct 2003–2018 in line with the newer detection behaviour. The result is a dataset that provides a consistent record across the full time series. Access the dataset.
3. Lakes: seven variables, over 2,000 lakes, three decades of data
A major update of the Lakes Essential Climate Variable products offers an enhanced, globally consistent view of lakes as key indicators of climate and environmental change. Version 3.0 of the Lakes_cci dataset features longer time series, greater spatial coverage, and improved algorithms for certain variables – and introduces Lake Storage Change as a new variable for the first time. Developed using observations from 35 satellite sensors, this release covers over 2,000 lakes from 1992 to 2023 across seven variables: Lake Water Level, Lake Water Extent, Lake Water-Leaving Reflectance, Lake Surface Water Temperature, Lake Ice Cover, Lake Ice Thickness, and Lake Storage Change. Together, these variables provide more complete and actionable information to better understand how lakes are responding to a warming world. Access the dataset.
4. Vegetation: leaf area and light absorption across a north-south transect
A new multi-sensor, jointly retrieved dataset of effective Leaf Area Index (LAI) and fraction of Absorbed Photosynthetically Active Radiation (fAPAR) has been released by the ESA CCI. LAI measures the total area of leaves per unit of ground surface, while fAPAR captures how much of the available sunlight plants actually absorb for photosynthesis – both are critical indicators of vegetation health and productivity. This first release is a pilot dataset, covering a north-south transect from Finland to South Africa and the full Mediterranean area from 2000 to 2020 at 1 km spatial resolution – a targeted starting point before the record is extended to global coverage. Access the dataset.
5. Atmospheric composition: two new records from Copernicus Sentinel-5P
Two datasets tracking atmospheric trace gases have been released using observations from the Tropospheric Monitoring Instrument (TROPOMI) aboard Copernicus Sentinel-5P.
The first provides a record of formaldehyde (HCHO) – a short-lived gas that forms when methane and organic compounds react in the atmosphere. Tracking this gas from space provide valuable information for scientists working to understand pollution sources, vegetation emissions, and the chemistry driving ozone and aerosol formation. Generated by the Royal Belgian Institute for Space Aeronomy under ESA's Precursors for Aerosols and Ozone project, version 2.0 incorporates reprocessed air mass factors based on an updated albedo climatology and the Copernicus Atmosphere Monitoring Service Reanalysis Model, as well as refined background correction and quality values. The dataset provides monthly gridded measurements from May 2018 to December 2024. Access the dataset.
The second record provides monthly mean concentrations of tropospheric nitrogen dioxide (NO2) – a pollutant primarily released by traffic, industry, and power plants, which contributes to climate change through its role in forming ozone and aerosol – allowing scientists to monitor air pollution hotspots, assess emission trends, and understand the chemistry driving ozone formation. Produced by the Royal Netherlands Meteorological Institute under the same project, the dataset covers May 2018 to December 2021 and is ready for use in model evaluation, trend analysis, and emission studies. Access the dataset.