Society requires decision-relevant, evidence-based climate information to support mitigation strategies and adaptation choices. It needs this to address the challenges created by the pace of climate change and the emerging risks associated with climate extremes and hazards, which are being exacerbated by climate change. Required for this is actionable climate information that is based on new knowledge resulting from improved observations, better process understanding, and im proved, robust predictions and scenarios of climate change, produced at increasingly fine spatial resolutions and over a wide range of timescales. While there remain key scientific gaps, there are also new opportunities to advance scientific understanding through strategic partnerships. The World Climate Research Programme (WCRP) stands ready to lead the way in climate science to advance climate knowledge in support of society by addressing frontier scientific topics related to the coupled climate system, supported by strong global partnerships and addressing scientifically and technically complex challenges to improve resilience and preparedness, mitigation and adaptation.

To meet the challenges and opportunities of climate science over the next decade, WCRP has developed a new Strategic Plan. WCRP’s new scientific objectives are informed by the most pressing contemporary climate knowledge needs, as well as advancing the core science and capability needed to prepare for the challenges that society cannot yet foresee. These objectives are: (1) to advance fundamental understanding of processes, variations and changes in the climate system; (2) to predict the near-term evolution of the climate system; (3) to refine the ability to anticipate future pathways of climate system change; and (4) to support the development of theory and practice in the integration between natural and social sciences. Through these objectives, WCRP’s Core Projects will contribute to progress in the foundations of climate physics and biogeochemistry, in the predictive skill across all climate system components, and in the improvement of simulations of the past and projections of the future. To rapidly advance the field for key scientific frontiers, WCRP has established Lighthouse Activities which are designed to be ambitious and transdisciplinary, integrating across WCRP and collaborating with partners. These Lighthouse Activities will also setup new institutional frameworks that are needed to manage climate risk and meet society’s urgent need for robust and actionable climate information more effectively.

The talk will summarize WCRP’s new strategy and approaches to advance and steer climate science in support of society and will highlight the role of observations and models in this context. To understand relevant processes and mechanisms in every component of the climate system, and therefore to fully understand the Earth system, we require a diversity of observations and modelling approaches that span a range of complexity, a range of representations of processes, and a range of spatial resolutions, to resolve progress down to small scales. Respective coupled climate processes are fundamental to understanding variations in large scale circulation, the trajectories of regional and global sea level rise, and extreme events, all of which have severe regional and local impacts. Closing the energy, water, and carbon budgets of these systems is integral to observing, assessing, and simulating climate change and variability, regionally and globally. Frameworks for model evaluation and uncertainty estimation are required, as is collaboration across model development communities. The potential for seamless and unified simulation tools, adaptive architectures, statistical methods, and machine-based learning is yet to be fully tapped, and new approaches are needed for the integration of observations and models towards better representation of the Earth climate system.

Climate change and environmental degradation are an existential threat to Europe and the
world. To overcome these challenges, the European Green Deal will transform the EU into a
modern, resource-efficient and competitive economy.

From November 2020 to July 2021, Eurisy and DotSPACE hosted a webinar series bringing
together research, government and industry experts to talk about their innovative solutions
related to climate. Throughout the Space Opportunities for Climate Challenges series, various
examples have been showcased proving how satellite solutions can empower the green
transition. For example, satellite remote sensing can rapidly reveal where to reverse the loss
of biological diversity. Variables such as vegetation productivity or leaf cover can be measured
across continents from space and can help forest managers to implement more sustainable
ways of working. Furthermore, space is relevant for the management of maritime-related
matters, as it is for smart mobility and urban planning. When it comes to energy, space can
play a pivotal role in the decarbonisation of our economy. The daily space data stream also
provides insights about air and water quality, as well as irrigation systems, and even tourism.

Despite their strategic importance for sustainable economic, environmental and social
development, the uptake of satellite-based services remains limited. A lack of awareness of
the availability of satellite data and its potential interoperability with local data still poses a
major obstacle. Mitigating this issue will be crucial since impacts of climate change are
increasingly being felt at local level. Eurisy’s database of success stories is one of the
association’s primary tools to promote the use of satellite solutions for the benefit of
professional communities in numerous sectors on national, regional and local levels. By
sharing hands-on experience of public authorities, agencies, and SMEs, Eurisy aims to
eventually reach a critical mass of users and decision-makers tapping into the space data
stream to implement climate adaptation policies more easily.

Reanalyses form a key component of the suite of data products developed by the Copernicus Climate Change Service (C3S). ECMWF’s fifth generation global reanalysis (ERA5) has supported a growing user base, currently numbering more than 50 000 users. A preliminary extension of ERA5 back to 1950 was published in 2021. In addition to assimilating a comprehensive set of satellite data starting from the TOVS suite of instruments from 1979 onwards, ERA5 makes use of early infrared sounding data from VTPR, carried on NOAA-2 through-5 from 1972-1979. Reprocessed satellite data have played a role, alongside model and data assimilation developments, in delivering improved analyses relative to ERA5’s predecessor, ERA-Interim. Preparations are now underway for the next generation of reanalysis, ERA6, due to start in early 2024.
ERA6 will make use of several reprocessed satellite datasets produced by EUMETSAT as part of the first (2015-2021) and second (2021-2028) phases of the EU’s C3S programme. Plans currently include the production and assimilation of Fundamental Climate Data Records (FCDRs) for ATMS, MHS, MWHS-2, HIRS, SSM/T, SSMIS and European (MVIRI and SEVIRI) and Japanese geostationary satellite radiances. The first phase of the C3S programme has also delivered reprocessed datasets for several radio occultation missions (GRAS, COSMIC, GRACE and CHAMP) as well as Atmospheric Motion Vectors (AMVs) and scatterometer data (ASCAT). This element of C3S aims to produce comprehensive uncertainty analyses for the microwave sounders MSU, AMSU-A and ATMS. The impact of these new reprocessed datasets has been assessed in observing system experiments (OSEs) at ECMWF which show the new data generally exhibits lower biases, results in improved re-forecast quality and, in some cases, have an impact on the mean state estimate.
ERA6 will also make use of several recently rescued early (1970s) satellite datasets, including radiances from SI-1, SMMR, SSH, IRIS, SIRS, PMR, MRIR, NEMS, SCAMS, ESMR and SCR. Preparations to date have included the generation of improved radiative transfer models and evaluation of the quality of these radiances relative to ERA5 using analysis departures computed off-line.

Among the several effects of climate change, the rise of oceans level and occurrence of extreme meteorological events will inevitably result in coastal flooding episodes, temporarily or permanently eating away the coastline.
Rising to the challenge of mapping coastal flooding hazards and assessing their socioeconomic risks from satellite, the Littoscope project, supported by the French Space Agency in the framework of the international Space Climate Observatory (SCO), promotes the use of satellite data for information and decision-making related to the impact of rising oceans in coastal areas.
Littoscope is based on three pillars: a) mapping the coastal flood hazards using high-resolution optical satellite images and satellite altimetry data to estimate future flooded areas, b) assessing coastal flood risks based on local exposures and c) establishing an IT tool dedicated to local decision-makers.
The mapping of several scenarios of coastal flood hazards relies on Pleaides satellite images, from which is derived a high-resolution (0.5m) Digital Elevation Model (DEM). It takes into account the sea level trends estimated from satellite altimeter missions since 1993 (data from the Copernicus Climate Service) and decadal intensity of storm and tide surge from the global model MOG2D. The potential flooding water heights are first estimated through a bathtub approach comparing oceanic and terrestrial heights. A high-resolution hydrodynamic model is also applied to evaluate the capability of satellite-derived DEM to be used in climate modeling study or early warning tools to prevent coastal flooding risks.
The resulting risks of coastal flooding are estimated by crossing the hazard intensity with social, economic, natural and cultural exposures coming from a multi-sourcing (national, regional and local GIS datasets combined with land use information derived from the HR optical satellite image).
Two demonstration areas have been selected in France: the peninsula of Gâvres (4.5 km²) in Brittany and a broader area (102.4 km²) around the ponds near Palavas-les-Flots on the Mediterranean coast. The web platform has been co-designed with its future users among these territories to provide them with a comprehensive and easy-to-use tool.
This paper will exhibit the main outcomes of the Littoscope project and demonstrate how satellite assets can be used in combination with ocean models and socio-economics data to propose an highlighting tool about climate risks in the coastal areas.

Snow cover and Lake Ice cover have been both specified by the Global Observing System for Climate (GCOS) as part of the 50 essential climate variables (ECVs) to be monitored by satellite remote sensing. They are relevant input parameters for forecasts in the field of weather, hydrology and water management, therefore essential for assessing natural hazards such as floods, avalanches or river ice jams and managing associated risks.
Since July 2020, under European Environment Agency (EEA) delegation, the Copernicus Land Monitoring Service (CLMS) operationally produces and disseminates Pan-European High-Resolution Snow & Ice products (HR-S&I) at high spatial resolution (20 m x 20 m and 60 m x 60 m). They are derived from high-resolution optical and radar satellite data, from the Sentinel-2 and Sentinel-1 constellations respectively. Among near-real time (NRT) products, snow properties are described by two types of them.
Snow cover:
The Fractional Snow Cover (FSC) product provides the snow fraction at the Top Of Canopy (FSCTOC) and On Ground (FSCOG).
The daily cumulative Gap-filled Fractional Snow Cover (GFSC*) product provides a more complete FSC product, gap-filled both at spatial and temporal scales.
Snow state:
The Wet/Dry Snow (WDS) product differentiates the snow state within the snow mask defined by the FSCTOC information.
The SAR Wet Snow (SWS) product provides information on the wet snow extent in high-mountain areas.
Ice occurrences on the European hydrographic network are described by the River and Lake Ice Extent (RLIE) product. There are several RLIE products available, depending on their data source (either Sentinel-1, Sentinel-2 or a combination of both types of observations).

HR-S&I products are generated over the entire EEA38 (32 member countries and 6 cooperating countries) and the United Kingdom. The Sentinel-1 archive data from September 2016 is currently being processed while Sentinel-2 based products are already available from September 1, 2016 onwards to users.
This new Copernicus Service component has been developed and is currently operated by a consortium led by Magellium in partnership with Astri Polska, Cesbio, ENVEO, FMI and Météo-France, contracted by EEA as entrusted entity of DG-DEFIS (European Commission - Directorate General Defense Industry and Space) for this service.
The service is based on preexisting Research & Development algorithms and products conducted by CESBIO and supported by CNES for FSC products (MAJA(1) and LIS(2)), conducted by ENVEO and FMI teams for wet snow and GFSC products(3,4), and by Astri Polska developments for ice products. These algorithms have been turned into operational conditions, based on the WEkEO DIAS European cloud infrastructure.
Maximum efforts are made to provide NRT HR-S&I products within the ideal user requirement timeliness, ie 12 hours after the sensing date the maximum acceptable time lag for time-critical applications such as avalanche bulletins, weather forecasting, etc. This timeliness depends mainly on the date of publication of Sentinel-2/1 data on the Copernicus Service Hub by ESA, then once this data is available, NRT HR-S&I products are published within a maximum of 3 hours.

The presentation aims at describing in detail this new component of the CLMS.


(1) MAJA: the MACCS-ATCOR Joint Algorithm provides atmospheric correction and cloud-screening module to generate L2A products. It is a software developed by CNES and CESBIO, with contributions from DLR (https://zenodo.org/record/1209633#.XoGq7vE69hE)
(2) LIS: “Let It Snow” Snow detection algorithm: Gascoin, S., Grizonnet, M., Bouchet, M., Salgues, G., and Hagolle, O. (2018) Theia Snow collection: high resolution operational snow cover maps from Sentinel-2 and Landsat-8 data, Earth Syst. Sci. Data, https://doi.org/10.5194/essd-11-493-2019
(3) Nagler T. and H. Rott. 2000. Retrieval of wet snow by means of multitemporal SAR data. . IEEE Transactions on Geoscience Remote Sensing. vol. 38, no. 2, pp. 754–765, Mar. 2000.
(4) Nagler T., H. Rott, E. Ripper, G. Bippus, and M. Hetzenecker. 2016. Advancements for Snowmelt Monitoring by Means of Sentinel-1 SAR. Remote Sensing, 2016, 8(4), 348, DOI:10.3390/rs8040348.

The Copernicus Land Monitoring Service (CLMS) is one of the six core user driven services of Copernicus, the European flagship programme on Earth Observation and focuses on land monitoring, specifically at European scale, and also at global scale. The Land Service operationally produces a series of qualified bio-geophysical products on the condition and evolution of the land surface and on land cover and land use status and change. EU scale products are at high spatial resolution and global scale products are at mid to low spatial resolution with high time frequency; all are complemented by the constitution of long-term time series. The products are used to monitor the changes in dynamics of vegetation, the variability of the water cycle, the land energy budget, the terrestrial cryosphere and land cover changes. The service supports an increasing global user community for land resource monitoring, planning and also supports activities related to climate change monitoring and mitigation and adaptations initiatives. COP26 highlighted that, although the terrestrial biosphere feedbacks are a main issue, the impacting role of land cover changes and land management interventions still has a low level of confidence. GHG budgets over land are still ‘weak’ elements in climate models, hence detailed, correct and dynamic land data and information is more urgently required for climate related activities.
Space borne earth observations, however, directly support the development of bottom-up emission inventories for agriculture, forestry and other land uses (AFOLU). Such data also offer the capacity to monitor changes of land cover, land use and their biophysical condition that allow identification of options for creating resilience to destructive climate change impacts.
The need for continuous and quality controlled land data is recognized by IPCCC. The Copernicus Land Service global component therefor collaborates with the CEOS initiative in support of the UNFCCC Global Stocktake, scheduled for 2023.
We present details and applications of the CLMS products that are contributing to this and highlight compatibilities and differences with products from the Climate Service. We illustrate the value of integrated and derived datasets, such as water quality, land productivity and land degradation pressures. Furthermore, CLMS introduced processes that focus on user involvement, an important aspect in the MRV process (Measuring, reporting, verification), such as products linked to REDD+ for forest monitoring and GEOGLAM for agriculture and BIOPAMA for biodiversity.