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West Africa, already highly influenced by the negative effects of climate change, is additionally characterized by rapid population growth, endemic poverty, and insecurity. This is affecting the natural capital of its ecosystems and the services they provide. Natural capital accounting (NCA) provides the fundamental evidence base required for informing economics and environmental decisions, thus strengthening the conservation and management of natural resources. The objective of this study is to showcase the development and evaluation of a semi-automated NCA platform (Sys4ENCA) designed to support decision making in the context of protected areas management in a multi-level example in western Africa. The accounting results highlight that simulations at the broader scale using national public data show that the natural capital of ecosystems in western Africa depends strongly on the mean climate and its variability. Evaluating regional datasets, the simulation with the platform shows that pressure on land in combination with weak governance reduces the capability of the ecosystem to deliver the required services in a sustainable manner, i.e., in the eastern part of the Bafing-Falémé landscape, where mining and intensive agriculture are fueling loss of natural capital. The results of Tier-3 accounting using local datasets enhanced the spatial variability and highlighted additional hotspots of degradation compared to the regional results, i.e., the prospective construction of a hydro-electricity dam (Koukoutamba) in the southern part of the Moyen-Bafing National Park located in the Bafing-Falémé landscape. The Sys4ENCA platform, combined with a multi-level approach, showed itself to be a valuable tool to facilitate protected area management as it provides not only consolidated information at a local scale but also the broader context and external pressures, i.e., climate change and demand for land. Given its automatized nature, the platform reduces human errors and increases the efficiency, speed, and harmonisation of computation over long timeframes and spatial scales.

Annual global land cover maps (GLC) are being provided by several operational monitoring efforts. However, map validation is lagging, in the sense that the annual land cover maps are often not validated. Concurrently, users such as the climate and land management community require information on the temporal consistency of multi-date GLC maps and stability in their accuracy. In this study, we propose a framework for operational validation of annual global land cover maps using efficient means for updating validation datasets that allow timely map validation according to recommendations in the CEOS Stage-4 validation guidelines. The framework includes a regular update of a validation dataset and continuous map validation. For the regular update of a validation dataset, a partial revision of the validation dataset based on random and targeted rechecking (areas with a high probability of change) is proposed followed by additional validation data collection. For continuous map validation, an accuracy assessment of each map release is proposed including an assessment of stability in map accuracy addressing the user needs on the temporal consistency information of GLC map and map quality. This validation approach was applied to the validation of the Copernicus Global Land Service GLC product (CGLS-LC100). The CGLS-LC100 global validation dataset was updated from 2015 to 2019. The update was done through a partial revision of the validation dataset and an additional collection of sample validation sites. From the global validation dataset, a total of 40% (10% for each update year) was revisited, supplemented by a targeted revision focusing on validation sample locations that were identified as possibly changed using the BFAST time series algorithm. Additionally, 6720 sample sites were collected to represent possible land cover change areas within 2015 and 2019. Through this updating mechanism, we increased the sampling intensity of validation sample sites in possible land cover change areas within the period. Next, the dataset was used to validate the annual GLC maps of the CGLS-LC100 product for 2015–2019. The results showed that the CGLS-LC100 annual GLC maps have about 80% overall accuracy showing high temporal consistency in general. In terms of stability in class accuracy, herbaceous wetland class showed to be the least stable over the period. As more operational land cover monitoring efforts are upcoming, we emphasize the importance of updated map validation and recommend improving the current validation practices and guidelines towards operational map validation so that long-term land cover maps and their uncertainty information are well understood and properly used.

International audience; Vegetation phenology obtained from time series of remote sensing data is relevant for a range of ecological applications. The freely available Sentinel-2 imagery at a 10 m spatial resolution with a similar to 5-day repeat cycle provides an opportunity to map vegetation phenology at an unprecedented fine spatial scale. To facilitate the production of a Europe-wide Copernicus Land Monitoring Sentinel-2 based phenology dataset, we design and evaluate a framework based on a comprehensive set of ground observations, including eddy covariance gross primary production (GPP), PhenoCam green chromatic coordinate (GCC), and phenology phases from the Pan-European Phenological database (PEP725). We test three vegetation indices (VI) - the normalized difference vegetation index (NDVI), the two-band enhanced vegetation index (EVI2), and the plant phenology index (PPI) - regarding their capability to track the seasonal trajectories of GPP and GCC and their performance in reflecting spatial variabilities of the corresponding GPP and GCC phenometrics, i.e., start of season (SOS) and end of season (EOS). We find that for GPP phenology, PPI performs the best, in particular for evergreen coniferous forest areas where the seasonal variations in leaf area are small and snow is prevalent during wintertime. Results are inconclusive for GCC phenology, for which no index is consistently better than the others. When comparing to PEP725 phenology phases, PPI and EVI2 perform better than NDVI regarding the spatial correlation and consistency (i.e., lower standard deviation). We also link VI phenometrics at various amplitude thresholds to the PEP725 phenophases and find that PPI SOS at 25% and PPI EOS at 15% provide the best matches with the ground-observed phenological stages. Finally, we demonstrate that applying bidirectional reflectance distribution function correction to Sentinel-2 reflectance is a step that can be excluded for phenology mapping in Europe.

Altres ajuts: this research was funded by European Commission/Joint Research Centre under the Framework Service Contract N◦199494 of the Copernicus Global Land Service. The Copernicus Global Land Service (CGLS) provides global time series of leaf area index (LAI), fraction of absorbed photosynthetically active radiation (fAPAR) and fraction of vegetation cover (fCOVER) data at a resolution of 300 m and a frequency of 10 days. We performed a quality assessment and validation of Version 1 Collection 300 m products that were consistent with the guidelines of the Land Product Validation (LPV) subgroup of the Committee on Earth Observation System (CEOS) Working Group on Calibration and Validation (WGCV). The spatiotemporal patterns of Collection 300 m V1 LAI, fAPAR and fCOVER products are consistent with CGLS Collection 1 km V1, Collection 1 km V2 and Moderate Resolution Imagery Spectroradiometer Collection 6 (MODIS C6) products. The Collection 300 m V1 products have good precision and smooth temporal profiles, and the interannual variations are consistent with similar satellite products. The accuracy assessment using ground measurements mainly over crops shows an overall root mean square deviation of 1.01 (44.3%) for LAI, 0.12 (22.2%) for fAPAR and 0.21 (42.6%) for fCOVER, with positive mean biases of 0.36 (15.5%), 0.05 (10.3%) and 0.16 (32.2%), respectively. The products meet the CGLS user accuracy requirements in 69.1%, 62.5% and 29.7% of the cases for LAI, fAPAR and fCOVER, respectively. The CGLS will continue the production of Collection 300 m V1 LAI, fAPAR and fCOVER beyond the end of the PROBA-V mission by using Sentinel-3 OLCI as input data.

This Algorithm Theoretical Basis Document (ATBD)describes in detail the methodology used to producethe third collection of the 100m Land Cover product, the global annual maps for the period 2015-2019, that was released under the global component of the Copernicus Land Monitoring Service. The methodology covers the retrieval and pre-processing of Earth Observation satellite (PROBA-V) observations, the calculation of metrics, the main classification, the regression forthe versatile cover fraction layers, the time series break detectionand so on. Next to the detailed ATBD, a summary Product User Manual describes the product (methodology, quality, contents and format) and Validation Report(s) provide more details on the validation and quality of the product.

The Copernicus Global Land Service has newly released yearly global land cover layers from 2015 onwards. Since one static global map cannot fit the needs of different user communities, Copernicus went the next step and provides dynamic land cover layers which allow to tune the map to your own needs, i.e. Forest monitoring, Sustainable Development Goals, biodiversity or ecosystem services monitoring. Therefore, the land cover layers provide next to a standard classified map also a set of continuous cover layers (forest, shrubland, herbaceous vegetation, cropland, moss & lichens, wetland, bare, built-up, and permanent water). These cover fractions ease the mapping in different schemes (i.e. Land Cover Classification System (LCCS) or Common International Classification of Ecosystem Services (CICES)), facilitating the usage into decision making systems that allow authorities to manage and report. These covers can also be extend well-known high quality continental land cover maps as European Coordinating of Information on the Environment (CORINE) land cover map or the American National Land Cover Database (NLCD) to a global scale. This paper presents a method to extend the European CORINE land cover globally using the Copernicus Global Land Cover layers.

ThisProduct User Manual (PUM) provides a summary description of the 100m Land Cover products, covering the retrieval methodology, the validation results as well asthe products contents and format. The PUM is the starting point into the product's documentation. For more details on the methodology for calculating the land cover maps from PROBA-V satellite observations, please see the related Algorithm Theoretical Basis Document (ATBD). Likewise, the quality and validation information for this product is more extensively covered in the related Validation Report.

This Algorithm Theoretical Basis Document (ATBD)describes in detail the methodology used to producethe first version, over Africa, of the 100m Land Cover product that was released under the global component of the Copernicus Land Monitoring Service. The methodology covers the retrieval and pre-processing of Earth Observation satellite (PROBA-V) observations, the calculation of metrics, the main classification, the regression forthe versatile cover fraction layers and so on. Next to the detailed ATBD, a summary Product User Manual describes the product (methodology, quality, contents and format) and Validation Report(s) provide more details on the validation and quality of the product.

International audience; PROBA-V instrument launched in 2013 is offering a global daily coverage at pixel resolutions of 333 m and 1 km in three spectral bands (BLUE, RED, NIR) and 600 m for shortwave infrared (SWIR). The PROBA-V mission is the follow-on of the VEGETATION program started in 2000, which allowed generating long-term series at 1 km pixel resolution. The PROBA-V products belong to the Copernicus Global Land Service portfolio (http://land. copernicus.eu/global/). The sensor design of PROBA-V with oriented cameras offers a wide field of view (FOV) for sampling the BRDF (Bidirectional Reflectance Distribution Function). This paper details the methodology implemented at the premises of VITO (Flemish Institute for Technological Research) with the aim to disseminate routinely from PROBA-V daily observations for both surface albedo (SA) and top-of-canopy corrected reflectance (TOC-R) products. The method classically operates a selection of cloudless scenes, performs atmospheric corrections, and finally applies a correction of directional effects on a pixel per pixel basis. The synthesis period is the decade and the composite period is 20 days. Such choice is a pointwise sampling as being a trade-off between the availability of clear scenes and the timescale for phenology. Regarding the albedo catalogue, a narrow-band to broadband conversion is stipulated. A recurrent technique serves for gap-filling based on the spread of weighed a priori data. Additional information concerns the quality flag and the age of the product. Preliminary accuracy assessment is performed through a comparison with the Moderate Imaging Spectroradiometer (MODIS) Collection 6. Dependable spatial consistency is reached except for wintertime with deviations in terms of rmse (root mean square errors) about 0.03 for visible and shortwave domains, and 0.04 for near infrared. Besides, both PROBA-V and MODIS C6 exhibit close time profiles, marked by smoothness or rapid transitions. Results over 10 confidence sites reveals rmse values of 0.032 and bias of 0.01 over the 2014 full annual cycle.

This study investigates the scientific quality of the GEOV1 Leaf Area Index (LAI), Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) and Fraction of Vegetation Cover (FCover) products based on PROBA-V observations. The procedure follows, as much as possible, the guidelines, protocols and metrics defined by the Land Product Validation (LPV) group of the Committee on Earth Observation Satellite (CEOS) for the validation of satellite-derived land products. This study is focused on the consistency of SPOT/VGT and PROBA-V GEOV1 products developed in the framework of the Copernicus Global Land Services, providing an early validation of PROBA-V GEOV1 products using data from November 2013 to May 2014, during the overlap period (November 2013-May 2014). The first natural year of PROBA-V GEOV1 products (2014) was considered for the rest of the quality assessment including comparisons with MODIS C5. Several criteria of performance were evaluated including product completeness, spatial consistency, temporal consistency, intra-annual precision and accuracy. Firstly, and inter-comparison with both spatial and temporal consistency were evaluated with reference satellite products (SPOT/VGT GEOV1 and MODIS C5) are presented over a network of sites (BELMANIP2.1). Secondly, the accuracy of PROBA-V GEOV1 products was evaluated against a number of concomitant agricultural sites is presented. The ground data was collected and up-scaled using high resolution imagery in the context of the FP7 ImagineS project in support of the evolution of Copernicus Land Service. Our results demonstrate that GEOV1 PROBA-V products were found spatially and temporally consistent with similar products (SPOT/VGT, MODISC5), and good agreement with limited ground truth data with an accuracy (RMSE) of 0.52 for LAI, 0.11 for FAPAR and 0.14 for FCover, showing a slight bias for FCover for higher values.

ThisProduct User Manual (PUM) provides a summary description of the 100m Land Cover products, covering the retrieval methodology, the validation results as well asthe products contents and format. The PUM is the starting point into the product's documentation. For more details on the methodology for calculating the land cover maps from PROBA-V satellite observations, please see the related Algorithm Theoretical Basis Document (ATBD). Likewise, the quality and validation information for this product is more extensively covered in the related Validation Report. In May 2019, following the release of the first global 100m land cover maps, with asecond version of the algorithm and improved quality, the first version maps over Africa are no longer publicly available.

This Algorithm Theoretical Basis Document (ATBD)describes in detail the methodology used to producethe first version, over Africa, of the 100m Land Cover product that was released under the global component of the Copernicus Land Monitoring Service. The methodology covers the retrieval and pre-processing of Earth Observation satellite (PROBA-V) observations, the calculation of metrics, the main classification, the regression forthe versatile cover fraction layers and so on. Next to the detailed ATBD, a summary Product User Manual describes the product (methodology, quality, contents and format) and Validation Report(s) provide more details on the validation and quality of the product. In May 2019, following the release of the first global 100m land cover maps, with asecond version of the algorithm and improved quality, the first version maps over Africa are no longer publicly available.

This contribution describes an ongoing effort, within the framework of the Copernicus Global Land Service 1, to develop an updated PROBA-V 300m NDVI product. Unlike previous versions of the PROBA-V NDVI at 300m, a normalisation for viewing and illumination geometry is performed and its temporal compositing strategy is aimed to maintain near real-timeness as possible. We use the MSG/SEVIRI NDVI angular normalised time series with high temporal resolution (daily cadence) to evaluate the near real-timeness of the PROBA-V NDVI 300m compositing strategy. Since PROBA-V does not have on-board propellant, the overpass times are expected to gradually differ from the at-launch value. Therefore, an angular normalised PROBA-V NDVI 300m product becomes pivotal to ensure continuity with the Sentinel 3 missions.

The Copernicus Global Land service provides continuously a set of bio-geophysical variables describing, over the whole globe, the vegetation dynamic, the energy budget at the continental surface and some components of the water cycle. These generic products serve numerous applications including agriculture and food security monitoring. The portfolio of the Copernicus Global Land service contains Essential Climate Variables like the Leaf Area Index (LAI), the Fraction of PAR absorbed by the vegetation (FAPAR), the surface albedo, the Land Surface Temperature, the soil moisture, the burnt areas, the areas of water bodies, and additional vegetation indices. They are generated every hour, every day or every 10 days on a reliable automatic basis from Earth Observation satellite data. Beside this timely production, the available historical archives have been processed, using the same innovative algorithms, to get consistent time series as long as possible. All products are accessible, free of charge after registration through FTP/HTTP (http://land.copernicus.eu/global/) and through the GEONETCast satellite distribution system. The evolution of the service towards the operations at 333m resolution is partly supported by the FP7/ImagineS project which focuses on the retrieval of LAI, FAPAR, fraction of vegetation cover and surface albedo from PROBA-V sensor data. The paper presents the innovations of the 333m biophysical products, make an overview of their current status, and introduce the next steps of the evolution of the Copernicus Global Land service.

International audience; a r t i c l e i n f o Essential climate variables such as LAI or FAPAR are required for the monitoring, understanding and modeling of land surfaces at the global scale. While several products were already developed from the current medium resolution sensors, the few validation exercises currently achieved highlighted significant discrepancies and inconsistencies. The objective of this study is to develop improved global estimates of LAI, FAPAR and FCOVER variables by capitalizing on the development and validation of already existing products. In a first step, the performances of the MODIS, CYCLOPES, GLOBCARBON and JRC-FAPAR products were reviewed. The MODIS and CYCLOPES products were then selected since they provide higher level of consistency. These products were fused to generate the improved LAI, FAPAR and FCOVER values that were later scaled to closely match their expected range of variation. Finally, neural networks were trained to estimate these fused and scaled products from SPOT-VEGETATION top of canopy directionally normalized reflectance values. The resulting GEOV1 products are associated to quality control flags as well as quantitative estimates of uncertainties. Performances of the GEOV1 products are finally evaluated in a companion paper. The GEOV1 products are freely available to the community at www.geoland2.eu from 1999 up to present, globally at 1/112° spatial sampling grid at the dekadal time step.

Concentration profiles of nitric oxide, oxygen atoms and fuel fragment radicals such as CH, CH2 and C2 were measured by means of molecular-beam sampling and mass spectrometric detection in a number of hydrocarbon/oxygen/nitrogen flames. The fuel was ethylene, ethane or methane. Temperature profiles were also determined. It was found that even in hot, fuel-lean flames, the Zeldovich mechanism cannot account for the rapid NO formation in the flame front. On the other hand, observed NO production rates downstream of the primary reaction zone are in agreement with the Zeldovich mechanism. The values obtained in the region T=1880–2350 K for the rate constant of O+N2→NO+N deviate on the average only 20% from the expression k=7.5 1013 exp(−76,000/RT) mole−1 cm3 sec−1, proposed by Baulch et al. The observed NO generation rate in the flame front of all the flames investigated can be well represented by 8 1011 [CH][N2] exp(−11,000/RT) (in units of mole, cm3, sec) but almost equally well by 2.8 1012 [CH2][N2] exp(−22,500/RT). Since the respective frequency factors as well as the activation energies are close to the expected values for the reactions CH(2Π)+N2→HCN+N(4S) (spin change=+1) and CH2+N2→HCN+NH, it is concluded that both these processes—in each case followed by rapid oxidation of the products—may be the principal sources of NO in the flame front.

Observations are key to understand the drivers of biodiversity loss, and the impacts on ecosystem services and ultimately on people. Many EU policies and initiatives demand unbiased, integrated and regularly updated biodiversity and ecosystem service data. However, efforts to monitor biodiversity are spatially and temporally fragmented, taxonomically biased, and lack integration in Europe. EuropaBON aims to bridge this gap by designing an EU-wide framework for monitoring biodiversity and ecosystem services. EuropaBON harnesses the power of modelling essential variables to integrate different reporting streams, data sources, and monitoring schemes. These essential variables provide consistent knowledge about multiple dimensions of biodiversity change across space and time. They can then be analyzed and synthesized to support decision-making at different spatial scales, from the sub-national to the European scale, through the production of indicators and scenarios. To develop essential biodiversity and ecosystem variables workflows that are policy relevant, EuropaBON is built around stakeholder engagement and knowledge exchange (WP2). EuropaBON will work with stakeholders to identify user and policy needs for biodiversity monitoring and investigate the feasibility of setting up a center to coordinate monitoring activities across Europe (WP2). Together with stakeholders, EuropaBON will assess current monitoring efforts to identify gaps, data and workflow bottlenecks, and analyse cost-effectiveness of different schemes (WP3). This will be used to co-design improved monitoring schemes using novel technologies to become more representative temporally, spatially and taxonomically, delivering multiple benefits to users and society (WP4). Finally, EuropaBON will demonstrate in a set of showcases how workflows tailored to the Birds Directive, Habitats Directive, Water Framework Directive, Climate and Restoration Policy, and the Bioeconomy Strategy, can be implemented (WP5).

The depressive effect of sulphate and phosphate anions on the calcium atomic-absorption signal was studied in an air-acetylene flame. During the solute nebulisation calcium sulphate and pyrophosphate aerosol particles are formed. The vaporisation of these particles will be the rate-determining step in the atom-formation process. It follows from this fact that no linear relation exists between the measured absorbance and the analyte concentration.