A5021998834- Remote Sensing in Agriculture
- Atmospheric and Environmental Gas Dynamics
- Remote Sensing and Land Use
- Land Use and Ecosystem Services
- Calibration and Measurement Techniques
- Remote Sensing and LiDAR Applications
- Species Distribution and Climate Change
- Atmospheric Ozone and Climate
- Plant Water Relations and Carbon Dynamics
- Climate variability and models
- Ecology and Vegetation Dynamics Studies
- Remote-Sensing Image Classification
- Geophysics and Gravity Measurements
- Meteorological Phenomena and Simulations
- Atmospheric aerosols and clouds
- Forest ecology and management
- Cryospheric studies and observations
- Soil and Land Suitability Analysis
- Urban Heat Island Mitigation
- Plant Ecology and Soil Science
- Solar and Space Plasma Dynamics
- Advanced Image Fusion Techniques
- Engineering Applied Research
- Satellite Image Processing and Photogrammetry
- Atmospheric chemistry and aerosols
Flemish Institute for Technological Research
2012-2024
Research Institute for Nature and Forest
2003
KU Leuven
2003
The ‘rain use efficiency’ (RUE) may be defined as the ratio of above-ground net primary productivity (ANPP) to annual precipitation, and it is claimed a conservative property vegetation cover in drylands, if not subject non-precipitation related land degradation. Consequently, RUE regarded means normalizing ANPP for impact an indicator Large scale long term identification monitoring degradation such Sahel, can only achieved by Earth Observation (EO) data. This paper demonstrates that...
Abstract Ecosystem sensitivity to climate variability varies across East Africa, and identifying the determinant factors of this is crucial assessing region‐wide vulnerability change variability. Such assessment critically relies on spatiotemporal data sets with inherent uncertainty, new processing techniques extract interannual at a priori unknown time scales adequate statistical models test for biogeographical effects vegetation‐precipitation relationships. In study, in long‐term records...
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> A new consistent long-term normalized difference vegetation index (NDVI) time series at a 1- <formula formulatype="inline"><tex>$\hbox{km}^{2}$</tex></formula> resolution for Southern Africa that is based on the data from Satellite Pour l'Observation de la Terre VEGETATION (VGT) (1998–2006) and National Oceanic Atmospheric Administration Advanced Very High Resolution Radiometer (AVHRR)...
After the end of 'Satellite Pour l'Observation de la Terre' (SPOT) VEGETATION (SPOT/VGT) mission in May/2014, SPOT/VGT data archive, consisting raw coming from both 1 (VGT1) and 2 (VGT2) instruments, was reprocessed, aiming at improved cloud screening correcting for known artefacts such as smile pattern VGT2 Blue band Sun-Earth distance bug Top-of-Atmosphere reflectance calculation, with objective improving temporal consistency. The aim this paper is to inform user community changes...
Abstract The Coordinating Earth Observation Data Validation for Reanalysis Climate Services project (CORE-CLIMAX) aimed to substantiate how Copernicus observations and products can contribute climate change analyses. CORE-CLIMAX assessed the European capability provide data records (CDRs) of essential variables (ECVs), prepared a structured process derive CDRs, developed harmonized approach validating variable identified integration CDRs into reanalysis chain, formulated compare results...
Remote sensing is nowadays considered to be a valuable input for the annual collection of crop statistics. Derived maps can serve as baseline yield or area estimation target next year's census. For subsistence farming, where small parcels are mixed with other land use, mapping remains very challenging. This article evaluates potential discriminating crops in West Shewa, an small-scale farming central Ethiopia. A hard classification high-resolution (30 m) images, yielding good results...
Land surface reflectance measurements from the VEGETATION program (SPOT-4, SPOT-5 and PROBA-V satellites) have led to acquisition of consistent time-series Normalized Difference Vegetation Index (NDVI) at a global scale. The wide imaging swath (>2000 km) family space-borne sensors ensures daily coverage Earth expense varying observation illumination geometries between successive orbit overpasses for given target located on ground. Such angular variations infer saw-like patterns NDVI....
The Système Pour l'Observation de la Terre 5 – VEGETATION 2 (SPOT VGT2) instrument started to drift in orbit from early 2011, but currently the overpass time is still within mission requirements (less than 20 min deviation 10:30 local equator crossing time). To determine operational lifetime of VGT2 instrument, it was necessary investigate impact orbital beyond these such that VGT series remains consistent over time. this purpose, on reflectance values and normalized difference vegetation...
Sentinel-3 synergy (SYN) VEGETATION (VGT) products were designed to provide continuity the SPOT/VEGETATION (SPOT VGT) base archive. Since PROBA-V mission acted as a gap filler between SPOT VGT and Sentinel-3, in principle, continuous series of data from combined archives (1998–2014), (2013–2020) SYN (from 2018 onwards) are available users, consistency with both latest (VGT-C3) (PV-C2) is highly relevant. In past years, important changes have been implemented processing baseline. The archive...
ABSTRACT We explore a new method to retrieve seasonal glacier mass balances (MBs) from low-resolution optical remote sensing. derive annual winter and summer snow maps of the Alps during 1998–2014 using SPOT/VEGETATION 1 km resolution imagery. combine these with DEM calculate ‘mean regional’ altitude ( Z ) in region surrounding glacier. Then, we compare interannual variation observed winter/summer MB for 55 Alpine glaciers over 1998–2008, our calibration period. find strong linear...
Environmental change is an important issue in the Andes region. The objectives of this research are to study NDVI dynamics region based on time series analysis SPOT-Vegetation and NOAA-AVHRR, recognize which extent variability can be attributed either climatic or human induced impacts. Correlation between SPI were performed order identify best lag per pixel. Trends SDVI investigated using linear least square regression. Significant vegetation trends found 46% area. Both lead different...
This paper discusses results from 12 months of a Round Robin exercise aimed at the inter-comparison different cloud detection algorithms for Proba-V. Clouds is critical issue satellite optical remote sensing, since potential errors in masking directly translates into significant uncertainty retrieved downstream geophysical products. Cloud particularly challenging Proba-V due to presence limited number spectral bands and lack thermal infrared bands. The main objective project was several over...
PROBA-V (PRoject for On-Board Autonomy–Vegetation) was launched in May-2013 as an operational continuation to the vegetation (VGT) instruments on-board Système Pour l’Observation de la Terre (SPOT)-4 and -5 satellites. The first reprocessing campaign of archive from Collection 0 (C0) 1 (C1) aims at harmonizing time series, thanks improved radiometric geometric calibration cloud detection. evaluation C1 focuses on (i) qualitative quantitative assessment new detection scheme; (ii)...
The objective of this study was to use satellite imagery combined with field-based spectral analysis assess the impacts mining-related activities on vegetation around smelter town Karabash, South Ural Mountains Russia. Time series normalized difference index (NDVI) and fraction absorbed photosynthetically active radiation (FAPAR) images derived from Système Pour l'Observation de la Terre (SPOT)-VEGETATION stress indices calculated 140 in situ measurements. Correlation analyses have revealed...
Systematic scanning of the earth surface could be achieved for first time in 1978, with launch observation system NOAA-AVHRR. Some twenty years later, SPOT-VEGETATION instrument introduced significant improvements at levels image quality, timeliness and availability. Since start April 1998, VITO is responsible central processing, archiving distribution VEGETATION data. This paper briefly announces how a similar service being established to provide same kind data from recently launched METOP-AVHRR.
CISAR, a novel and versatile algorithm for the joint retrieval of surface reflectance aerosol properties, has been applied on PROBA-V observations from years 2014-2015 in framework Advanced Land, Aerosol Coastal products (PV-LAC) ESA project. This allows continuous variation atmospheric state variables solution space as it solves radiative transfer equation online. The inversion is performed with an Optimal Estimation (OE) approach, which finds best balance between information that can be...
Abstract. Spectral consistency with SPOT-VEGETATION is an important mission objective for PROBA-V, in particular its 1 km products. This must allow service providers such as the Copernicus Global Land Service to extend 16-year long timeseries of SPOTVEGETATION global 1km data similar PROBA-V To evaluate extent spectral consistency, evaluation response differences performed by applying and 2 a library representative land cover conditions. Datasets surface reflectance values Normalized...
The Project for On-Board Autonomy–Vegetation (PROBA-V) satellite, operated by the European Space Agency (ESA), provides land surface observations at 300m resolution global vegetation monitoring studies. This letter reports development of phenology (LSP) mapping using PROBA-V data from 2018-2020. LSP processing chain involves calculating nadir bi-directional reflectance distribution function (BRDF)-adjusted (NBAR) top-of-canopy reflectance, computing plant index (PPI), and reconstructing...
Sentinel-3 synergy (SYN) VEGETATION (VGT) products were designed to provide continuity SPOT/VEGETATION (SPOT VGT). In past years, important changes have been implemented in the SYN VGT processing baseline. Since PROBA-V mission acted as a gap filler between SPOT and Sentinel-3, principle continuous series of data from combined archives (1998 – 2014), (2013-2020) (from 2018 onwards) is available users, consistency with both latest (VGT-C3) (PV-C2) highly relevant. Spatio-temporal...
Knowledge about global land cover is an important input for the modelling of ecological and environmental processes. Production such vegetation maps can be facilitated by using automated methods classification. Two neural network strategies, overall class-specific network(s), were tested on a part Europe. This study indicates that sub-pixel proportion estimates assessed quite accurately from 1-km resolution SPOT-VEGETATION imagery.