pThis paper describes a prototype network of automated italicin situ/italic measurements of hyperspectral water reflectance suitable for satellite validation and water quality monitoring. Radiometric validation of satellite-derived water reflectance is essential to ensure that only reliable data, e.g., for estimating water quality parameters such as chlorophyll italica/italic concentration, reach end-users. Analysis of the differences between satellite and italicin situ/italic water reflectance measurements, particularly unmasked outliers, can provide recommendations on where satellite data processing algorithms need to be improved. In a massively multi-mission context, including Newspace constellations, hyperspectral missions and missions with broad spectral bands not designed for “water colour”, the advantage of hyperspectral over multispectral italicin situ/italic measurements is clear. Two hyperspectral measurement systems, PANTHYR (based on the mature TRIOS/RAMSES radiometer) and HYPSTAR$^®$ (a newly designed radiometer), have been integrated here in the WATERHYPERNET network with SI-traceable calibration and characterisation. The systems have common data acquisition protocol, data processing and quality control. The choice of validation site and viewing geometry and installation considerations are described in detail. Three demonstration cases are described: 1. PANTHYR data from two sites are used to validate Sentinel-2/MSI (A&B); 2. HYPSTAR$^®$ data at six sites are used to validate Sentinel-3/OLCI (A&B); 3. PANTHYR and HYPSTAR$^®$ data in Belgian North Sea waters are used to monitor phytoplankton parameters, including italicPhaeocystis globosa/italic, over two 5 month periods. Conclusion are drawn regarding the quality of Sentinel-2/MSI and Sentinel-3/OLCI data, including indications where improvements could be made. For example, a positive bias (mean difference) is found for ACOLITE\_DSF processing of Sentinel-2 in clear waters (Acqua Alta) and clues are provided on how to improve this processing. The utility of these italicin situ/italic measurements, even without accompanying hyperspectral satellite data, is demonstrated for phytoplankton monitoring. The future evolution of the WATERHYPERNET network is outlined, including geographical expansion, improvements to hardware reliability and to the measurement method (including uncertainty estimation) and plans for daily distribution of near real-time data./p
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RBINS Staff Publications 2025
The decarbonization of the heating sector is crucial for the green transition of the energy mix. This study investigates threefold the economic and environmental performance of deep geothermal heating investments in Northern Belgium First, techno-economic and life cycle assessment (LCA) are performed, followed by a global sensitivity analysis focusing on the geological uncertainty. Lastly, real options analysis (ROA) is employed to investigate the economic and environmental value of the investors’ flexibility. A novel ROA method is proposed that considers the LCA results to calculate development decisions that minimize the expected environmental impact of the investment. The results show that the economic and environmental performance of the investment vary with the energy prices and the electricity mix. The performance of the investment is driven by the plant’s pumping requirements, which are induced by the relatively low rock permeability at the targeted location. Also, the results’ variability mainly originates by uncertainty regarding the permeability value. Nevertheless, the investors’ flexibility adds large economic and environmental value to the investment. However, the development strategies that optimize the economic or the environmental performance of the plant present some trade-offs. This study demonstrates that the economic and environmental performance of deep geothermal heating investments in Northern Belgium can be improved by focusing on the factors that simultaneously drive the costs, environmental impacts, and their variability. It also shows that utilizing the investors’ flexibility to optimize the investment’s economic and environmental performance can add significant value to the investment.
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RBINS Staff Publications 2024
