In order to obtain actionable information from Earth observation (EO) supporting the green transition, both geometric and physical properties of the Earth must be taken into account. While EO data (e.g. Sentinel-1,2) can describe the physical properties with high temporal resolution through radiometric measurements, the description of the Earth's geometry from S1/2 is rather limited. Therefore, high-resolution topographic models are often used in conjunction with S1/2 data for various applications e.g. environmental modelling, machine learning. Only when these two data sources are combined, a complete image of the Earth can be created, an essential prerequisite for a digital twin of the Earth.
However, access to and processing of topographic data is in strong contrast to the way S1/2 data is used. While S1/2 data is usually stored and processed centrally on a dedicated cloud computing infrastructure, topographic datasets are distributed across different resources and processed locally by each user individually. As a result, both the necessary preprocessing as well as the deviation of commonly used topographic parameters have to be repeated by each user. As a consequence, valuable time is unnecessarily spent on the timely preprocessing rather than on advancing research supporting the green transition. Performing these steps once would not only eliminate repetitive work, but also ensure that all users use the same products in their downstream tasks (e.g. environmental modelling, machine learning), which can make the derived products more comparable and objective.
Therefore, the main goals of TOPO4EO are i) the development of a prototype of a topographic data cube of Austria ii) countrywide calculation of commonly used topographic parameters iii) implementation of new value added products at the intersection of topographic and EO data and iv) organization of workshops and tutorials for potential users. As a result, TOPO4EO will significantly improve the monitoring, prognosis and modeling of environmental processes. To demonstrate its potential, three highly relevant data layers will be calculated using the established infrastructure: An improved, updated high resolution estimation of the above ground biomass (AGB) in forested areas, location of potential natural water retention ponds for sustainable agricultural water management and a vegetation surface change layer. All layers will be calculated for Austria and integrated into GTIF-AT. Hence, TOPO4EO will not only establish a unified framework for other users to implement new value added products but also directly contribute own relevant layers supporting the green and digital transition.
Thus, TOPO4EO is a crucial missing piece to support decision makers in making informed decisions related to the green transition based on harmonized and objective country-wide data. By further using the same infrastructure and interfaces as for S1/2 (e.g. ACube), synergies between topographic and EO data from the Copernicus program are optimally exploited. As the developed prototype could be easily transferred to other countries of the European Union which face similar challenges, TOPO4EO is a step further towards a unified European data space integrating both high resolution topographic and EO data.
