Digital world meets urban planet – new prospects for evidence-based urban studies arising from joint exploitation of big earth data, information technology and shared knowledge

The digital transformation taking place in all areas of life has led to a massive increase in digital data – in particular, related to the places where and the ways how we live. To facilitate an exploration of the new opportunities arising from this development the Urban Thematic Exploitation Platform (U-TEP) has been set-up. This enabling instrument represents a virtual environment that combines open access to multi-source data repositories with dedicated data processing, analysis and visualisation functionalities. Moreover, it includes mechanisms for the development and sharing of technology and knowledge. After an introduction of the underlying methodical concept, this paper introduces four selected use cases that were carried out on the basis of U-TEP: two technology-driven applications implemented by users from the remote sensing and software engineering community (generation of cloud-free mosaics, processing of drone data) and two examples related to concrete use scenarios defined by planners and decision makers (data analytics related to global urbanization, monitoring of regional land-use dynamics). The experiences from U-TEP’s pre-operations phase show that the system can effectively support the derivation of new data, facts and empirical evidence that helps scientists and decision-makers to implement improved strategies for sustainable urban development

EnMAP User Interface - An Overview of EnMAP ground segment services

EnMAP (Environmental Mapping and Analysis Program) is a future German hyperspectral satellite mission providing high quality hyperspectral image data on a timely and frequent basis. Main objective is to investigate a wide range of ecosystem parameters encompassing agriculture, forestry, soil and geological environments, coastal zones and inland waters. The EnMAP Ground Segment will be realized and operated by the German Aerospace Center (DLR) covering all aspects relevant to assure successful mission operations. This comprises controlling and commanding the satellite using multi-mission infrastructures as well as data reception, hyperspectral data processing including calibration, data archiving, data dissemination, and providing web-interfaces to the international user community. From the users´ point of view there are two major scenarios of particular interest. First the handling of image acquisitions based on user requests and second the generation of standardized products based on acquisitions or archive orders by users. This paper provides details on the concepts, design and functionalities of the EnMAP user interface, which consists of two online portals interfaced with several subsystems of the EnMAP Ground Segment: First the EnMAP Portal (www.enmap.org) provides general EnMAP mission information. It is the central entry point for all users interested to learn about the EnMAP mission, its objectives, status, and results. Second the EnMAP Data Access Portal links to a set of functions for registered users that will support the international EnMAP user community. This portal includes amongst others a proposal portal allowing submission of proposal for all users responding to a Data Announcement of Opportunity (AO). The proposals and the associated results will be presented by an interactive map supporting the establishment of a worldwide user network and guarantee the highest transparency of the proposal process. Observation requests are issued to order EnMAP data takes and provides all information required for scheduling data takes such as location and extension of the observation area, acquisition time frame, sensor look angle and required data products. Additionally, the platform informs about the conditions and requirements for the EnMAP data access and the ongoing scientific programs and activities. The catalogue browse and order service (EOWEB portal) allows browsing and ordering of EnMAP data products that have previously been acquired, processed, and archived in the product library. The operational services offered through the EnMAP (Data Access) Portal will be complemented by a service team, EnMAP Application Support, offering expert advice on the exploitation of EnMAP data

Exploiting Big Earth Data from Space – First Experiences with the TimeScan Processing Chain

The European Sentinel missions and the latest generation of the United States Landsat satellites provide new opportunities for global environmental monitoring. They acquire imagery at spatial resolutions between 10 and 60 m in a temporal and spatial coverage that could before only be realized on the basis of lower resolution Earth observation data (>250 m). However, images gathered by these modern missions rapidly add up to data volume that can no longer be handled with standard work stations and software solutions. Hence, this contribution introduces the TimeScan concept which combines pre-existing tools to an exemplary modular pipeline for the flexible and scalable processing of massive image data collections on a variety of (private or public) computing clusters. The TimeScan framework covers solutions for data access to arbitrary mission archives (with different data provisioning policies) and data ingestion into a processing environment EO2Data module), mission specific pre-processing of multi-temporal data collections (Data2TimeS module), and the generation of a final TimeScan baseline product (TimeS2Stats module) providing a spectrally and temporally harmonized representation of the observed surfaces. Technically, a TimeScan layer aggregates the information content of hundreds or thousands of single images available for the area and time period of interest (i.e. up to hundreds of TBs or even PBs of data) into a higher level product with significantly reduced volume. In first test, the TimeScan pipeline has been used to process a global coverage of 452,799 multispectral Landsat–8 scenes acquired from 2013 to 2015, a global data-set of 25,550 Envisat ASAR radar images collected 2010–2012, and regional Sentinel–1 and Sentinel–2 collections of ∼1500 images acquired from 2014 to 2016. The resulting TimeScan products have already been successfully used in various studies related to the large-scale monitoring of environmental processes and their temporal dynamics

User Interfaces of EnMAP

The objectives of the high-resolution imaging spectroscopy remote sensing mission EnMAP (Environmental Mapping and Analysis Program) are the investigations of a wide range of Earth surface parameters. The high-quality standardized products will be freely available to international scientific users for measuring and analyzing the status and evolution of various terrestrial and aquatic ecosystems. Therefore, it will cover the spectral range from 420 nm to 2450 nm with a spectral sampling distance varying between 4.8 nm and 12.0 nm. It will acquire 30 km in the across-track direction with a ground sampling distance of 30 m. The launch is scheduled for 2020 with an operational lifetime of 5 years. The EnMAP portal (www.enmap.org) is the central entry point for all users. It provides general mission information, e.g. on the space, ground, and science segment as well as related campaigns. Approximately 5,000 km in the along-track direction will be acquired per day, which are split to several observations. Therefore, the proposal handling and observation planning portal will be established to reasonably distribute the acquisition capacity to the user community. Registered users submit proposals based on Announcement of Opportunities placed by the science segment and mission management. Proposals specify especially the required coverage. If the proposal is accepted, the user plans the observations. The repeat cycle of 398 revolutions in 27 days has an orbit altitude of 652 km and combined with an across-track tilt capability of 30° this enables a target revisit time of less than 4 days. Each region is acquirable in the repeat cycle with an out-of-nadir angle of at most 5°. The local time of descending node is 11:00. Proposals, observations, and associated research will be presented by an interactive map supporting the establishment of a world-wide user network. In case of tasking conflicts, issued observations are prioritized especially based on historical and current cloud coverage information taking satellite constraints such as power and storage into account. All observations will be long-term archived. The catalog search and order service portal will allow all registered users to search and browse products based on the standardized protocols CSW (catalog service for the web) and WMS (web mapping service). Because of the necessary various processing options, each product will specifically be generated for each order and will be delivered using SFTP (secure file transfer protocol). The fully-automatic on-ground processing chain will generate calibrated hyperspectral image products at three levels for the users. Level 1A/1B products are corrected to Top-of-Atmosphere (TOA) radiances including, e.g., defective pixel flagging, non-linearity correction, dark signal (and digital offset) correction, gain matching, straylight correction, radiometric/spectral referencing, radiometric calibration, and spectral defective pixel interpolation (using a simplified pixel-based atmospheric correction). Level 1C products are orthorectified to a user selected map projection (UTM, geographic, or European projection LAEA) and resampling model (nearest neighbor, bi-linear interpolation, or cubic convolution). By the method of direct georeferencing, the physical sensor model, with a correction of sensor interior orientation, satellite motion, light aberration and refraction, and terrain related distortions from raw imagery is applied. Level 2A products are compensated for atmospheric effects to Bottom-of-Atmosphere (BOA) reflectances with separate algorithms for land and water applications. Therefore, a classification (e.g., land-water-background, cloud), aerosol optical thickness and also columnar water vapor estimation is performed to obtain surface or underwater reflectances including an adjacency correction. All processors are complemented by independent data quality control routines. Calibration equipment, especially a doped sphere with spectral features and a full aperture diffuser for Sun calibrations allows achieving a spectral accuracy of better than 1 nm as well as a radiometric accuracy of better than 5%. A geometric accuracy of 100 m is achieved - improved by on-ground processing to 30 m with respect to a used reference image. The offered operational services are complemented by a service team offering expert advice on the exploitation of EnMAP. In order to guarantee high consistency in particular all aspects of user interfaces are realized and operated by the Earth Observation Center (EOC) of the German Aerospace Center (DLR), which has long-lasting experiences with the airborne and spaceborne acquisition, processing, and analysis of hyperspectral data

Earth Observation-Supported Service Platform for the Development and Provision of Thematic Information on the Built Environment – the TEP-Urban Project

The Sentinel fleet will provide a so-far unique coverage with Earth observation data and therewith new opportunities for the implementation of methodologies to generate innovative geo-information products and services. It is here where the TEP Urban project is supposed to initiate a step change by providing an open and participatory platform based on modern ICT technologies and services that enables any interested user to easily exploit Earth observation data pools, in particular those of the Sentinel missions, and derive thematic information on the status and development of the built environment from these data. Key component of TEP Urban project is the implementation of a web-based platform employing distributed high-level computing infrastructures and providing key functionalities for i) high-performance access to satellite imagery and derived thematic data, ii) modular and generic state-of-the art pre-processing, analysis, and visualization techniques, iii) customized development and dissemination of algorithms, products and services, and iv) networking and communication. This contribution introduces the main facts about the TEP Urban project, including a description of the general objectives, the platform systems design and functionalities, and the preliminary portfolio products and services available at the TEP Urban platform

EnMAP - From Data Access, Planning, Processing to Image Product Delivery

EnMAP (Environmental Mapping and Analysis Program) is a German hyperspectral satellite mission anticipated to be launched by end of 2020. The EnMAP Ground Segment will be realized and operated by the German Aerospace Center (DLR) covering all aspects relevant to assure successful mission operations. This comprises amongst others hyperspectral data processing, data archiving, data dissemination, and providing web-interfaces to the international user community. This paper provides a brief insight in the concepts and design of the EnMAP user interfaces, and gives an overview of functionalities from observation request scenarios, data processing to image product delivery. The EnMAP Portal (www.enmap.org) is the central entry point for all users interested to learn about the EnMAP mission, its objectives, status, and results. In contrast the EnMAP Data Access Portal links to a set of functions for registered users that will support the international EnMAP user community. This portal includes planning support and ordering interface for data products based on future EnMAP acquisitions and a proposal portal allowing submission of proposal for all users responding to a Data Announcement of Opportunity (AO). The catalogue and order service (EOWEB® GeoPortal) allows browsing and ordering of EnMAP data products based on Level 0 that have previously been acquired, processed, and archived in the product library. A fully-automatic on-ground processing chain generates standardized calibrated image products at three levels from L1B Top-of-Atmosphere (TOA) radiances, L1C (orthorectified) to L2A atmospherically corrected Bottom-of-Atmosphere (BOA) reflectances with separate/combined algorithms for land and water applications

Earth observation-based service platforms - a new instrument to provide geo-information for urban and regional planning

The upcoming suite of Sentinel satellites in combination with their free and open access data policy will open new perspectives for establishing a spatially and temporally detailed monitoring of the Earth's surface. The Sentinel fleet will provide a so-far unique coverage with Earth observation (EO) data and new possibilities with respect to the implementation of innovative methodologies, techniques and geo-information products and services