The “Urban Areas and Land Management” team addresses a wide range of issues with practical implications. The most important thematic focal points are described below.
Due to their central role in the economy, politics, society and culture, the impact of urban agglomerations usually extends far beyond their actual geographic location. Hence, the sustainable development of human settlements is a key element in the implementation of strategies for sustainable development on regional, national and global scales. The effectiveness of the corresponding concepts depends on such factors as the availability of up-to-date, wide-area, and spatially as well as thematically detailed information on the characteristics and development of urban systems. Up to now, most of the required information and data has been gathered by statistical canvassing, surveying and mapping. However, statistical information often has comparably coarse spatial and temporal resolution, while mapping is very time consuming and thus cost-intensive—character¬istics which significantly restrict regular updating at regional, national and global levels. For such purposes, satellite and aerial earth observation have demonstrated their potential to provide various types of data and information on the urban environment, from the characteristics of single buildings to the global distribution and development of urban areas, and to accomplish this task impartially, with instruments that can be adjusted to meet changing spatial and temporal requirements.
Contact: Thomas Esch
Cultural Landscapes
In contrast to natural landscapes, cultural landscapes have been modified by a long period of human activity. The molding of landscapes and the use of their resources, especially for agriculture and forestry, reflect a process extending over centuries. Conflicts of interest arise because of changing land use expectations. Due to the growth of settlements and the expansion of transport infrastructure, the extraction of raw materials, intensive agriculture and forestry, as well as recreational use, the biotope composition of cultural landscapes has dramatically changed in the last few decades. The preservation of biodiversity, habitat diversity, and the ecological functions of landscapes have only recently come into the focus of public interest. Cultural landscapes, for example in central Europe, benefit from the balanced coexistence of intensively used areas and nature retreats. Therefore, sustainable landscape management is of great importance, and relevant guidelines have found their way into European policies such as the Water Framework Directive, soil conservation directives, and the NATURA 2000 directive relating to the protection of endangered species.Satellite and aerial remote sensing make it possible to gather spatial information about the current status of land use and land cover as well as to monitor changes. In the framework of various Europe-wide programs, such as GMES (Global Monitoring for Environment and Security), databases on land use and land cover based on satellite images are being established.
Contact: Manfred Keil
Vulnerability
The rapid development of satellite systems and the corresponding image analysis techniques have made earth observation a useful tool for identifying, locating and estimating georisks and vulnerability. Diverse information products are available to support planning and relief efforts in anticipation of, during and after a natural disaster.Risk is defined as the future interaction of a hazard with the vulnerability of a system. Radar technology, in particular, is well suited for monitoring and assessing the hazard aspect, and a multisensor approach facilitates vulnerability analysis. Identifying physical exposure, or analyzing spatial patterns to identify small-scale urban structures in a given location are examples of applications. In addition, interdisciplinary approaches are used to develop strategies to minimize risk. These include areal estimates of building stability made in cooperation with civil engineers, determining the time-dependent population distribution with the help of social scientists, and using evacuation modeling to identify infrastructural bottlenecks.
Contact: Hannes Taubenböck
The efficient use of renewable energy resources is an important component of a sustainable energy supply which considers the finiteness of fossil resources as well as the drastic impact of increasing greenhouse gas emissions. In this context, analyses based on remote sensing technology make it possible to extract diverse, wide area energy-relevant information at different spatial resolutions. The “energy” research topic focuses on the characterization of settlement structures and land use to evaluate, for example, the potential of renewable energy resources in specified built-up areas. The spatial referencing of the analyses makes them a very useful aid when making planning decisions. Current studies are undertaken in close cooperation with the “Systems Analysis and Technology Assessment” department of the DLR Institute of Technical Thermodynamics.
The climate within a city differs from that of its environs. The best known phenomenon revealing this effect is the urban heat island, which shows that nighttime temperatures are noticeably higher in urban areas than in their rural surroundings. But other climate parameters such as surface temperature and wind speed also change over urban areas. They are strongly influenced by the type and distribution of buildings, vegetation and impervious surfaces in the urban landscape. The “Urban Climate” thematic focus is on mapping the spatial characteristics that influence the urban (micro) climate. Both optical and thermal remote sensing data are used for this purpose. The products (like detailed land cover and surface temperature maps) are used as input data for (micro) climate models and to derive climate-relevant indicators.
Imperviousness per municipality in Germany based on Landsat data and municipal boundaries.
Quality of Life
The term “quality of life” summarizes parameters and indicators which characterize the living conditions of people, for example with respect to their social-economic, health or environmental situation. The relevant parameters, such as “building density” or “green area per inhabitant,” are commonly derived from statistical data, geoinformation, or a combination of both sources. They are often aggregated for different spatial units, like urban districts or counties. The “Urban Areas and Land Management” team develops methods to identify and quantify these spatial characteristics using various remote sensing data sets, sometimes also in combination with statistical information or cadastral data. In addition, research is carried out on the relationship between the spatial characteristics of urban areas or their surroundings and social-economic as well as climate parameters.
Contact: Michael Wurm