global urban footprint available

global urban footprint available

Global Urban Footprint (GUF) by DLR (Thomas Esch) for Italy to Croatia.

Global Urban Footprint (GUF) by DLR (Thomas Esch) for Italy to Croatia.

The Global Urban Footprint by DLR (Thomas Esch) has been released and provides a global coverage of urbanized areas. Previous versions of this data set has already been used by ongoing research in our department and we will now update the data for our scientific work. It is a great source for mapping human impact on a global scale.  From the DLR website: Currently, more than half of the world’s population are urban dwellers and this number is still rapidly increasing. Since settlements – and urban areas in particular – represent the centers of human activity, the environmental, economic, political, societal and cultural impacts of urbanization are far-reaching. They include negative aspects like the loss of natural habitats, biodiversity and fertile soils, climate impacts, waste, pollution, crime, social conflicts or transportation and traffic problems, making urbanization to one of the most pressing global challenges. Accordingly, a profound understanding of the global spatial distribution and evolution of human settlements constitutes a key element in envisaging strategies to assure sustainable development of urban and rural settlements.

In this framework, the objective of the “Global Urban Footprint” (GUF) project is the worldwide mapping of settlements with unprecedented spatial resolution of 0.4 arcsec (~12 m). A total of 180 000 TerraSAR-X and TanDEM-X scenes have been processed to create the GUF. The resulting map shows the Earth in three colors only: black for “urban areas”, white for “land surface” and grey for “water”. This reduction emphasizes the settlement patterns and allows for the analysis of urban structures, and hence the proportion of settled areas, the regional population distribution and the arrangement of rural and urban areas. More details at: www.dlr.de/guf

Further data portals and visualizations are available here:
Via U-TEP Website: https://urban-tep.eo.esa.int
U-TEP Geobrowser: https://urban-tep.eo.esa.int/geobrowser/?id=guf

and a ESA GUF article: http://www.esa.int/Our_Activities/Observing_the_Earth/New_map_offers_precise_snapshot_of_human_life_on_Earth

MSc handed in: SAR for urban area characterization

MSc handed in: SAR for urban area characterization

TTobiasSieg_SAR_urban_MSc_DLR_GCEobias Sieg submitted his MSc thesis “The potential of interferometric and polarimetric SAR data to characterize urban areas at the example of Mumbai and Manila” successfully and started with his PhD soon after. The thesis has been conducted in close cooperation with the DLR-EOC (Schmidt, Taubenböck) within the Global Change Ecology MSc study program. A publication is aimed at and is planned to be submitted within the end of this year. The studies, conducted in the course of this thesis, prove the feasibility of interferometric and polarimetric SAR data to separate between urban areas with different apparent structures. Further studies should aim for investigating an improvement of this separation and its reliability e.g. by means of polarimetric SAR data with an even higher spatial resolution or the use of enhanced TanDEM-X datasets. However, the use of SAR products with a spatial resolution lower than 2 meters is very limited. Furthermore, this thesis proves the suitability of the framework of the Kennaugh elements and the Schmittlet coefficients to characterize and separate urban areas. Especially the use of the Schmittlet coefficients to assess structures of cities in the future is highly recommended. Also, the use of nDSM data in conjunction with the Schmittlet coefficients is proved to increase the separability between building areas with different building heights tremendously. Once these results are further approved by the application of better suited datasets and the conduction of the methods to a few more cities, they could potentially serve as an helpful source of information for many other studies dealing with urban environments. For example, the results of the area-wide separability of chapter 4 could serve as an pre-classification to detect informal settlements, which could be helpful for urban planners. Also with regard to urban climate, information about the height and the structure or density can help to improve urban climate models. The estimation of the number of inhabitants of a city could benefit from a reliable pre-classification.

Global Urbanization

Global Urbanization

Globale_UrbanisierungBook “Global Urbanization – Perspective from space” published with Springer Spektrum

In the year 2050 there will be 6 billion people living in cities all over the world. This dramatic migration of mankind into the cities has massive impacts on global settlements: especially in Asia, Africa and South America cities with millions of inhabitants are developing rapidly; megacities grow almost unstoppably and create new dimensions of urbanization such as megaregions with more than 100 million inhabitants. Many different kinds of urban structures are formed in this process of urbanization: e.g. decentralized agglomerations of high-rise buildings, monotonous suburbias or slum dwellings. These structures can be identified from space, using multisensoral remote sensing data.

In this book the focus is on transforming multisensoral Earth observation data into new geographic notions. We answer questions such as “which megacities have the highest rates of urban expansion?“, “which spatial patterns of settlements are existing?”, are informal settlements or planned suburbs morphologically similar across the globe?“, “are current urban population estimates correct?“, “how do refugee camps turn into permant settlements?“, “where are the global hubs of NO2 atmospheric loading?” or “can we observe systematics in people sensing the city and the urban structure?”. In addition, these matter-of-fact scientific analyses from space are connected with reports of people sensing the atmosphere of cities.

Beyond this, well-known experts in the fields of remote sensing, geo-informatics, urban geography, sociology or socio-economy discuss requirements, expectations and challenges for urban remote sensing for the future.

This book is published at SpringerSpektrum: http://www.springer.com/de/book/9783662448403