A Simplified InSAR-Based Approach to Assess Subsidence-Induced Impacts: the Hamburg Protected Area

World Heritage (WH) properties and heritage sites in general are exposed to the impacts of natural and man-triggered catastrophic events, which threaten their integrity and may compromise their value. The loss or deterioration of these outstanding properties has severely negative impacts on local and national communities, both because of their cultural importance, and because of their socio-economic value (https://whc.unesco.org/en/disaster-risk-reduction/). In the framework of the H2020-ARCH project a simplified approach was implemented for assessing and monitoring the subsidence hazards and the possible induced damages and short- and long-term impacts that these might cause on the buildings and other structures composing and characterising the WH sites. The InSAR data sets relating to the WH area of the Hamburg city were processed to evaluate the deformation velocity affecting each building, in order to project the Subsidence Related Intensity parameters in the short-and long-term, and thus estimate the expected damage levels through fragility curves. The results show a relatively stable situation in the area, however damage levels of a certain consistency are detectable for a long period due to the differential settlements. Furthermore, the results obtained allow us to evaluate the socio-economic impacts on the basis of some assumptions about potential losses.