Analyzing Climate Change Impacts on European Cultural Heritage Sites Using High-Temporal-Resolution Satellite Time Series

Kurzfassung

This study investigates the derivation and use of Earth observation-based datasets and products to analyze and understand the impacts of climate change on selected cultural heritage sites in Europe. Conducted as part of the Horizon Europe Triquetra Project, this research utilized high-temporal-resolution satellite time series data from multiple sensors. Specifically, we examined long-term changes in snow cover, coastline morphology, and vegetation drought effects to evaluate their implications for these culturally significant landscapes. At the Kalapodi archaeological site in Greece, snow cover extent was analyzed using binary masks derived from DLR Global SnowPack daily snow cover products for the period 2000–2022 These products, generated using MODIS sensors on the Terra and Aqua satellites, provide daily snow cover data at a 500-meter resolution. The data were aggregated into monthly composites to identify temporal trends and multidecadal means. Comparisons with global climate model snowfall data provided valuable insights into the relationship between observed snow cover dynamics and climatic variables. The analyses at Kalapodi highlights the importance of continuous snow cover monitoring using EO data and emphasize the need of long-term space-borne missions to support continued observation, ensuring effective site management and sustainable conservation in the face of climate change. For drought analysis at Roseninsel, Lake Starnberg, Germany, Terra MODIS Enhanced Vegetation Index (EVI) time series from 2000 to 2022 were used to detect vegetation anomalies. Significant drought-induced stress was observed, particularly in the summers and autumns of 2003, 2004, and 2008, offering valuable insights into vegetation response and supporting improved management of vegetated areas to mitigate erosion risks. The coastline detection approach integrates three primary methods: cloud-processing of annual water index images, local coastline extraction, and the creation of shore-normal transects. Using multispectral Landsat surface reflectance data from various instruments (TM, ETM+, OLI) we generated annual water-index composites based on the Modified Normalized Difference Water Index (MNDWI). These composites facilitated the delineation of sub-pixel shorelines and the quantification of coastline changes through linear regression techniques. Additionally, a high spatial resolution PlanetScope optical yearly time series with a 3 m resolution were employed, providing enhanced precision and frequency for shoreline morphology analyses. This study demonstrates the capability of remote sensing techniques to monitor environmental changes and their impacts on cultural heritage sites, offering valuable tools for climate change adaptation and preservation efforts.