@misc{NaekeMiesnerIngemanNielsenetal., author = {N{\"a}ke, Luisa and Miesner, Frederieke and Ingeman-Nielsen, Thomas and Boike, Julia and Ghoreishian Amiri, Seyed Ali}, title = {Numerical modeling to estimate the impact of built infrastructure on permafrost degradation - Case study from Ilulissat, Greenland}, series = {Book of abstracts, EUCOP6}, journal = {Book of abstracts, EUCOP6}, editor = {Fern{\´a}ndez-Fern{\´a}ndez, Jos{\´e} M.}, doi = {10.52381/EUCOP6.abstracts.1}, pages = {166}, abstract = {Infrastructure in permafrost landscapes affects the ground thermal regime and may enhance permafrost degradation. Stability and usability of the infrastructure depend likewise on the thermal conditions of the subsurface. Permafrost in the study area in Ilulissat (West Greenland) is typically warm and often ice-rich, so infrastructure is likely to accelerate thawing of the ground. Numerical models can be used to estimate the influence of infrastructure on permafrost development, subsidence, and ponding near roads. In this study, we investigated the influence of roads in Ilulissat using the one-dimensional, laterally coupled heat-transfer model CryoGrid. We used ERA5 reanalysis data (1980-2020) and projections according to the SSP5-8.5 scenario (2020-2100) as climate forcing and validated them with site data from the local weather station (1991-2021). Borehole data from Ilulissat and the north-eastern surroundings provide information on soil stratigraphy properties to first built the model for the natural, undisturbed tundra. In the second model set up, we added the elevated gravel embankment as linear infrastructure to the model with several tiles for the roadway and the shoulder. In a third model run, we quantified the effect of snow by changing the snow distribution near the road to imitate plowing. We utilized measured data from the weather station and iButtons for validation of the model runs. Our simulation show that the construction of a road had a direct influence on the thermal regime by warming the soil. A general deepening of the active layer is projected within the current century, which is supported by borehole observations. Likewise, the associated measures of maintenance such as accumulation of cleared snow affect the response of the soil, as an insulator of the embankment, preventing stored heat from escaping. As the current state permafrost is vulnerable to climate change, it is important to rely on models to provide realistic projections.}, language = {en} }