TY - JOUR A1 - Hemmerle, Hannes A1 - Hale, Sina A1 - Dressel, Ingo A1 - Benz, Susanne A1 - Attard, Guillaume A1 - Blum, Philipp A1 - Bayer, Peter T1 - Estimation of Groundwater Temperatures in Paris, France JF - Geofluids N2 - Subsurface temperature data is usually only accessible as point information with a very limited number of observations. To spatialize these isolated insights underground, we usually rely on interpolation methods. Unfortunately, these conventional tools are in many cases not suitable to be applied to areas with high local variability, like densely populated areas, and in addition are very vulnerable to uneven distributions of wells. Since thermal conditions of the surface and shallow subsurface are coupled, we can utilize this relationship to estimate shallow groundwater temperatures from satellite-derived land surface temperatures. Here, we propose an estimation approach that provides spatial groundwater temperature data and can be applied to natural, urban, and mixed environments. To achieve this, we combine land surface temperatures with anthropogenic and natural processes, such as downward heat transfer from buildings, insulation through snow coverage, and latent heat flux in the form of evapotranspiration. This is demonstrated for the city of Paris, where measurements from as early as 1977 reveal the existence of a substantial subsurface urban heat island (SUHI) with a maximum groundwater temperature anomaly of around 7 K. It is demonstrated that groundwater temperatures in Paris can be well predicted with a root mean squared error of below 1 K by means of satellite-derived land surface images. This combined approach is shown to improve existing estimation procedures that are focused either on rural or on urban conditions. While they do not detect local hotspots caused by small-scaled heat sources located underground (e.g., sewage systems and tunnels), the findings for the city of Paris for the estimation of large-scale thermal anomalies in the subsurface are promising. Thus, the new estimation procedure may also be suitable for other cities to obtain a more reliable insight into the spatial distribution of urban ground and groundwater temperatures. UR - https://doi.org/10.1155/2019/5246307 Y1 - 2019 UR - https://doi.org/10.1155/2019/5246307 UR - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:573-35817 SN - 1468-8123 VL - 2019 PB - Hindawi CY - London ER - TY - JOUR A1 - Pophillat, William A1 - Attard, Guillaume A1 - Bayer, Peter A1 - Hecht-Méndez, Jozsef A1 - Blum, Philipp T1 - Analytical solutions for predicting thermal plumes of groundwater heat pump systems JF - Renewable Energy UR - https://doi.org/10.1016/j.renene.2018.07.148 Y1 - 2018 UR - https://doi.org/10.1016/j.renene.2018.07.148 SN - 1879-0682 VL - 2020 IS - 147, Part 2 SP - 2696 EP - 2707 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Attard, Guillaume A1 - Bayer, Peter A1 - Rossier, Yvan A1 - Blum, Philipp A1 - Eisenlohr, Laurent T1 - A novel concept for managing thermal interference between geothermal systems in cities JF - Renewable Energy UR - https://doi.org/10.1016/j.renene.2019.06.095 Y1 - 2019 UR - https://doi.org/10.1016/j.renene.2019.06.095 SN - 1879-0682 VL - 2020 IS - 145 SP - 914 EP - 924 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Pophillat, William A1 - Bayer, Peter A1 - Teyssier, Esther A1 - Blum, Philipp A1 - Attard, Guillaume T1 - Impact of groundwater heat pump systems on subsurface temperature under variable advection, conduction and dispersion JF - Geothermics UR - https://doi.org/10.1016/j.geothermics.2019.101721 Y1 - 2019 UR - https://doi.org/10.1016/j.geothermics.2019.101721 SN - 1879-3576 VL - 2020 IS - 83 PB - Elsevier CY - Amsterdam ER -