• Energy Research
• 2016-2025close
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In urban areas, the human influence on the city-ecosystem often results in a Subsurface Urban Heat Island (SUHI), which can be used geothermally. Unfortunately, a model of a SUHI does not consider the geology and hydrogeology of the subsoil. These can vary significantly over short distances, and are of considerable importance for the energy balance. In this work, we calculated the energy and its density stored in the subsoil via a SUHI. For this so-called energy-SUHI (e-SUHI), we evaluated the geology and its physical parameters for the first 20 m below ground level in the German city of Nuremberg and linked them to measured underground temperatures in a GIS application. This approach revealed stored energy of 1.634 × 1010 MJ within the soil and water for the study area with an area of 163 km2 and a volume of 3.26 × 109 m3. It corresponds to an average energy density of 5.0 MJ/m3. The highest energy density of 16.5 MJ/m3 was found in the city center area and correlated well to increases in subsurface temperature. As expected, our model reacts sensitively to thickness changes in the geological layers and the unsaturated zone.

In urban areas, the human influence on the city-ecosystem often results in a Subsurface Urban Heat Island (SUHI), which can be used geothermally. Unfortunately, a model of a SUHI does not consider the geology and hydrogeology of the subsoil. These can vary significantly over short distances, and are of considerable importance for the energy balance. In this work, we calculated the energy and its density stored in the subsoil via a SUHI. For this so-called energy-SUHI (e-SUHI), we evaluated the geology and its physical parameters for the first 20 m below ground level in the German city of Nuremberg and linked them to measured underground temperatures in a GIS application. This approach revealed stored energy of 1.634 × 1010 MJ within the soil and water for the study area with an area of 163 km2 and a volume of 3.26 × 109 m3. It corresponds to an average energy density of 5.0 MJ/m3. The highest energy density of 16.5 MJ/m3 was found in the city center area and correlated well to increases in subsurface temperature. As expected, our model reacts sensitively to thickness changes in the geological layers and the unsaturated zone.

Ice-influenced hydrologic and hydrodynamic processes often cause floods in cold regions of the globe. These floods are typically associated with ice jams and can have negative socio-economic impacts, while their impacts on riverine ecosystems can be both detrimental and beneficial. Several methods have been proposed for constructing frequency distributions of ice-influenced annual peak stages where historical data are scarce, or for estimating future frequencies under different climate change scenarios. Such methods rely on historical discharge data, which are generally easier to obtain than peak stages. Future discharges can be simulated via hydrological models, driven by climate-model output. Binary sequences of historical flood/no-flood occurrences have been studied using logistic regression on physics-based explanatory variables or exclusively weather-controlled proxies, bypassing the hydrological modelling step in climate change projections. Herein, background material on relevant river ice processes is presented first, followed by descriptions of various proposed methods to quantify flood risk and assess their advantages and disadvantages. Discharge-based methods are more rigorous; however, projections of future flood risk can benefit from improved hydrological simulations of winter and spring discharges. The more convenient proxy-based regressions may not adequately reflect the controlling physics-based variables, while extrapolation of regression results to altered climatic conditions entails further uncertainty.

Ice-influenced hydrologic and hydrodynamic processes often cause floods in cold regions of the globe. These floods are typically associated with ice jams and can have negative socio-economic impacts, while their impacts on riverine ecosystems can be both detrimental and beneficial. Several methods have been proposed for constructing frequency distributions of ice-influenced annual peak stages where historical data are scarce, or for estimating future frequencies under different climate change scenarios. Such methods rely on historical discharge data, which are generally easier to obtain than peak stages. Future discharges can be simulated via hydrological models, driven by climate-model output. Binary sequences of historical flood/no-flood occurrences have been studied using logistic regression on physics-based explanatory variables or exclusively weather-controlled proxies, bypassing the hydrological modelling step in climate change projections. Herein, background material on relevant river ice processes is presented first, followed by descriptions of various proposed methods to quantify flood risk and assess their advantages and disadvantages. Discharge-based methods are more rigorous; however, projections of future flood risk can benefit from improved hydrological simulations of winter and spring discharges. The more convenient proxy-based regressions may not adequately reflect the controlling physics-based variables, while extrapolation of regression results to altered climatic conditions entails further uncertainty.

Leaders of Judaism, Christianity, and Islam have publicly advocated action to mitigate the adverse effects of human-forced climate change. Particularly prominent prior to, during, and after the 21st Conference of the Parties of the United Nations Framework Convention on Climate Change were Rabbi Arthur Waskow, Pope Francis, and Patriarch Bartholomew. Also prominent was a group of Islamic clerics, leaders of organizations, and scholars who collaborated in issuing a declaration on climate change three months prior to COP 21. Informed by the Earth sciences, these leaders shared their faith-based rationales for acting locally to internationally as indicated in the documents explored in this article. Examples of organizations motivated by their leaders’ faith perspectives demonstrate their readiness to act informed by scientists. To work effectively, these religious leaders and activist groups require well-substantiated conclusions from data collected to counter unsubstantiated claims by climate skeptics. Earth scientists will find among the religious leaders and groups allies in the quest for a flourishing planet.

Leaders of Judaism, Christianity, and Islam have publicly advocated action to mitigate the adverse effects of human-forced climate change. Particularly prominent prior to, during, and after the 21st Conference of the Parties of the United Nations Framework Convention on Climate Change were Rabbi Arthur Waskow, Pope Francis, and Patriarch Bartholomew. Also prominent was a group of Islamic clerics, leaders of organizations, and scholars who collaborated in issuing a declaration on climate change three months prior to COP 21. Informed by the Earth sciences, these leaders shared their faith-based rationales for acting locally to internationally as indicated in the documents explored in this article. Examples of organizations motivated by their leaders’ faith perspectives demonstrate their readiness to act informed by scientists. To work effectively, these religious leaders and activist groups require well-substantiated conclusions from data collected to counter unsubstantiated claims by climate skeptics. Earth scientists will find among the religious leaders and groups allies in the quest for a flourishing planet.

The northern Antarctic Peninsula was affected by a significant warming over the second half of the 20th century and the collapse of several ice shelves. Local climate conditions on James Ross Island on the northeastern coast can differ strongly from the main part of the Antarctic Peninsula. This paper reports the spatial and temporal variability of glacier surface velocities and the area of their outlets throughout James Ross Island, and evaluates potential relationships with atmospheric and oceanic conditions. Velocity estimates were retrieved from intensity feature tracking of scenes from satellite synthetic aperture radar sensors TerraSAR-X and TanDEM-X between 2014 and 2018, which were validated against ground observations. Calving front positions back to 1945 were used to calculate outlet area changes for the glaciers by using a common-box approach. The annual recession rates of almost all investigated glacier calving fronts decelerated for the time periods 2009–2014 and 2014–2018 in comparison to the period 1988–2009, but their velocity patterns differed. Analysis of atmospheric conditions failed to explain the different patterns in velocity and area changes. We suggest a strong influence from local bathymetric conditions. Future investigations of the oceanic conditions would be necessary for a profound understanding of the super-position of different influencing factors.