Principal investigator/work block leader in EU research project FP6: New Approaches to adaptive management under uncertainty, NEWATER 2006-09. Project leader GEUS.
We present the most recent Intergovernmental Panel on Climate Change Sixth Assessment Report (AR6... more We present the most recent Intergovernmental Panel on Climate Change Sixth Assessment Report (AR6) sea-level projections for four Danish cities (Aarhus, Copenhagen, Esbjerg and Hirtshals) under the Shared Socioeconomic Pathway (SSP) family of climate scenarios. These sea-level changes projected over the next century are up to an order of magnitude larger than those observed over the previous century. At these cities, year 2150 sea-level changes of between 29 and 55 cm are projected under the very low emissions scenario (SSP1-1.9), while changes of between 99 and 123 cm are projected under the very high emissions scenario (SSP5-8.5). These differences highlight the potentially significant impact of remaining opportunities for climate change mitigation. Due to this increase in mean sea level, the mean recurrence time between historically extreme events is expected to decrease. Under the very high emissions scenario, the historical 100-year storm flood event will become a 1- to 5-year ...
Although chalk aquifers are not too often associated with conduit flow, they are highly productiv... more Although chalk aquifers are not too often associated with conduit flow, they are highly productive groundwater systems and, like limestone aquifers, they can be vulnerable to contamination when exposed to land use activities. The Danish carbonate rocks are generally recognized to be highly fractured and covered by thick Quaternary sediments. Fissure flow is pronounced, occurring in the upper 50–100 m due to Pleistocene glaciations. According to recently published maps of the distribution of karst in Europe, Denmark has no karst. However, this study concludes that karstified chalk and limestone aquifers are an important source of freshwater in Denmark. Four national datasets on karst features, groundwater flow, groundwater chemistry, and fish ecological quality ratio (EQR) data now indicate more heterogeneous structures and preferential flow pathways in the chalk and limestone aquifers than had been conceptualized and modelled with a national water resources groundwater/surface-water...
Strengthening of capacity development in the area of disaster risk reduction and climate change a... more Strengthening of capacity development in the area of disaster risk reduction and climate change adaptation is focus of the coordinating action CATALYST and achieved by facilitating knowledge exchange and improving the science-application interface. A core activity of CATALYST is the convening of stakeholders including researchers and practitioners in a think tank process in four global regions, including the European Mediterranean, allowing virtual and face-to-face exchange on areas of concern such as data gaps and best practices. Explicitly including complexity and thus inherent uncertainty is crucial for appropriate and timely communication in climate adaptation. Predictions of future climate and patterns of vulnerability are highly uncertain and could lead to inaction in responding. Due to uncertainty associated to the long timeframes in adapting to climate change, appropriate adaptation strategies and planning may require iterative risk management strategies that allow continuou...
The paper analyses the national DK-model Hydrological Information and Prediction (HIP) system and... more The paper analyses the national DK-model Hydrological Information and Prediction (HIP) system and HIP portal viewed as a ‘Digital Twin’ and how the introduction of real-time dynamic updating of the DK-model HIP simulations can give room for plug-in sub-models with real-time boundary conditions made available from a HIP portal. The possible feedback to a national real-time risk knowledge base during extreme events (flooding and drought) is also discussed. Under climate change conditions, Denmark is likely to experience more rain in winter, more evapotranspiration in summer, intensified cloudbursts, drought, and sea level rise. These challenges have been addressed as part of the Joint Governmental Digitalization Strategy 2016-2020 for better use and sharing of public data about the terrain, water, and climate to support climate adaptation, water management, and disaster risk reduction. This initiative included the development of a new web-based data portal (HIP portal) developed by th...
Geological Survey of Denmark and Greenland Bulletin
The rapidly increasing impacts of climate change are likely to require changes in relevant instit... more The rapidly increasing impacts of climate change are likely to require changes in relevant institutions (IPCC 2012). An example is the growing need for immediate information on the entire water cycle (Fig. 1), with quantitative assessments of critical hydrological variables and flow interactions between different domains, e.g. atmosphere, plant-soil, surface water, groundwater and the sea, as they take place.
Background Abstraction of groundwater is a major stressor for terrestrial and aquatic ecosystems ... more Background Abstraction of groundwater is a major stressor for terrestrial and aquatic ecosystems especially in countries like Denmark where close to 99% of the water supply is based on groundwater. During the past decades overexploitation in Denmark and many other places has resulted in deterioration of aquifers and poor status of receiving ecosystems. Recently, the first River Basin Management Plans (EU Water Framework Directive) classified groundwater abstraction near the larger Danish cities to have severe sustainability problems due to over pumping. Criteria’s in the first round were related to median minimum flow reductions due to groundwater abstraction, typically with thresholds of max 5 % reduction (high status) and max 10-25 % reduction (good status), depending on rather old guidelines from 1979 by the Danish EPA for ecological goals for fish for various stream reaches (Henriksen and Refsgaard, 2013). Data bases with indicators for acceptable stream flow depletion for low f...
Groundwater stored in aquifers experiences a wide variety of natural, induced and/or anthropogeni... more Groundwater stored in aquifers experiences a wide variety of natural, induced and/or anthropogenic disturbances. Among them, groundwater extraction is the main disturbance that affects most of the aquifers in the world. Aquifer’s resilience, understood as the potential of the aquifer to sustain disturbances on the long term and to guarantee essential qualities and functions, provides a key tool when assessing sustainable groundwater management alternatives. The aim of this work is to illustrate an aquifer resilience framework that can support groundwater sustainable management. A theoretical framework is based on the identification of the key variables that parameterize the quantitative and qualitative responses of the groundwater flow system to pumping. An example from the literature based in Denmark is provided as an illustration of the proposed framework. The results show that long-term high quality data are essential to make a step further in aquifers dynamic responses. The quan...
ABSTRACT A catchment scale model MACRO-MIKE SHE is applied for simulating changes in pesticide co... more ABSTRACT A catchment scale model MACRO-MIKE SHE is applied for simulating changes in pesticide concentrations to the aquatic environment. The MACRO model is used to model the effect of changes in climate and pesticide management on pesticide leaching from the unsaturated zone and simulated percolation as well as solute flow is propagated to the MIKE SHE model. The intensity based bias correction method for converting from Regional Climate Modelling data to hydrological input data is the most appropriate method as it best reflects changes in rainfall intensity, and thus also in intensity for MACRO simulated percolation and solute flow. Results show that increased percolation simulated by the MACRO model and propagated to the MIKE SHE model nearly all ends up in increased drainage to the river. Further, pesticide solute entering the saturated zone (SZ) is mainly leaving SZ via drainage (85-94%), base flow (3.8-11.3%) and overland flow (0-3.1 %). Mean concentrations in groundwater (SZ) increase by 30-99% for one type of herbicide under future climatic conditions, whereas mean concentrations decrease for two other types by app. 93 and 91 % respectively. Future climatic conditions lead to higher concentrations in surface water for the first type of herbicides, but to decreased concentrations for the another type of herbicide and insecticide. It is overall concluded that an integrated catchment scale modeling approach is essential for pesticide fate simulation taking account of all possible hydrologic pathways.
ABSTRACT Hydrological models and environmental flow criteria (EFC) are important in water managem... more ABSTRACT Hydrological models and environmental flow criteria (EFC) are important in water management, but there are potential complications of combining the two. This study aimed to establish and demonstrate a framework for assessing a suitable combination of EFC and hydrological modelling. For this purpose, local expert knowledge on stream ecology is first used to establish a Critical-Flow-Calendar (CFC) depicting the typical periods for different types of stream flow being most critical to the selected ecological indicator. Then EFC are quantified for the period most critical to the specific case. Finally, the EFC are used to build objective functions for calibration of the hydrological model, and the hydrological model’s capability to simulate the critical stream flows are evaluated. The purpose is to tailor the hydrological model to simulate the critical stream flows and, if necessary, to select the EFC so that they can be simulated by the hydrological model. The utility of the method was tested for hydrological modelling of EFC in 49 catchments 25–763 km2 located at the island of Zealand in Denmark. Establishment of a CFC facilitated a constructive dialogue between ecologists and hydrologists which caused the hydrological modelling to focus on the most critical flows (low flows) and the summer low flow period. Seven different methods were applied for quantification of EFC using observations from 49 stream flow gauging stations. The Danish National Water Resource Model was then applied for hydrological modelling using (a) conventional model calibration focusing on annual water balance and (b) model calibration based on objective functions that were related to the CFC and EFC. Results showed that the 20% lowest stream flows were substantially overestimated (>100%) by the conventional hydrological model, whereas the low flow calibrated model performed better only substantially overestimating the 10% lowest stream flows. The relatively high simulation error for the lowest stream flows meant that the highest EFC was most suited to be combined with a hydrological model. To our knowledge this is the first study that tests a large scale hydrological model against EFC specifically for the period where the flow criteria are critical to the ecological indicator in question. In this case it is therefore recommended that EFC should be selected so that they can be simulated by a hydrological model and the hydrological model should be tailored to simulate the relevant flows.
Page 1. ENGAGING STAKEHOLDERS IN CONSTRUCTION AND VALIDATION OF BAYESIAN BELIEF NETWORK FOR GROUN... more Page 1. ENGAGING STAKEHOLDERS IN CONSTRUCTION AND VALIDATION OF BAYESIAN BELIEF NETWORK FOR GROUNDWATER PROTECTION Hans Jørgen Henriksena, Per Rasmussena, Gyrite Brandtb, Dorthe von Bülowb and Finn Verner Jensenc ...
We present the most recent Intergovernmental Panel on Climate Change Sixth Assessment Report (AR6... more We present the most recent Intergovernmental Panel on Climate Change Sixth Assessment Report (AR6) sea-level projections for four Danish cities (Aarhus, Copenhagen, Esbjerg and Hirtshals) under the Shared Socioeconomic Pathway (SSP) family of climate scenarios. These sea-level changes projected over the next century are up to an order of magnitude larger than those observed over the previous century. At these cities, year 2150 sea-level changes of between 29 and 55 cm are projected under the very low emissions scenario (SSP1-1.9), while changes of between 99 and 123 cm are projected under the very high emissions scenario (SSP5-8.5). These differences highlight the potentially significant impact of remaining opportunities for climate change mitigation. Due to this increase in mean sea level, the mean recurrence time between historically extreme events is expected to decrease. Under the very high emissions scenario, the historical 100-year storm flood event will become a 1- to 5-year ...
Although chalk aquifers are not too often associated with conduit flow, they are highly productiv... more Although chalk aquifers are not too often associated with conduit flow, they are highly productive groundwater systems and, like limestone aquifers, they can be vulnerable to contamination when exposed to land use activities. The Danish carbonate rocks are generally recognized to be highly fractured and covered by thick Quaternary sediments. Fissure flow is pronounced, occurring in the upper 50–100 m due to Pleistocene glaciations. According to recently published maps of the distribution of karst in Europe, Denmark has no karst. However, this study concludes that karstified chalk and limestone aquifers are an important source of freshwater in Denmark. Four national datasets on karst features, groundwater flow, groundwater chemistry, and fish ecological quality ratio (EQR) data now indicate more heterogeneous structures and preferential flow pathways in the chalk and limestone aquifers than had been conceptualized and modelled with a national water resources groundwater/surface-water...
Strengthening of capacity development in the area of disaster risk reduction and climate change a... more Strengthening of capacity development in the area of disaster risk reduction and climate change adaptation is focus of the coordinating action CATALYST and achieved by facilitating knowledge exchange and improving the science-application interface. A core activity of CATALYST is the convening of stakeholders including researchers and practitioners in a think tank process in four global regions, including the European Mediterranean, allowing virtual and face-to-face exchange on areas of concern such as data gaps and best practices. Explicitly including complexity and thus inherent uncertainty is crucial for appropriate and timely communication in climate adaptation. Predictions of future climate and patterns of vulnerability are highly uncertain and could lead to inaction in responding. Due to uncertainty associated to the long timeframes in adapting to climate change, appropriate adaptation strategies and planning may require iterative risk management strategies that allow continuou...
The paper analyses the national DK-model Hydrological Information and Prediction (HIP) system and... more The paper analyses the national DK-model Hydrological Information and Prediction (HIP) system and HIP portal viewed as a ‘Digital Twin’ and how the introduction of real-time dynamic updating of the DK-model HIP simulations can give room for plug-in sub-models with real-time boundary conditions made available from a HIP portal. The possible feedback to a national real-time risk knowledge base during extreme events (flooding and drought) is also discussed. Under climate change conditions, Denmark is likely to experience more rain in winter, more evapotranspiration in summer, intensified cloudbursts, drought, and sea level rise. These challenges have been addressed as part of the Joint Governmental Digitalization Strategy 2016-2020 for better use and sharing of public data about the terrain, water, and climate to support climate adaptation, water management, and disaster risk reduction. This initiative included the development of a new web-based data portal (HIP portal) developed by th...
Geological Survey of Denmark and Greenland Bulletin
The rapidly increasing impacts of climate change are likely to require changes in relevant instit... more The rapidly increasing impacts of climate change are likely to require changes in relevant institutions (IPCC 2012). An example is the growing need for immediate information on the entire water cycle (Fig. 1), with quantitative assessments of critical hydrological variables and flow interactions between different domains, e.g. atmosphere, plant-soil, surface water, groundwater and the sea, as they take place.
Background Abstraction of groundwater is a major stressor for terrestrial and aquatic ecosystems ... more Background Abstraction of groundwater is a major stressor for terrestrial and aquatic ecosystems especially in countries like Denmark where close to 99% of the water supply is based on groundwater. During the past decades overexploitation in Denmark and many other places has resulted in deterioration of aquifers and poor status of receiving ecosystems. Recently, the first River Basin Management Plans (EU Water Framework Directive) classified groundwater abstraction near the larger Danish cities to have severe sustainability problems due to over pumping. Criteria’s in the first round were related to median minimum flow reductions due to groundwater abstraction, typically with thresholds of max 5 % reduction (high status) and max 10-25 % reduction (good status), depending on rather old guidelines from 1979 by the Danish EPA for ecological goals for fish for various stream reaches (Henriksen and Refsgaard, 2013). Data bases with indicators for acceptable stream flow depletion for low f...
Groundwater stored in aquifers experiences a wide variety of natural, induced and/or anthropogeni... more Groundwater stored in aquifers experiences a wide variety of natural, induced and/or anthropogenic disturbances. Among them, groundwater extraction is the main disturbance that affects most of the aquifers in the world. Aquifer’s resilience, understood as the potential of the aquifer to sustain disturbances on the long term and to guarantee essential qualities and functions, provides a key tool when assessing sustainable groundwater management alternatives. The aim of this work is to illustrate an aquifer resilience framework that can support groundwater sustainable management. A theoretical framework is based on the identification of the key variables that parameterize the quantitative and qualitative responses of the groundwater flow system to pumping. An example from the literature based in Denmark is provided as an illustration of the proposed framework. The results show that long-term high quality data are essential to make a step further in aquifers dynamic responses. The quan...
ABSTRACT A catchment scale model MACRO-MIKE SHE is applied for simulating changes in pesticide co... more ABSTRACT A catchment scale model MACRO-MIKE SHE is applied for simulating changes in pesticide concentrations to the aquatic environment. The MACRO model is used to model the effect of changes in climate and pesticide management on pesticide leaching from the unsaturated zone and simulated percolation as well as solute flow is propagated to the MIKE SHE model. The intensity based bias correction method for converting from Regional Climate Modelling data to hydrological input data is the most appropriate method as it best reflects changes in rainfall intensity, and thus also in intensity for MACRO simulated percolation and solute flow. Results show that increased percolation simulated by the MACRO model and propagated to the MIKE SHE model nearly all ends up in increased drainage to the river. Further, pesticide solute entering the saturated zone (SZ) is mainly leaving SZ via drainage (85-94%), base flow (3.8-11.3%) and overland flow (0-3.1 %). Mean concentrations in groundwater (SZ) increase by 30-99% for one type of herbicide under future climatic conditions, whereas mean concentrations decrease for two other types by app. 93 and 91 % respectively. Future climatic conditions lead to higher concentrations in surface water for the first type of herbicides, but to decreased concentrations for the another type of herbicide and insecticide. It is overall concluded that an integrated catchment scale modeling approach is essential for pesticide fate simulation taking account of all possible hydrologic pathways.
ABSTRACT Hydrological models and environmental flow criteria (EFC) are important in water managem... more ABSTRACT Hydrological models and environmental flow criteria (EFC) are important in water management, but there are potential complications of combining the two. This study aimed to establish and demonstrate a framework for assessing a suitable combination of EFC and hydrological modelling. For this purpose, local expert knowledge on stream ecology is first used to establish a Critical-Flow-Calendar (CFC) depicting the typical periods for different types of stream flow being most critical to the selected ecological indicator. Then EFC are quantified for the period most critical to the specific case. Finally, the EFC are used to build objective functions for calibration of the hydrological model, and the hydrological model’s capability to simulate the critical stream flows are evaluated. The purpose is to tailor the hydrological model to simulate the critical stream flows and, if necessary, to select the EFC so that they can be simulated by the hydrological model. The utility of the method was tested for hydrological modelling of EFC in 49 catchments 25–763 km2 located at the island of Zealand in Denmark. Establishment of a CFC facilitated a constructive dialogue between ecologists and hydrologists which caused the hydrological modelling to focus on the most critical flows (low flows) and the summer low flow period. Seven different methods were applied for quantification of EFC using observations from 49 stream flow gauging stations. The Danish National Water Resource Model was then applied for hydrological modelling using (a) conventional model calibration focusing on annual water balance and (b) model calibration based on objective functions that were related to the CFC and EFC. Results showed that the 20% lowest stream flows were substantially overestimated (>100%) by the conventional hydrological model, whereas the low flow calibrated model performed better only substantially overestimating the 10% lowest stream flows. The relatively high simulation error for the lowest stream flows meant that the highest EFC was most suited to be combined with a hydrological model. To our knowledge this is the first study that tests a large scale hydrological model against EFC specifically for the period where the flow criteria are critical to the ecological indicator in question. In this case it is therefore recommended that EFC should be selected so that they can be simulated by a hydrological model and the hydrological model should be tailored to simulate the relevant flows.
Page 1. ENGAGING STAKEHOLDERS IN CONSTRUCTION AND VALIDATION OF BAYESIAN BELIEF NETWORK FOR GROUN... more Page 1. ENGAGING STAKEHOLDERS IN CONSTRUCTION AND VALIDATION OF BAYESIAN BELIEF NETWORK FOR GROUNDWATER PROTECTION Hans Jørgen Henriksena, Per Rasmussena, Gyrite Brandtb, Dorthe von Bülowb and Finn Verner Jensenc ...
Uploads
Papers