Atle Harby - Profile on Academia.edu (original) (raw)
Papers by Atle Harby
Environmental flows from dams: the water framework directive
Proceedings of the Institution of Civil Engineers, Mar 1, 2009
G-res tool modelling database
This database regroups GHG measurements from freshwater reservoirs. It also includes other reserv... more This database regroups GHG measurements from freshwater reservoirs. It also includes other reservoir and catchment characteristics. This database was used to develop the G-res Tool models. Please see Prairie et al 2017 for more details and for calculations (Prairie, Y. T., Alm, J., Harby, A., Mercier-Blais, S., & Nahas, R. (2017). Technical documentation, UNESCO/IHA research project on the GHG status of freshwater reservoirs. Available at :https://g-res.hydropower.org/guidance-documents/)
The GHG Reservoir Tool (Gres) Technical documentation : UNESCO/IHA research project on the GHG status of freshwater reservoirs : Version 1.1
201
European aquatic modelling network
River Research and Applications, 2007
Simulations of environmental impacts and hydropower production at a refurbished hydropower system in Norway
It is well known that hydropower may have a strong impact on the aquatic environment, and both ne... more It is well known that hydropower may have a strong impact on the aquatic environment, and both new and existing hydropower need to mitigate negative environmental impacts. Hydrological as well as market and grid situations are changing, leading to a need for redesign of many hydropower facilities. Further, modern requirements to include environmental and social aspects of hydropower redesign , re-licensing and expansions will lead to new solutions. At the same time the environmental consequences need to be carefully evaluated and mitigated. Impacts on fish species receives much attention, and the EU-funded research project FIThydro (Grant Agreement number 727830, duration 2016-2020) is focusing on developing methods, tools and devices for solutions to improve conditions for fish and at the same time maintaining the hydropower production. This paper describes methods to find costeffective mitigation measures to inform decision support for improving fish conditions in hydropower rivers. The aim of optimizing hydropower as well as fish production with the most cost-effective combination of mitigation measures and environmental flows will also be demonstrated in several examples. FIThydro is also developing a Decision Support System (DSS). The proposed DSS framework is aimed at regulators and operators and orientated around a single, risk-based, planning structure for both new and existing hydropower schemes. The DSS will be linked to the internet-based solution for mitigation measures, and it will guide the user directly towards finding the most cost-effective mitigation measure.
The net GHG emissions of the Three Gorges Reservoir in China: II. Post-impoundment GHG inventories and full-scale synthesis
Journal of Cleaner Production, Dec 1, 2020
Abstract Greenhouse gas (GHG) emissions are receiving worldwide attention and concern over the pa... more Abstract Greenhouse gas (GHG) emissions are receiving worldwide attention and concern over the past decades. However, the net change of GHG emissions due to reservoir creation is not well reported. The objective of the study was to evaluate the net GHG emissions of the Three Gorges Reservoir (TGR), the largest reservoir in volume and installed capacity in China. Here, we provide the first full-scale synthesis of GHG emissions in the TGR. Data from two large sampling campaigns between 2010 and 2017 showed that the post-impoundment GHG emissions of the TGR were 1.36 ± 0.16 × 106 tCO2eq yr−1. A majority of GHGs (30%–70%) are emitted from air-water diffusive pathway in the main stem. Anthropogenic carbon and nutrients loads from the reservoir vicinity did not significantly contribute to the post-impoundment GHG emissions. Reservoir GHG emissions were mainly regulated by annual inflow. Subtracting pre-impoundment GHG emissions from post-impoundment emissions, the net GHG emissions of the TGR in our sampling campaigns were 10.41 ± 1.28 × 105 tCO2eq yr−1. In terms of CO2 equivalents per unit of hydropower production in the same years, they were 11.8 ± 1.8 gCO2eq⋅kWh−1. Mass budget analysis showed that flooding and decomposition of organic matter in flooded land could only explain 19.9% of reservoir net GHG emissions. A large proportion of the net GHG emissions needs further study to be quantitatively identified. In addition, our study elaborated the current limitations and further research needs in evaluation of carbon footprints of reservoir creation.
Testing of the river system simulator on the river system of Stjoerdalen. Simulation of floods in the lower parts of the Stjoerdalselva with HEC-2
Testing of the river system simulator on the Stjoerdalen river system. Simulation of hydropower production and control using VANSIMPLAN
Typologi i regulerte vassdrag i Norge : forslag til typologisystem til anvendelse for forskning innenfor FME HydroCEN
12, 2017
User guidelines for the Earth Engine functionality, UNESCO/IHA research project on the GHG status of freshwater reservoirs
The River System Simulator
Application and Comparison of Computer Models for Quantifying Impacts of River Regulation on Fish Habitat
Corrigendum to “The net GHG emissions of the Three Gorges Reservoir in China: II. post-impoundment GHG inventories and full-scale synthesis” [J. Cleaner Prod. 277, 123961]
Journal of Cleaner Production, Feb 1, 2021
River Research and Applications, Jul 12, 2011
Hydropower produces 99% of the electricity in Norway and a large number of rivers are regulated. ... more Hydropower produces 99% of the electricity in Norway and a large number of rivers are regulated. Currently static minimum flow regimes are used as a mitigation measure for most of these developments, usually having fixed values for winter and summer flow. Improved knowledge on the importance of variability in flow regimes has lead to research on alternative solutions to the static minimum flow regimes. This paper describes the development of an environmental flow regime that is designed to follow the variation in natural inflow. The flow regime is designed using an adaptation of the Building Block Methodology, and linked to high, normal and low natural flow conditions. The work is focused on the river Daleelva in western Norway which were Atlantic salmon is the key species. The paper also describes how the variable environmental flow regime can be implemented in practice in light of current Norwegian legislation.
A mesohabitat method used to assess minimum flow changes and impacts on the invertebrate and fish fauna in the Rhône River, France
River Research and Applications, 2007
At the 8 km bypass section of Chautagne in the Rhône River, most of the flow is diverted due to h... more At the 8 km bypass section of Chautagne in the Rhône River, most of the flow is diverted due to hydropower production. The environmental flow to the bypass section of the Rhône River was increased from 10 m3 s−1 (winter) and 20 m3 s−1 (summer) to 50 m3 s−1 (winter) and 70 m3 s−1 (summer) in July 2004. A Norwegian mesohabitat method of classifying the river into physical mesoscale morphological (mesohabitat) classes by visual observation was applied at 10 and 70 m3 s−1. The results show that the dominating classes at both flows are deep and low velocity pools, but a higher physical diversity occurs at 70 m3 s−1, quantified by indices from Simpson (1949) and Shannon and Weaver (1962). In total, 6 per cent of the depth measurements and 0.3 per cent of the velocity measurements were outside the expected range at low flow. At high flow, 16.2 per cent of the depth measurements and 19.6 per cent of the velocity measurements were outside the expected range. The change in mesohabitats gives impacts on the composition and abundance of fish and invertebrates. Rheophilic taxa are favoured by the increased flow while more limnophilic species will find less amount of suitable habitat at 70 m3 s−1. Other studies show that population densities of grayling, brown trout, nase and dace have decreased greatly and become endangered since hydropower development, while densities of gudgeon, minnow and stone loach have increased. Fish habitat preferences from Lamouroux et al. (1999a) and Mallet et al. (2000) were used. Most of the endangered species need high velocity mesohabitats and both high and low depths during all life stages. The increase of such mesohabitat proportions at 70 m3 s−1 indicates that their population should recover soon. The method may be a useful tool to compare different flow situations and their impact on the invertebrate and fish population structure even in large rivers. Copyright © 2007 John Wiley & Sons, Ltd.
Ecosystems, Nov 8, 2017
Freshwater reservoirs are a known source of greenhouse gas (GHG) to the atmosphere, but their qua... more Freshwater reservoirs are a known source of greenhouse gas (GHG) to the atmosphere, but their quantitative significance is still only loosely constrained. Although part of this uncertainty can be attributed to the difficulties in measuring highly variable fluxes, it is also the result of a lack of a clear accounting methodology, particularly about what constitutes new emissions and potential new sinks. In this paper, we review the main processes involved in the generation of GHG in reservoir systems and propose a simple approach to quantify the reservoir GHG footprint in terms of the net changes in GHG fluxes to the atmosphere induced by damming, that is, 'what the atmosphere sees.' The approach takes into account the pre-impoundment GHG balance of the landscape, the temporal evolution of reservoir GHG emission profile as well as the natural emissions that are displaced to or away from the reservoir site resulting from hydrological and other changes. It also clarifies the portion of the reservoir carbon burial that can potentially be considered an offset to GHG emissions.
Testing of the river system simulator on reference rivers. Main report
Habitat modelling with the watercourse simulator in Maana - data report
Flomdempingstjenester i utvidet miljødesign - Beskrivelse og uttesting av system for klassifisering av flomdempingspotensial i regulerte vassdrag
Sammendrag: Hydrocen arbeidspakke 4.3 jobber med å utvide miljødesignkonseptet som ble etablert i... more Sammendrag: Hydrocen arbeidspakke 4.3 jobber med å utvide miljødesignkonseptet som ble etablert i forskningssenteret CEDREN. Forskjellige nye aspekter som er viktige for en helhetlig vurdering av positive og negative konsekvenser og tjenester av vannkraft skal legges til, og blant disse er temaet flomdempingstjenester. Denne rapporten går gjennom metodikken vi har utviklet for klassifisering av flomdempingstjenester fra vannkraftmagasin. Metodikken viser potensiell flomdemping på et oversiktsnivå ved å analysere lett tilgjengelige data om magasinstørrelse, årstilsig, typisk magasinfylling over året, tappekapasitet og forholdet mellom reguleringsgrad og demping av flomtopp. Metodikken er ment for system med flere magasin, og en klassifisering vil bli gitt for hvert enkelt magasin sett i sammenheng med resten av systemet. Systemet som helhet blir også klassifisert. Metodikken er laget slik at det er enkelt å se på hvordan endringer i systemet påvirker flomdempingstjenester. Med hjelp fra kraftselskapet Hydro har metodikken blitt anvendt i fem testvassdrag, og resultatene har blitt diskutert med de som har godt kjennskap til vassdragene. Metodikken har blitt forbedret basert på svakheter som ble oppdaget under uttesting og forslag fra diskusjoner. Resultater og kommentarer fra forfatterne er presentert i rapporten, i tillegg til kommentarer om hvor rimelig klassifiseringen virker og hvilke konklusjoner som kan dras. Basert på kunnskap om vassdragene fremstår klassifiseringene som rimelige, og metodikken kan ha nytteverdi for en grov analyse av konsekvenser av endringer i vassdraget
Environmental flows from dams: the water framework directive
Proceedings of the Institution of Civil Engineers, Mar 1, 2009
G-res tool modelling database
This database regroups GHG measurements from freshwater reservoirs. It also includes other reserv... more This database regroups GHG measurements from freshwater reservoirs. It also includes other reservoir and catchment characteristics. This database was used to develop the G-res Tool models. Please see Prairie et al 2017 for more details and for calculations (Prairie, Y. T., Alm, J., Harby, A., Mercier-Blais, S., & Nahas, R. (2017). Technical documentation, UNESCO/IHA research project on the GHG status of freshwater reservoirs. Available at :https://g-res.hydropower.org/guidance-documents/)
The GHG Reservoir Tool (Gres) Technical documentation : UNESCO/IHA research project on the GHG status of freshwater reservoirs : Version 1.1
201
European aquatic modelling network
River Research and Applications, 2007
Simulations of environmental impacts and hydropower production at a refurbished hydropower system in Norway
It is well known that hydropower may have a strong impact on the aquatic environment, and both ne... more It is well known that hydropower may have a strong impact on the aquatic environment, and both new and existing hydropower need to mitigate negative environmental impacts. Hydrological as well as market and grid situations are changing, leading to a need for redesign of many hydropower facilities. Further, modern requirements to include environmental and social aspects of hydropower redesign , re-licensing and expansions will lead to new solutions. At the same time the environmental consequences need to be carefully evaluated and mitigated. Impacts on fish species receives much attention, and the EU-funded research project FIThydro (Grant Agreement number 727830, duration 2016-2020) is focusing on developing methods, tools and devices for solutions to improve conditions for fish and at the same time maintaining the hydropower production. This paper describes methods to find costeffective mitigation measures to inform decision support for improving fish conditions in hydropower rivers. The aim of optimizing hydropower as well as fish production with the most cost-effective combination of mitigation measures and environmental flows will also be demonstrated in several examples. FIThydro is also developing a Decision Support System (DSS). The proposed DSS framework is aimed at regulators and operators and orientated around a single, risk-based, planning structure for both new and existing hydropower schemes. The DSS will be linked to the internet-based solution for mitigation measures, and it will guide the user directly towards finding the most cost-effective mitigation measure.
The net GHG emissions of the Three Gorges Reservoir in China: II. Post-impoundment GHG inventories and full-scale synthesis
Journal of Cleaner Production, Dec 1, 2020
Abstract Greenhouse gas (GHG) emissions are receiving worldwide attention and concern over the pa... more Abstract Greenhouse gas (GHG) emissions are receiving worldwide attention and concern over the past decades. However, the net change of GHG emissions due to reservoir creation is not well reported. The objective of the study was to evaluate the net GHG emissions of the Three Gorges Reservoir (TGR), the largest reservoir in volume and installed capacity in China. Here, we provide the first full-scale synthesis of GHG emissions in the TGR. Data from two large sampling campaigns between 2010 and 2017 showed that the post-impoundment GHG emissions of the TGR were 1.36 ± 0.16 × 106 tCO2eq yr−1. A majority of GHGs (30%–70%) are emitted from air-water diffusive pathway in the main stem. Anthropogenic carbon and nutrients loads from the reservoir vicinity did not significantly contribute to the post-impoundment GHG emissions. Reservoir GHG emissions were mainly regulated by annual inflow. Subtracting pre-impoundment GHG emissions from post-impoundment emissions, the net GHG emissions of the TGR in our sampling campaigns were 10.41 ± 1.28 × 105 tCO2eq yr−1. In terms of CO2 equivalents per unit of hydropower production in the same years, they were 11.8 ± 1.8 gCO2eq⋅kWh−1. Mass budget analysis showed that flooding and decomposition of organic matter in flooded land could only explain 19.9% of reservoir net GHG emissions. A large proportion of the net GHG emissions needs further study to be quantitatively identified. In addition, our study elaborated the current limitations and further research needs in evaluation of carbon footprints of reservoir creation.
Testing of the river system simulator on the river system of Stjoerdalen. Simulation of floods in the lower parts of the Stjoerdalselva with HEC-2
Testing of the river system simulator on the Stjoerdalen river system. Simulation of hydropower production and control using VANSIMPLAN
Typologi i regulerte vassdrag i Norge : forslag til typologisystem til anvendelse for forskning innenfor FME HydroCEN
12, 2017
User guidelines for the Earth Engine functionality, UNESCO/IHA research project on the GHG status of freshwater reservoirs
The River System Simulator
Application and Comparison of Computer Models for Quantifying Impacts of River Regulation on Fish Habitat
Corrigendum to “The net GHG emissions of the Three Gorges Reservoir in China: II. post-impoundment GHG inventories and full-scale synthesis” [J. Cleaner Prod. 277, 123961]
Journal of Cleaner Production, Feb 1, 2021
River Research and Applications, Jul 12, 2011
Hydropower produces 99% of the electricity in Norway and a large number of rivers are regulated. ... more Hydropower produces 99% of the electricity in Norway and a large number of rivers are regulated. Currently static minimum flow regimes are used as a mitigation measure for most of these developments, usually having fixed values for winter and summer flow. Improved knowledge on the importance of variability in flow regimes has lead to research on alternative solutions to the static minimum flow regimes. This paper describes the development of an environmental flow regime that is designed to follow the variation in natural inflow. The flow regime is designed using an adaptation of the Building Block Methodology, and linked to high, normal and low natural flow conditions. The work is focused on the river Daleelva in western Norway which were Atlantic salmon is the key species. The paper also describes how the variable environmental flow regime can be implemented in practice in light of current Norwegian legislation.
A mesohabitat method used to assess minimum flow changes and impacts on the invertebrate and fish fauna in the Rhône River, France
River Research and Applications, 2007
At the 8 km bypass section of Chautagne in the Rhône River, most of the flow is diverted due to h... more At the 8 km bypass section of Chautagne in the Rhône River, most of the flow is diverted due to hydropower production. The environmental flow to the bypass section of the Rhône River was increased from 10 m3 s−1 (winter) and 20 m3 s−1 (summer) to 50 m3 s−1 (winter) and 70 m3 s−1 (summer) in July 2004. A Norwegian mesohabitat method of classifying the river into physical mesoscale morphological (mesohabitat) classes by visual observation was applied at 10 and 70 m3 s−1. The results show that the dominating classes at both flows are deep and low velocity pools, but a higher physical diversity occurs at 70 m3 s−1, quantified by indices from Simpson (1949) and Shannon and Weaver (1962). In total, 6 per cent of the depth measurements and 0.3 per cent of the velocity measurements were outside the expected range at low flow. At high flow, 16.2 per cent of the depth measurements and 19.6 per cent of the velocity measurements were outside the expected range. The change in mesohabitats gives impacts on the composition and abundance of fish and invertebrates. Rheophilic taxa are favoured by the increased flow while more limnophilic species will find less amount of suitable habitat at 70 m3 s−1. Other studies show that population densities of grayling, brown trout, nase and dace have decreased greatly and become endangered since hydropower development, while densities of gudgeon, minnow and stone loach have increased. Fish habitat preferences from Lamouroux et al. (1999a) and Mallet et al. (2000) were used. Most of the endangered species need high velocity mesohabitats and both high and low depths during all life stages. The increase of such mesohabitat proportions at 70 m3 s−1 indicates that their population should recover soon. The method may be a useful tool to compare different flow situations and their impact on the invertebrate and fish population structure even in large rivers. Copyright © 2007 John Wiley & Sons, Ltd.
Ecosystems, Nov 8, 2017
Freshwater reservoirs are a known source of greenhouse gas (GHG) to the atmosphere, but their qua... more Freshwater reservoirs are a known source of greenhouse gas (GHG) to the atmosphere, but their quantitative significance is still only loosely constrained. Although part of this uncertainty can be attributed to the difficulties in measuring highly variable fluxes, it is also the result of a lack of a clear accounting methodology, particularly about what constitutes new emissions and potential new sinks. In this paper, we review the main processes involved in the generation of GHG in reservoir systems and propose a simple approach to quantify the reservoir GHG footprint in terms of the net changes in GHG fluxes to the atmosphere induced by damming, that is, 'what the atmosphere sees.' The approach takes into account the pre-impoundment GHG balance of the landscape, the temporal evolution of reservoir GHG emission profile as well as the natural emissions that are displaced to or away from the reservoir site resulting from hydrological and other changes. It also clarifies the portion of the reservoir carbon burial that can potentially be considered an offset to GHG emissions.
Testing of the river system simulator on reference rivers. Main report
Habitat modelling with the watercourse simulator in Maana - data report
Flomdempingstjenester i utvidet miljødesign - Beskrivelse og uttesting av system for klassifisering av flomdempingspotensial i regulerte vassdrag
Sammendrag: Hydrocen arbeidspakke 4.3 jobber med å utvide miljødesignkonseptet som ble etablert i... more Sammendrag: Hydrocen arbeidspakke 4.3 jobber med å utvide miljødesignkonseptet som ble etablert i forskningssenteret CEDREN. Forskjellige nye aspekter som er viktige for en helhetlig vurdering av positive og negative konsekvenser og tjenester av vannkraft skal legges til, og blant disse er temaet flomdempingstjenester. Denne rapporten går gjennom metodikken vi har utviklet for klassifisering av flomdempingstjenester fra vannkraftmagasin. Metodikken viser potensiell flomdemping på et oversiktsnivå ved å analysere lett tilgjengelige data om magasinstørrelse, årstilsig, typisk magasinfylling over året, tappekapasitet og forholdet mellom reguleringsgrad og demping av flomtopp. Metodikken er ment for system med flere magasin, og en klassifisering vil bli gitt for hvert enkelt magasin sett i sammenheng med resten av systemet. Systemet som helhet blir også klassifisert. Metodikken er laget slik at det er enkelt å se på hvordan endringer i systemet påvirker flomdempingstjenester. Med hjelp fra kraftselskapet Hydro har metodikken blitt anvendt i fem testvassdrag, og resultatene har blitt diskutert med de som har godt kjennskap til vassdragene. Metodikken har blitt forbedret basert på svakheter som ble oppdaget under uttesting og forslag fra diskusjoner. Resultater og kommentarer fra forfatterne er presentert i rapporten, i tillegg til kommentarer om hvor rimelig klassifiseringen virker og hvilke konklusjoner som kan dras. Basert på kunnskap om vassdragene fremstår klassifiseringene som rimelige, og metodikken kan ha nytteverdi for en grov analyse av konsekvenser av endringer i vassdraget