Norman Dreier - Academia.edu (original) (raw)

Papers by Norman Dreier

Research paper thumbnail of Future Changes in Wave Conditions at the German Baltic Sea Coast Based on a Hybrid Approach Using an Ensemble of Regional Climate Change Projections

Water

In this study, the projected future long-term changes of the local wave conditions at the German ... more In this study, the projected future long-term changes of the local wave conditions at the German Baltic Sea coast over the course of the 21st century are analyzed and assessed with special focus on model agreement, statistical significance and ranges/spread of the results. An ensemble of new regional climate model (RCM) simulations with the RCM REMO for three RCP forcing scenarios was used as input data. The outstanding feature of the simulations is that the data are available with a high horizontal resolution and at hourly timesteps which is a high temporal resolution and beneficial for the wind–wave modelling. A new data interface between RCM output data and wind–wave modelling has been developed. Suitable spatial aggregation methods of the RCM wind data have been tested and used to generate input for the calculation of waves at quasi deep-water conditions and at a mean water level with a hybrid approach that enables the fast compilation of future long-term time series of signific...

Research paper thumbnail of Modeling eelgrass spatial response to nutrient abatement measures in a changing climate

Ambio

For many coastal areas including the Baltic Sea, ambitious nutrient abatement goals have been set... more For many coastal areas including the Baltic Sea, ambitious nutrient abatement goals have been set to curb eutrophication, but benefits of such measures were normally not studied in light of anticipated climate change. To project the likely responses of nutrient abatement on eelgrass (Zostera marina), we coupled a species distribution model with a biogeochemical model, obtaining future water turbidity, and a wave model for predicting the future hydrodynamics in the coastal area. Using this, eelgrass distribution was modeled for different combinations of nutrient scenarios and future wind fields. We are the first to demonstrate that while under a business as usual scenario overall eelgrass area will not recover, nutrient reductions that fulfill the Helsinki Commission’s Baltic Sea Action Plan (BSAP) are likely to lead to a substantial areal expansion of eelgrass coverage, primarily at the current distribution’s lower depth limits, thereby overcompensating losses in shallow areas cause...

Research paper thumbnail of Long-term Changes of Waves at the German Baltic Sea Coast: Are There Trends from the Past?

Journal of Coastal Research

Research paper thumbnail of Operational wave forecast in the German Bight as part of a sensor- and risk based early warning system

Journal of Coastal Research

BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

Research paper thumbnail of On the Long-term Changes of Extreme Wave Heights at the German Baltic Sea Coast

Journal of Coastal Research

BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

Research paper thumbnail of Changes of 21 st Century's average and extreme wave conditions at the German Baltic Sea Coast due to global climate change

Journal of Coastal Research, 2013

ABSTRACT On the basis of hourly simulated wind data from a regional circulation model (Cosmo-CLM)... more ABSTRACT On the basis of hourly simulated wind data from a regional circulation model (Cosmo-CLM) long-term time series (1960-2100) of wave parameters were compiled for two of the SRES scenarios A1B, B1 at three locations along the German Baltic Sea Coast. The time series of wave parameters were calculated with the help of statistical correlations between observed wind and wave data, which were derived for the three locations in the study area. Furthermore, we applied a wave model for the Western Baltic Sea to correct some of the calculated wave information. The key findings of this study are that: (i) significant changes of average wind conditions can directly be linked to significant changes of the average wave conditions, (ii) a spatial pattern for the changes of average wave conditions can be found, (iii) no general trend can be found for the changes of extreme wave conditions. Comparisons of wind conditions, as simulated by the regional circulation model, for the past and the future are showing two main changes: (a) increases of average wind velocities to the end of the 21st century up to +4% and (b) more wind events from westerly and less events from easterly directions. The changes of the average wind velocities are resulting in increases of the average significant wave heights at westerly wind exposed locations up to +7% and small decreases of the average significant wave heights at easterly wind exposed locations. The future changes of the wave directions, with more wave events from W-NW and fewer events from N-NE, can be connected to the future changes of wind directions. Analyses of extreme wave heights with a return period of 200 years are showing both increasing and decreasing changes of up/down to +/-14%. At one location of the study area (Warnemunde) a slight increasing trend for the change of extreme wave heights to the end of the 21st century exists.

Research paper thumbnail of Statistical methods for the analysis of simulated and observed climate data, applied in projects and institutions dealing with climate change impact and adaptation., 135 S

Research paper thumbnail of Statistische Verfahren zur Auswertung von Klimadaten aus Modell und Beobachtung, eingesetzt in Projekten und Institutionen, die sich mit Klimafolgen und Anpassung befassen

Häufigkeit von Frosttagen nach Vegetationsbeginn/ zeitlicher Abstand von Terminen des letzten Fro... more Häufigkeit von Frosttagen nach Vegetationsbeginn/ zeitlicher Abstand von Terminen des letzten Frosttages und des Vegetationsbeginns .

Research paper thumbnail of Assessment of Future Wave Climate on basis of Wind-Wave- Correlations and Climate Change Scenarios

Consequences resulting from future climate change may be one of the most severe threats for peopl... more Consequences resulting from future climate change may be one of the most severe threats for people and economies in many countries of the world. With respect to coastal protection, the resulting changed hydrodynamic impacts are discussed globally. At present, IPCC (2007) is estimating a world-wide average sea level rise of less than 1.0m within the 21st century. Other sources (e.g. Rahmstorf & Schellnhuber, 2007) which are taking into account possible melting of the two main continental ice covers (Greenland and Antarctica), estimate significantly higher values especially over long periods. Besides the problem of sea level rise, also possible general changes of the local wave conditions are described. The model results indicate a small increase of the overall wave energy input for the future and a more significant change in the wave directions where westerly wave conditions may increase by 3.5% compared to the actual conditions.

Research paper thumbnail of The Use of a Regional Climate- and Wave Model for the Assessment of Changes of the Future Wave Climate in the Western Baltic Sea

Coastal Engineering Proceedings, 2014

On the basis of hourly simulated wind data from a regional circulation model (Cosmo-CLM) wave con... more On the basis of hourly simulated wind data from a regional circulation model (Cosmo-CLM) wave conditions from 1960 to 2100 are calculated for two realisations each of the global emission scenarios A1B and B1 using a numerical wave model for the area of the Western Baltic Sea. Comparisons of the 30 years averages of the wave conditions between the future and the past show that the changes of the average wave conditions can be directly linked to the changes of the average wind conditions. The changes of the average wave conditions and extreme wave events are characterised by high spatial and annual variability. In addition the changes depend on the time period of the comparison, the global emission scenario and the realisation of the climate model run. The bandwidth of the changes is moreover affected by the approach for the calculation of the wave conditions. A significant climate change signal of the average wave conditions is found at westerly wind exposed locations with predominant higher values of the average significant wave heights up to +10%. At easterly wind exposed locations the climate change signal is more weak and higher and lower values are possible (-5% to +5%). Regarding the future changes of the wave directions, in general more wave events from W-NW and fewer events from N-NE can be expected. Analyses of extreme wave heights with a return period of 200 years show both increasing and decreasing values (-0.5m to +0.5m). The climate change signal of the extreme wave events is, as the same for the changes of the average wave conditions, more robust at locations which are exposed to westerly winds.

Research paper thumbnail of Climate Change and Coastal Protection: Adaptation Strategies for the German Baltic Sea Coast

Coastal Research Library, 2011

Consequences resulting from future climate change may be one of the most severe threats for peopl... more Consequences resulting from future climate change may be one of the most severe threats for people and economies in many countries of the world. With respect to coastal Protection, the resulting changed hydrodynamic impacts are discussed globally. At present, IPCC (2007) is estimating a world-wide average sea level rise of less than 1 m within the twenty-first century. Other sources

Research paper thumbnail of Collecting Statistical Methods for the Analysis of Climate Data as Service for Adaptation Projects

American Journal of Climate Change, 2015

The development of adaptation measures to climate change relies on data from climate models or im... more The development of adaptation measures to climate change relies on data from climate models or impact models. In order to analyze these large data sets or an ensemble of these data sets, the use of statistical methods is required. In this paper, the methodological approach to collecting, structuring and publishing the methods, which have been used or developed by former or present adaptation initiatives, is described. The intention is to communicate achieved knowledge and thus support future users. A key component is the participation of users in the development process. Main elements of the approach are standardized, template-based descriptions of the methods including the specific applications, references, and method assessment. All contributions have been quality checked, sorted, and placed in a larger context. The result is a report on statistical methods which is freely available as printed or online version. Examples of how to use the methods are presented in this paper and are also included in the brochure.

Research paper thumbnail of Future Extreme Waves at the German Baltic Sea Coast Derived from Regional Climate Model Runs

Coastal Engineering Proceedings, 2012

Information about possible changes of extreme wave heights are essential for the future safe desi... more Information about possible changes of extreme wave heights are essential for the future safe design of coastal and flood protection structures likes dykes, flood protection dunes, revetments etc. In this study, scenarios of regional climate change up to 2100 are used for the evaluation of changes of wave conditions. Analyses on calculated significant wave heights derived from extreme value statistics are showing a different signal of change for the selected locations along the German Baltic Sea Coast. The results are showing that extreme wave heights with a return level of 200 years can increase up to +14%. But also a decrease of down to -14% were found compared to actual conditions, depending on the location and climate change scenario applied. At the location of Warnemünde a slight increasing trend for the change of extreme wave heights could be found for 3 of 4 scenario runs with a maximum increase of +7%.

Research paper thumbnail of Future Changes in Wave Conditions at the German Baltic Sea Coast Based on a Hybrid Approach Using an Ensemble of Regional Climate Change Projections

Water

In this study, the projected future long-term changes of the local wave conditions at the German ... more In this study, the projected future long-term changes of the local wave conditions at the German Baltic Sea coast over the course of the 21st century are analyzed and assessed with special focus on model agreement, statistical significance and ranges/spread of the results. An ensemble of new regional climate model (RCM) simulations with the RCM REMO for three RCP forcing scenarios was used as input data. The outstanding feature of the simulations is that the data are available with a high horizontal resolution and at hourly timesteps which is a high temporal resolution and beneficial for the wind–wave modelling. A new data interface between RCM output data and wind–wave modelling has been developed. Suitable spatial aggregation methods of the RCM wind data have been tested and used to generate input for the calculation of waves at quasi deep-water conditions and at a mean water level with a hybrid approach that enables the fast compilation of future long-term time series of signific...

Research paper thumbnail of Modeling eelgrass spatial response to nutrient abatement measures in a changing climate

Ambio

For many coastal areas including the Baltic Sea, ambitious nutrient abatement goals have been set... more For many coastal areas including the Baltic Sea, ambitious nutrient abatement goals have been set to curb eutrophication, but benefits of such measures were normally not studied in light of anticipated climate change. To project the likely responses of nutrient abatement on eelgrass (Zostera marina), we coupled a species distribution model with a biogeochemical model, obtaining future water turbidity, and a wave model for predicting the future hydrodynamics in the coastal area. Using this, eelgrass distribution was modeled for different combinations of nutrient scenarios and future wind fields. We are the first to demonstrate that while under a business as usual scenario overall eelgrass area will not recover, nutrient reductions that fulfill the Helsinki Commission’s Baltic Sea Action Plan (BSAP) are likely to lead to a substantial areal expansion of eelgrass coverage, primarily at the current distribution’s lower depth limits, thereby overcompensating losses in shallow areas cause...

Research paper thumbnail of Long-term Changes of Waves at the German Baltic Sea Coast: Are There Trends from the Past?

Journal of Coastal Research

Research paper thumbnail of Operational wave forecast in the German Bight as part of a sensor- and risk based early warning system

Journal of Coastal Research

BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

Research paper thumbnail of On the Long-term Changes of Extreme Wave Heights at the German Baltic Sea Coast

Journal of Coastal Research

BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access t... more BioOne Complete (complete.BioOne.org) is a full-text database of 200 subscribed and open-access titles in the biological, ecological, and environmental sciences published by nonprofit societies, associations, museums, institutions, and presses.

Research paper thumbnail of Changes of 21 st Century's average and extreme wave conditions at the German Baltic Sea Coast due to global climate change

Journal of Coastal Research, 2013

ABSTRACT On the basis of hourly simulated wind data from a regional circulation model (Cosmo-CLM)... more ABSTRACT On the basis of hourly simulated wind data from a regional circulation model (Cosmo-CLM) long-term time series (1960-2100) of wave parameters were compiled for two of the SRES scenarios A1B, B1 at three locations along the German Baltic Sea Coast. The time series of wave parameters were calculated with the help of statistical correlations between observed wind and wave data, which were derived for the three locations in the study area. Furthermore, we applied a wave model for the Western Baltic Sea to correct some of the calculated wave information. The key findings of this study are that: (i) significant changes of average wind conditions can directly be linked to significant changes of the average wave conditions, (ii) a spatial pattern for the changes of average wave conditions can be found, (iii) no general trend can be found for the changes of extreme wave conditions. Comparisons of wind conditions, as simulated by the regional circulation model, for the past and the future are showing two main changes: (a) increases of average wind velocities to the end of the 21st century up to +4% and (b) more wind events from westerly and less events from easterly directions. The changes of the average wind velocities are resulting in increases of the average significant wave heights at westerly wind exposed locations up to +7% and small decreases of the average significant wave heights at easterly wind exposed locations. The future changes of the wave directions, with more wave events from W-NW and fewer events from N-NE, can be connected to the future changes of wind directions. Analyses of extreme wave heights with a return period of 200 years are showing both increasing and decreasing changes of up/down to +/-14%. At one location of the study area (Warnemunde) a slight increasing trend for the change of extreme wave heights to the end of the 21st century exists.

Research paper thumbnail of Statistical methods for the analysis of simulated and observed climate data, applied in projects and institutions dealing with climate change impact and adaptation., 135 S

Research paper thumbnail of Statistische Verfahren zur Auswertung von Klimadaten aus Modell und Beobachtung, eingesetzt in Projekten und Institutionen, die sich mit Klimafolgen und Anpassung befassen

Häufigkeit von Frosttagen nach Vegetationsbeginn/ zeitlicher Abstand von Terminen des letzten Fro... more Häufigkeit von Frosttagen nach Vegetationsbeginn/ zeitlicher Abstand von Terminen des letzten Frosttages und des Vegetationsbeginns .

Research paper thumbnail of Assessment of Future Wave Climate on basis of Wind-Wave- Correlations and Climate Change Scenarios

Consequences resulting from future climate change may be one of the most severe threats for peopl... more Consequences resulting from future climate change may be one of the most severe threats for people and economies in many countries of the world. With respect to coastal protection, the resulting changed hydrodynamic impacts are discussed globally. At present, IPCC (2007) is estimating a world-wide average sea level rise of less than 1.0m within the 21st century. Other sources (e.g. Rahmstorf & Schellnhuber, 2007) which are taking into account possible melting of the two main continental ice covers (Greenland and Antarctica), estimate significantly higher values especially over long periods. Besides the problem of sea level rise, also possible general changes of the local wave conditions are described. The model results indicate a small increase of the overall wave energy input for the future and a more significant change in the wave directions where westerly wave conditions may increase by 3.5% compared to the actual conditions.

Research paper thumbnail of The Use of a Regional Climate- and Wave Model for the Assessment of Changes of the Future Wave Climate in the Western Baltic Sea

Coastal Engineering Proceedings, 2014

On the basis of hourly simulated wind data from a regional circulation model (Cosmo-CLM) wave con... more On the basis of hourly simulated wind data from a regional circulation model (Cosmo-CLM) wave conditions from 1960 to 2100 are calculated for two realisations each of the global emission scenarios A1B and B1 using a numerical wave model for the area of the Western Baltic Sea. Comparisons of the 30 years averages of the wave conditions between the future and the past show that the changes of the average wave conditions can be directly linked to the changes of the average wind conditions. The changes of the average wave conditions and extreme wave events are characterised by high spatial and annual variability. In addition the changes depend on the time period of the comparison, the global emission scenario and the realisation of the climate model run. The bandwidth of the changes is moreover affected by the approach for the calculation of the wave conditions. A significant climate change signal of the average wave conditions is found at westerly wind exposed locations with predominant higher values of the average significant wave heights up to +10%. At easterly wind exposed locations the climate change signal is more weak and higher and lower values are possible (-5% to +5%). Regarding the future changes of the wave directions, in general more wave events from W-NW and fewer events from N-NE can be expected. Analyses of extreme wave heights with a return period of 200 years show both increasing and decreasing values (-0.5m to +0.5m). The climate change signal of the extreme wave events is, as the same for the changes of the average wave conditions, more robust at locations which are exposed to westerly winds.

Research paper thumbnail of Climate Change and Coastal Protection: Adaptation Strategies for the German Baltic Sea Coast

Coastal Research Library, 2011

Consequences resulting from future climate change may be one of the most severe threats for peopl... more Consequences resulting from future climate change may be one of the most severe threats for people and economies in many countries of the world. With respect to coastal Protection, the resulting changed hydrodynamic impacts are discussed globally. At present, IPCC (2007) is estimating a world-wide average sea level rise of less than 1 m within the twenty-first century. Other sources

Research paper thumbnail of Collecting Statistical Methods for the Analysis of Climate Data as Service for Adaptation Projects

American Journal of Climate Change, 2015

The development of adaptation measures to climate change relies on data from climate models or im... more The development of adaptation measures to climate change relies on data from climate models or impact models. In order to analyze these large data sets or an ensemble of these data sets, the use of statistical methods is required. In this paper, the methodological approach to collecting, structuring and publishing the methods, which have been used or developed by former or present adaptation initiatives, is described. The intention is to communicate achieved knowledge and thus support future users. A key component is the participation of users in the development process. Main elements of the approach are standardized, template-based descriptions of the methods including the specific applications, references, and method assessment. All contributions have been quality checked, sorted, and placed in a larger context. The result is a report on statistical methods which is freely available as printed or online version. Examples of how to use the methods are presented in this paper and are also included in the brochure.

Research paper thumbnail of Future Extreme Waves at the German Baltic Sea Coast Derived from Regional Climate Model Runs

Coastal Engineering Proceedings, 2012

Information about possible changes of extreme wave heights are essential for the future safe desi... more Information about possible changes of extreme wave heights are essential for the future safe design of coastal and flood protection structures likes dykes, flood protection dunes, revetments etc. In this study, scenarios of regional climate change up to 2100 are used for the evaluation of changes of wave conditions. Analyses on calculated significant wave heights derived from extreme value statistics are showing a different signal of change for the selected locations along the German Baltic Sea Coast. The results are showing that extreme wave heights with a return level of 200 years can increase up to +14%. But also a decrease of down to -14% were found compared to actual conditions, depending on the location and climate change scenario applied. At the location of Warnemünde a slight increasing trend for the change of extreme wave heights could be found for 3 of 4 scenario runs with a maximum increase of +7%.