Project acronym AGENSI
Project A Genetic View into Past Sea Ice Variability in the Arctic
Researcher (PI) Stijn DE SCHEPPER
Host Institution (HI) NORCE NORWEGIAN RESEARCH CENTRE AS
Call Details Consolidator Grant (CoG), PE10, ERC-2018-COG
Summary Arctic sea ice decline is the exponent of the rapidly transforming Arctic climate. The ensuing local and global implications can be understood by studying past climate transitions, yet few methods are available to examine past Arctic sea ice cover, severely restricting our understanding of sea ice in the climate system. The decline in Arctic sea ice cover is a ‘canary in the coalmine’ for the state of our climate, and if greenhouse gas emissions remain unchecked, summer sea ice loss may pass a critical threshold that could drastically transform the Arctic. Because historical observations are limited, it is crucial to have reliable proxies for assessing natural sea ice variability, its stability and sensitivity to climate forcing on different time scales. Current proxies address aspects of sea ice variability, but are limited due to a selective fossil record, preservation effects, regional applicability, or being semi-quantitative. With such restraints on our knowledge about natural variations and drivers, major uncertainties about the future remain.
I propose to develop and apply a novel sea ice proxy that exploits genetic information stored in marine sediments, sedimentary ancient DNA (sedaDNA). This innovation uses the genetic signature of phytoplankton communities from surface waters and sea ice as it gets stored in sediments. This wealth of information has not been explored before for reconstructing sea ice conditions. Preliminary results from my cross-disciplinary team indicate that our unconventional approach can provide a detailed, qualitative account of past sea ice ecosystems and quantitative estimates of sea ice parameters. I will address fundamental questions about past Arctic sea ice variability on different timescales, information essential to provide a framework upon which to assess the ecological and socio-economic consequences of a changing Arctic. This new proxy is not limited to sea ice research and can transform the field of paleoceanography.
Summary
Arctic sea ice decline is the exponent of the rapidly transforming Arctic climate. The ensuing local and global implications can be understood by studying past climate transitions, yet few methods are available to examine past Arctic sea ice cover, severely restricting our understanding of sea ice in the climate system. The decline in Arctic sea ice cover is a ‘canary in the coalmine’ for the state of our climate, and if greenhouse gas emissions remain unchecked, summer sea ice loss may pass a critical threshold that could drastically transform the Arctic. Because historical observations are limited, it is crucial to have reliable proxies for assessing natural sea ice variability, its stability and sensitivity to climate forcing on different time scales. Current proxies address aspects of sea ice variability, but are limited due to a selective fossil record, preservation effects, regional applicability, or being semi-quantitative. With such restraints on our knowledge about natural variations and drivers, major uncertainties about the future remain.
I propose to develop and apply a novel sea ice proxy that exploits genetic information stored in marine sediments, sedimentary ancient DNA (sedaDNA). This innovation uses the genetic signature of phytoplankton communities from surface waters and sea ice as it gets stored in sediments. This wealth of information has not been explored before for reconstructing sea ice conditions. Preliminary results from my cross-disciplinary team indicate that our unconventional approach can provide a detailed, qualitative account of past sea ice ecosystems and quantitative estimates of sea ice parameters. I will address fundamental questions about past Arctic sea ice variability on different timescales, information essential to provide a framework upon which to assess the ecological and socio-economic consequences of a changing Arctic. This new proxy is not limited to sea ice research and can transform the field of paleoceanography.
Max ERC Funding
2 615 858 €
Duration
Start date: 2019-08-01, End date: 2024-07-31
Project acronym BPT
Project BEYOND PLATE TECTONICS
Researcher (PI) Trond Helge Torsvik
Host Institution (HI) UNIVERSITETET I OSLO
Call Details Advanced Grant (AdG), PE10, ERC-2010-AdG_20100224
Summary Plate tectonics characterises the complex and dynamic evolution of the outer shell of the Earth in terms of rigid plates. These tectonic plates overlie and interact with the Earth's mantle, which is slowly convecting owing to energy released by the decay of radioactive nuclides in the Earth's interior. Even though links between mantle convection and plate tectonics are becoming more evident, notably through subsurface tomographic images, advances in mineral physics and improved absolute plate motion reference frames, there is still no generally accepted mechanism that consistently explains plate tectonics and mantle convection in one framework. We will integrate plate tectonics into mantle dynamics and develop a theory that explains plate motions quantitatively and dynamically. This requires consistent and detailed reconstructions of plate motions through time (Objective 1).
A new model of plate kinematics will be linked to the mantle with the aid of a new global reference frame based on moving hotspots and on palaeomagnetic data. The global reference frame will be corrected for true polar wander in order to develop a global plate motion reference frame with respect to the mantle back to Pangea (ca. 320 million years) and possibly Gondwana assembly (ca. 550 million years). The resulting plate reconstructions will constitute the input to subduction models that are meant to test the consistency between the reference frame and subduction histories. The final outcome will be a novel global subduction reference frame, to be used to unravel links between the surface and deep Earth (Objective 2).
Summary
Plate tectonics characterises the complex and dynamic evolution of the outer shell of the Earth in terms of rigid plates. These tectonic plates overlie and interact with the Earth's mantle, which is slowly convecting owing to energy released by the decay of radioactive nuclides in the Earth's interior. Even though links between mantle convection and plate tectonics are becoming more evident, notably through subsurface tomographic images, advances in mineral physics and improved absolute plate motion reference frames, there is still no generally accepted mechanism that consistently explains plate tectonics and mantle convection in one framework. We will integrate plate tectonics into mantle dynamics and develop a theory that explains plate motions quantitatively and dynamically. This requires consistent and detailed reconstructions of plate motions through time (Objective 1).
A new model of plate kinematics will be linked to the mantle with the aid of a new global reference frame based on moving hotspots and on palaeomagnetic data. The global reference frame will be corrected for true polar wander in order to develop a global plate motion reference frame with respect to the mantle back to Pangea (ca. 320 million years) and possibly Gondwana assembly (ca. 550 million years). The resulting plate reconstructions will constitute the input to subduction models that are meant to test the consistency between the reference frame and subduction histories. The final outcome will be a novel global subduction reference frame, to be used to unravel links between the surface and deep Earth (Objective 2).
Max ERC Funding
2 499 010 €
Duration
Start date: 2011-05-01, End date: 2016-04-30
Project acronym C4T
Project Climate change across Cenozoic cooling steps reconstructed with clumped isotope thermometry
Researcher (PI) Anna Nele Meckler
Host Institution (HI) UNIVERSITETET I BERGEN
Call Details Starting Grant (StG), PE10, ERC-2014-STG
Summary The Earth's climate system contains a highly complex interplay of numerous components, such as atmospheric greenhouse gases, ice sheets, and ocean circulation. Due to nonlinearities and feedbacks, changes to the system can result in rapid transitions to radically different climate states. In light of rising greenhouse gas levels there is an urgent need to better understand climate at such tipping points. Reconstructions of profound climate changes in the past provide crucial insight into our climate system and help to predict future changes. However, all proxies we use to reconstruct past climate depend on assumptions that are in addition increasingly uncertain back in time. A new kind of temperature proxy, the carbonate ‘clumped isotope’ thermometer, has great potential to overcome these obstacles. The proxy relies on thermodynamic principles, taking advantage of the temperature-dependence of the binding strength between different isotopes of carbon and oxygen, which makes it independent of other variables. Yet, widespread application of this technique in paleoceanography is currently prevented by the required large sample amounts, which are difficult to obtain from ocean sediments. If applied to the minute carbonate shells preserved in the sediments, this proxy would allow robust reconstructions of past temperatures in the surface and deep ocean, as well as global ice volume, far back in time. Here I propose to considerably decrease sample amount requirements of clumped isotope thermometry, building on recent successful modifications of the method and ideas for further analytical improvements. This will enable my group and me to thoroughly ground-truth the proxy for application in paleoceanography and for the first time apply it to aspects of past climate change across major climate transitions in the past, where clumped isotope thermometry can immediately contribute to solving long-standing first-order questions and allow for major progress in the field.
Summary
The Earth's climate system contains a highly complex interplay of numerous components, such as atmospheric greenhouse gases, ice sheets, and ocean circulation. Due to nonlinearities and feedbacks, changes to the system can result in rapid transitions to radically different climate states. In light of rising greenhouse gas levels there is an urgent need to better understand climate at such tipping points. Reconstructions of profound climate changes in the past provide crucial insight into our climate system and help to predict future changes. However, all proxies we use to reconstruct past climate depend on assumptions that are in addition increasingly uncertain back in time. A new kind of temperature proxy, the carbonate ‘clumped isotope’ thermometer, has great potential to overcome these obstacles. The proxy relies on thermodynamic principles, taking advantage of the temperature-dependence of the binding strength between different isotopes of carbon and oxygen, which makes it independent of other variables. Yet, widespread application of this technique in paleoceanography is currently prevented by the required large sample amounts, which are difficult to obtain from ocean sediments. If applied to the minute carbonate shells preserved in the sediments, this proxy would allow robust reconstructions of past temperatures in the surface and deep ocean, as well as global ice volume, far back in time. Here I propose to considerably decrease sample amount requirements of clumped isotope thermometry, building on recent successful modifications of the method and ideas for further analytical improvements. This will enable my group and me to thoroughly ground-truth the proxy for application in paleoceanography and for the first time apply it to aspects of past climate change across major climate transitions in the past, where clumped isotope thermometry can immediately contribute to solving long-standing first-order questions and allow for major progress in the field.
Max ERC Funding
1 877 209 €
Duration
Start date: 2015-08-01, End date: 2020-07-31
Project acronym COMTESSA
Project Camera Observation and Modelling of 4D Tracer Dispersion in the Atmosphere
Researcher (PI) Andreas Stohl
Host Institution (HI) NORSK INSTITUTT FOR LUFTFORSKNING STIFTELSE
Call Details Advanced Grant (AdG), PE10, ERC-2014-ADG
Summary COMTESSA will push back the limits of our understanding of turbulence and plume dispersion in the atmosphere by bringing together full four-dimensional (space and time) observations of a (nearly) passive tracer (sulfur dioxide, SO2), with advanced data analysis and turbulence and dispersion modelling.
Observations will be made with six cameras sensitive to ultraviolet (UV) radiation and three cameras sensitive to infrared (IR) radiation. The UV cameras will be built specifically for this project where high sensitivity and fast sampling is important. The accuracy of UV and IR retrievals will be improved by using a state-of-the art-3D radiative transfer model.
Controlled puff and plume releases of SO2 will be made from a tower, which will be observed by all cameras, yielding multiple 2D images of SO2 integrated along the line of sight. The simultaneous observations will allow - for the first time - a tomographic reconstruction of the 3D tracer concentration distribution at high space (< 1 m) and time (>10 Hz) resolution. An optical flow code will be used to determine the eddy-resolved velocity vector field of the plume. Special turbulent phenomena (e.g. plume rise) will be studied using existing SO2 sources (e.g. smelters, power plants, volcanic fumaroles).
Analysis of the novel campaign observations will deepen our understanding of turbulence and tracer dispersion in the atmosphere. For instance, for the first time we will be able to extensively measure the concentration probability density function (PDF) in a plume not only near the ground but also at high-er altitudes; quantify relative and absolute dispersion; estimate the value of the Richardson-Obukhov constant, etc. We will also use the data to evaluate state-of-the-art LES and Lagrangian dispersion models and revise their underlying parameterizations.
COMTESSA’s vision is that the project results will lead to large improvements of tracer transport in all atmospheric models.
Summary
COMTESSA will push back the limits of our understanding of turbulence and plume dispersion in the atmosphere by bringing together full four-dimensional (space and time) observations of a (nearly) passive tracer (sulfur dioxide, SO2), with advanced data analysis and turbulence and dispersion modelling.
Observations will be made with six cameras sensitive to ultraviolet (UV) radiation and three cameras sensitive to infrared (IR) radiation. The UV cameras will be built specifically for this project where high sensitivity and fast sampling is important. The accuracy of UV and IR retrievals will be improved by using a state-of-the art-3D radiative transfer model.
Controlled puff and plume releases of SO2 will be made from a tower, which will be observed by all cameras, yielding multiple 2D images of SO2 integrated along the line of sight. The simultaneous observations will allow - for the first time - a tomographic reconstruction of the 3D tracer concentration distribution at high space (< 1 m) and time (>10 Hz) resolution. An optical flow code will be used to determine the eddy-resolved velocity vector field of the plume. Special turbulent phenomena (e.g. plume rise) will be studied using existing SO2 sources (e.g. smelters, power plants, volcanic fumaroles).
Analysis of the novel campaign observations will deepen our understanding of turbulence and tracer dispersion in the atmosphere. For instance, for the first time we will be able to extensively measure the concentration probability density function (PDF) in a plume not only near the ground but also at high-er altitudes; quantify relative and absolute dispersion; estimate the value of the Richardson-Obukhov constant, etc. We will also use the data to evaluate state-of-the-art LES and Lagrangian dispersion models and revise their underlying parameterizations.
COMTESSA’s vision is that the project results will lead to large improvements of tracer transport in all atmospheric models.
Max ERC Funding
2 800 000 €
Duration
Start date: 2015-11-01, End date: 2020-10-31
Project acronym DIME
Project Disequilibirum metamorphism of stressed lithosphere
Researcher (PI) Bjørn Jamtveit
Host Institution (HI) UNIVERSITETET I OSLO
Call Details Advanced Grant (AdG), PE10, ERC-2014-ADG
Summary Most changes in mineralogy, density, and rheology of the Earth’s lithosphere take place by metamorphism, whereby rocks evolve through interactions between minerals and fluids. These changes are coupled with a large range of geodynamic processes and they have first order effects on the global geochemical cycles of a large number of elements.
In the presence of fluids, metamorphic reactions are fast compared to tectonically induced changes in pressure and temperature. Hence, during fluid-producing metamorphism, rocks evolve through near-equilibrium states. However, much of the Earth’s lower and middle crust, and a significant fraction of the upper mantle do not contain free fluids. These parts of the lithosphere exist in a metastable state and are mechanically strong. When subject to changing temperature and pressure conditions at plate boundaries or elsewhere, these rocks do not react until exposed to externally derived fluids.
Metamorphism of such rocks consumes fluids, and takes place far from equilibrium through a complex coupling between fluid migration, chemical reactions, and deformation processes. This disequilibrium metamorphism is characterized by fast reaction rates, release of large amounts of energy in the form of heat and work, and a strong coupling to far-field tectonic stress.
Our overarching goal is to provide the first quantitative physics-based model of disequilibrium metamorphism that properly connects fluid-rock interactions at the micro and nano-meter scale to lithosphere scale stresses. This model will include quantification of the forces required to squeeze fluids out of grain-grain contacts for geologically relevant materials (Objective 1), a new experimentally based model describing how the progress of volatilization reactions depends on tectonic stress (Objective 2), and testing of this model by analyzing the kinetics of a natural serpentinization process through the Oman Ophiolite Drilling Project (Objective 3).
Summary
Most changes in mineralogy, density, and rheology of the Earth’s lithosphere take place by metamorphism, whereby rocks evolve through interactions between minerals and fluids. These changes are coupled with a large range of geodynamic processes and they have first order effects on the global geochemical cycles of a large number of elements.
In the presence of fluids, metamorphic reactions are fast compared to tectonically induced changes in pressure and temperature. Hence, during fluid-producing metamorphism, rocks evolve through near-equilibrium states. However, much of the Earth’s lower and middle crust, and a significant fraction of the upper mantle do not contain free fluids. These parts of the lithosphere exist in a metastable state and are mechanically strong. When subject to changing temperature and pressure conditions at plate boundaries or elsewhere, these rocks do not react until exposed to externally derived fluids.
Metamorphism of such rocks consumes fluids, and takes place far from equilibrium through a complex coupling between fluid migration, chemical reactions, and deformation processes. This disequilibrium metamorphism is characterized by fast reaction rates, release of large amounts of energy in the form of heat and work, and a strong coupling to far-field tectonic stress.
Our overarching goal is to provide the first quantitative physics-based model of disequilibrium metamorphism that properly connects fluid-rock interactions at the micro and nano-meter scale to lithosphere scale stresses. This model will include quantification of the forces required to squeeze fluids out of grain-grain contacts for geologically relevant materials (Objective 1), a new experimentally based model describing how the progress of volatilization reactions depends on tectonic stress (Objective 2), and testing of this model by analyzing the kinetics of a natural serpentinization process through the Oman Ophiolite Drilling Project (Objective 3).
Max ERC Funding
2 900 000 €
Duration
Start date: 2015-09-01, End date: 2021-08-31
Project acronym EPIFISH
Project INNOVATIVE EPIGENETIC MARKERS FOR FISH DOMESTICATION
Researcher (PI) Jorge Manuel De Oliveira Fernandes
Host Institution (HI) NORD UNIVERSITET
Call Details Consolidator Grant (CoG), LS9, ERC-2015-CoG
Summary Aquaculture is the fastest growing food production sector in the world, since there is an increasing demand for fish protein to feed a growing global population, which cannot be met by fisheries. In order to ensure the sustainability of this sector it is critical to domesticate and selectively improve the major commercial fish species. To date, the genetic markers used in selective breeding of fish account only for a fraction of the observed phenotypic variation. EPIFISH is a scientifically innovative and timely project that will address fish domestication and selection from a new perspective using a multidisciplinary approach. The rapid pace of substantial phenotypic changes during adaptation to new environmental conditions in fish undergoing domestication raises the original hypothesis that epigenetic mechanisms are involved in this process. Thus, the overarching aim of EPIFISH is to ascertain the importance of epigenetics in fish domestication using the Nile tilapia (Oreochromis niloticus) as model species. Specific objectives are i) to determine how selection affects the miRNA transcriptome and the epigenetic landscape during domestication, ii) to perform a functional characterization of miRNA variants and epigenetic alleles associated with growth, and iii) to validate them as potential epigenetic markers for future selective breeding programmes. The identification of epigenetic markers will be a ground-breaking element of EPIFISH with major impact on aquaculture biotechnology, since they will enable the development and application of epigenomic selection as a new feature in future selective breeding programmes. Moreover, the project outcomes will provide novel mechanistic insights into the role of epigenetics in fish domestication, which will surely open new horizons for future frontier research in epigenetics, namely transgenerational inheritance and nutritional epigenetics.
Summary
Aquaculture is the fastest growing food production sector in the world, since there is an increasing demand for fish protein to feed a growing global population, which cannot be met by fisheries. In order to ensure the sustainability of this sector it is critical to domesticate and selectively improve the major commercial fish species. To date, the genetic markers used in selective breeding of fish account only for a fraction of the observed phenotypic variation. EPIFISH is a scientifically innovative and timely project that will address fish domestication and selection from a new perspective using a multidisciplinary approach. The rapid pace of substantial phenotypic changes during adaptation to new environmental conditions in fish undergoing domestication raises the original hypothesis that epigenetic mechanisms are involved in this process. Thus, the overarching aim of EPIFISH is to ascertain the importance of epigenetics in fish domestication using the Nile tilapia (Oreochromis niloticus) as model species. Specific objectives are i) to determine how selection affects the miRNA transcriptome and the epigenetic landscape during domestication, ii) to perform a functional characterization of miRNA variants and epigenetic alleles associated with growth, and iii) to validate them as potential epigenetic markers for future selective breeding programmes. The identification of epigenetic markers will be a ground-breaking element of EPIFISH with major impact on aquaculture biotechnology, since they will enable the development and application of epigenomic selection as a new feature in future selective breeding programmes. Moreover, the project outcomes will provide novel mechanistic insights into the role of epigenetics in fish domestication, which will surely open new horizons for future frontier research in epigenetics, namely transgenerational inheritance and nutritional epigenetics.
Max ERC Funding
1 996 189 €
Duration
Start date: 2016-07-01, End date: 2021-06-30
Project acronym FEEC-A
Project Finite Element Exterior Calculus and Applications
Researcher (PI) Ragnar Winther
Host Institution (HI) UNIVERSITETET I OSLO
Call Details Advanced Grant (AdG), PE1, ERC-2013-ADG
Summary "The finite element method is one of the most successful techniques for designing numerical methods for systems of partial differential equations (PDEs). It is not only a methodology for developing numerical algorithms, but also a mathematical framework in which to explore their behavior. The finite element exterior calculus (FEEC) provides a new structure that produces a deeper understanding of the finite element method and its connections to the partial differential equation being approximated. The goal is to develop discretizations which are compatible with the geometric, topological, and algebraic structures which underlie well-posedness of the partial differential equation. The phrase FEEC was first used in a paper the PI wrote for Acta Numerica in 2006, together with his coworkers, D.N. Arnold and R.S. Falk. The general philosophy of FEEC has led to the design of new algorithms and software developments, also in areas beyond the direct application of the theory. The present project will be devoted to further development of the foundations of FEEC, and to direct or indirect use of FEEC in specific applications. The ambition is to set the scene for a nubmer of new research directions based on FEEC by giving ground-braking contributions to its foundation. The aim is also to use FEEC as a tool, or a guideline, to extend the foundation of numerical PDEs to a variety of problems for which this foundation does not exist. The more application oriented parts of the project includes topics like numerical methods for elasticity, its generalizations to more general models in materials science such as viscoelasticity, poroelasticity, and liquid crystals, and the applications of these models to CO2 storage and deformations of the spinal cord."
Summary
"The finite element method is one of the most successful techniques for designing numerical methods for systems of partial differential equations (PDEs). It is not only a methodology for developing numerical algorithms, but also a mathematical framework in which to explore their behavior. The finite element exterior calculus (FEEC) provides a new structure that produces a deeper understanding of the finite element method and its connections to the partial differential equation being approximated. The goal is to develop discretizations which are compatible with the geometric, topological, and algebraic structures which underlie well-posedness of the partial differential equation. The phrase FEEC was first used in a paper the PI wrote for Acta Numerica in 2006, together with his coworkers, D.N. Arnold and R.S. Falk. The general philosophy of FEEC has led to the design of new algorithms and software developments, also in areas beyond the direct application of the theory. The present project will be devoted to further development of the foundations of FEEC, and to direct or indirect use of FEEC in specific applications. The ambition is to set the scene for a nubmer of new research directions based on FEEC by giving ground-braking contributions to its foundation. The aim is also to use FEEC as a tool, or a guideline, to extend the foundation of numerical PDEs to a variety of problems for which this foundation does not exist. The more application oriented parts of the project includes topics like numerical methods for elasticity, its generalizations to more general models in materials science such as viscoelasticity, poroelasticity, and liquid crystals, and the applications of these models to CO2 storage and deformations of the spinal cord."
Max ERC Funding
2 059 687 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
Project acronym FUNDMS
Project Functionalisation of Diluted Magnetic Semiconductors
Researcher (PI) Tomasz Dietl
Host Institution (HI) INSTYTUT FIZYKI POLSKIEJ AKADEMII NAUK
Call Details Advanced Grant (AdG), PE3, ERC-2008-AdG
Summary Low-temperature studies of transition metal doped III-V and II-VI compounds carried out over the last decade have demonstrated the unprecedented opportunity offered by these systems for exploring physical phenomena and device concepts in previously unavailable combinations of quantum structures and ferromagnetism in semiconductors. The work proposed here aims at combining and at advancing epitaxial methods, spatially-resolved nano-characterisation tools, and theoretical modelling in order to understand the intricate interplay between carrier localisation, magnetism, and magnetic ion distribution in DMS, and to develop functional DMS structures. To accomplish these goals we will take advantage of two recent breakthroughs in materials engineering. First, the attainment of high-k oxides makes now possible to generate interfacial hole densities up to 10^21 cm-3. We will exploit gated thin layers of DMS phosphides, nitrides, and oxides, in which hole delocalization and thus high temperature ferromagnetism is to be expected under gate bias. Furthermore we will systematically investigate how the Curie temperature of (Ga,Mn)As can be risen above 180 K. Second, the progress in nanoscale chemical analysis has allowed demonstrating that high temperature ferromagnetism of semiconductors results from nanoscale crystallographic or chemical phase separations into regions containing a large concentration of the magnetic constituent. We will elaborate experimentally and theoretically epitaxy and co-doping protocols for controlling the self-organised growth of magnetic nanostructures, utilizing broadly synchrotron radiation and nanoscopic characterisation tools. The established methods will allow us to obtain on demand either magnetic nano-dots or magnetic nano-columns embedded in a semiconductor host, for which we predict, and will demonstrate, ground-breaking functionalities. We will also assess reports on the possibility of high-temperature ferromagnetism without magnetic ions.
Summary
Low-temperature studies of transition metal doped III-V and II-VI compounds carried out over the last decade have demonstrated the unprecedented opportunity offered by these systems for exploring physical phenomena and device concepts in previously unavailable combinations of quantum structures and ferromagnetism in semiconductors. The work proposed here aims at combining and at advancing epitaxial methods, spatially-resolved nano-characterisation tools, and theoretical modelling in order to understand the intricate interplay between carrier localisation, magnetism, and magnetic ion distribution in DMS, and to develop functional DMS structures. To accomplish these goals we will take advantage of two recent breakthroughs in materials engineering. First, the attainment of high-k oxides makes now possible to generate interfacial hole densities up to 10^21 cm-3. We will exploit gated thin layers of DMS phosphides, nitrides, and oxides, in which hole delocalization and thus high temperature ferromagnetism is to be expected under gate bias. Furthermore we will systematically investigate how the Curie temperature of (Ga,Mn)As can be risen above 180 K. Second, the progress in nanoscale chemical analysis has allowed demonstrating that high temperature ferromagnetism of semiconductors results from nanoscale crystallographic or chemical phase separations into regions containing a large concentration of the magnetic constituent. We will elaborate experimentally and theoretically epitaxy and co-doping protocols for controlling the self-organised growth of magnetic nanostructures, utilizing broadly synchrotron radiation and nanoscopic characterisation tools. The established methods will allow us to obtain on demand either magnetic nano-dots or magnetic nano-columns embedded in a semiconductor host, for which we predict, and will demonstrate, ground-breaking functionalities. We will also assess reports on the possibility of high-temperature ferromagnetism without magnetic ions.
Max ERC Funding
2 440 000 €
Duration
Start date: 2009-01-01, End date: 2013-12-31
Project acronym HOPE
Project Humans On Planet Earth - Long-term impacts on biosphere dynamics
Researcher (PI) Harry John Betteley BIRKS
Host Institution (HI) UNIVERSITETET I BERGEN
Call Details Advanced Grant (AdG), PE10, ERC-2016-ADG
Summary A critical question in Earth system science is what was the impact of prehistoric people on the biosphere and climate? There is much information about human impact through clearance, agriculture, erosion, and modifying water and nutrient budgets. Humans have greatly changed the Earth in the last 8000 years, but did humans modify the major ecological processes (e.g. assembly rules) that shape community assembly and dynamics? Did inter-relationships between processes change in response to human impact? Lyons et al. & Dietl (2016 Nature) suggest that human activities in the last 6000 years had such impacts. Dietl proposes that using past ‘natural experiments’ to predict future changes is “flawed” and “out is the use of uniformitarianism”. As using natural experiments is a common strategy and uniformitarianism is the major working concept in Earth sciences, it is imperative to test whether prehistoric human activity changed major ecological processes determining community development. To test this hypothesis, patterns in pollen-stratigraphical data for the past 11,500 years from over 2000 sites across the globe will be explored consistently using numerical techniques to discern changes in 25 ecosystem properties (richness, evenness, and diversity; turnover; rates of change; taxon co-occurrences, etc.). Patterns in these properties will be compared statistically at sites within biomes, between biomes, within continents, and between continents to test the hypotheses that prehistoric human activities changed the basic ecological processes of community assembly and that their inter-relationships changed through time. These areas provide major contrasts in human prehistory and biomes. HOPE is interdisciplinary: pollen analysis, databases, multivariate analysis, ecology, new statistical methods, numerical simulations, statistical modelling. HOPE’s impact goes beyond human effects on the biosphere and extends to the very core of Earth science’s basic conceptual framework.
Summary
A critical question in Earth system science is what was the impact of prehistoric people on the biosphere and climate? There is much information about human impact through clearance, agriculture, erosion, and modifying water and nutrient budgets. Humans have greatly changed the Earth in the last 8000 years, but did humans modify the major ecological processes (e.g. assembly rules) that shape community assembly and dynamics? Did inter-relationships between processes change in response to human impact? Lyons et al. & Dietl (2016 Nature) suggest that human activities in the last 6000 years had such impacts. Dietl proposes that using past ‘natural experiments’ to predict future changes is “flawed” and “out is the use of uniformitarianism”. As using natural experiments is a common strategy and uniformitarianism is the major working concept in Earth sciences, it is imperative to test whether prehistoric human activity changed major ecological processes determining community development. To test this hypothesis, patterns in pollen-stratigraphical data for the past 11,500 years from over 2000 sites across the globe will be explored consistently using numerical techniques to discern changes in 25 ecosystem properties (richness, evenness, and diversity; turnover; rates of change; taxon co-occurrences, etc.). Patterns in these properties will be compared statistically at sites within biomes, between biomes, within continents, and between continents to test the hypotheses that prehistoric human activities changed the basic ecological processes of community assembly and that their inter-relationships changed through time. These areas provide major contrasts in human prehistory and biomes. HOPE is interdisciplinary: pollen analysis, databases, multivariate analysis, ecology, new statistical methods, numerical simulations, statistical modelling. HOPE’s impact goes beyond human effects on the biosphere and extends to the very core of Earth science’s basic conceptual framework.
Max ERC Funding
2 278 884 €
Duration
Start date: 2018-01-01, End date: 2022-12-31
Project acronym HyLEF
Project Hydrodynamic Limits and Equilibrium Fluctuations: universality from stochastic systems
Researcher (PI) ANA PATRICIA CARVALHO GONÇALVES
Host Institution (HI) INSTITUTO SUPERIOR TECNICO
Call Details Starting Grant (StG), PE1, ERC-2016-STG
Summary A classical problem in the field of interacting particle systems (IPS) is to derive the macroscopic laws of the thermodynamical quantities of a physical system by considering an underlying microscopic dynamics which is composed of particles that move according to some prescribed stochastic, or deterministic, law. The macroscopic laws can be partial differential equations (PDE) or stochastic PDE (SPDE) depending on whether one is looking at the convergence to the mean or to the fluctuations around that mean. One of the purposes of this research project is to give a mathematically rigorous description of the derivation of SPDE from different IPS. We will focus on the derivation of the stochastic Burgers equation (SBE) and its integrated counterpart, namely, the KPZ equation, as well as their fractional versions. The KPZ equation is conjectured to be a universal SPDE describing the fluctuations of randomly growing interfaces of 1d stochastic dynamics close to a stationary state. With this study we want to characterize what is known as the KPZ universality class: the weak and strong conjectures. The latter states that there exists a universal process, namely the KPZ fixed point, which is a fixed point of the renormalization group operator of space-time scaling 1:2:3, for which the KPZ is also invariant. The former states that the fluctuations of a large class of 1d conservative microscopic dynamics are ruled by stationary solutions of the KPZ. Our goal is threefold: first, to derive the KPZ equation from general weakly asymmetric systems, showing its universality; second, to derive new SPDE, which are less studied in the literature, as the fractional KPZ from IPS which allow long jumps, the KPZ with boundary conditions from IPS in contact with reservoirs or with defects, and coupled KPZ from IPS with more than one conserved quantity. Finally, we will analyze the fluctuations of purely strong asymmetric systems, which are conjectured to be given by the KPZ fixed point.
Summary
A classical problem in the field of interacting particle systems (IPS) is to derive the macroscopic laws of the thermodynamical quantities of a physical system by considering an underlying microscopic dynamics which is composed of particles that move according to some prescribed stochastic, or deterministic, law. The macroscopic laws can be partial differential equations (PDE) or stochastic PDE (SPDE) depending on whether one is looking at the convergence to the mean or to the fluctuations around that mean. One of the purposes of this research project is to give a mathematically rigorous description of the derivation of SPDE from different IPS. We will focus on the derivation of the stochastic Burgers equation (SBE) and its integrated counterpart, namely, the KPZ equation, as well as their fractional versions. The KPZ equation is conjectured to be a universal SPDE describing the fluctuations of randomly growing interfaces of 1d stochastic dynamics close to a stationary state. With this study we want to characterize what is known as the KPZ universality class: the weak and strong conjectures. The latter states that there exists a universal process, namely the KPZ fixed point, which is a fixed point of the renormalization group operator of space-time scaling 1:2:3, for which the KPZ is also invariant. The former states that the fluctuations of a large class of 1d conservative microscopic dynamics are ruled by stationary solutions of the KPZ. Our goal is threefold: first, to derive the KPZ equation from general weakly asymmetric systems, showing its universality; second, to derive new SPDE, which are less studied in the literature, as the fractional KPZ from IPS which allow long jumps, the KPZ with boundary conditions from IPS in contact with reservoirs or with defects, and coupled KPZ from IPS with more than one conserved quantity. Finally, we will analyze the fluctuations of purely strong asymmetric systems, which are conjectured to be given by the KPZ fixed point.
Max ERC Funding
1 179 496 €
Duration
Start date: 2016-12-01, End date: 2021-11-30
