Fossil fuels - olil, gas
Fossil fuels are derived from organic material that has accumulated in sedimentary rocks (source rocks). Low temperature thermal alteration leads to break-down of this organic matter into coal and hydrocarbons. The latter migrate as oil and/or gas into porous rock formations, such as sandstones, which make up the reservoir rocks.
About 80% of the world’s energy resources today come from fossil fuels – oil, gas and coal. Of these, oil is the most important source of energy, primarily because of its importance for the transport sector. There are two main problems related to our use of fossils fuels: limitations on supply and possible damage to the environment. The most serious threat to the environment is a possible greenhouse effect due to an increase of CO2 in the atmosphere. Estimations of the availability of fossil fuel vary. Most prognoses suggest that, within a decade or two, availability of oil will diminish. Later on, there will be a shortage of natural gas. Vast coal reserves will remain, along with other resources such as oil shales, oil sands, peat, etc., but the use of these is less favourable both for economic and environmental reasons. Prospecting for oil and gas will continue to be very important for our society in the 21st century. These geo-resources will be more difficult to find and will demand close collaboration between geoscientists and engineers. This applies even if the greenhouse effect of CO2 production demands that society reduces the use of fossil fuels quicker than is required by their availability. The price of fossil fuels will increase in pace with the rate at which the resources are depleted and demand increases (e.g. pressure from China and India on the market today) and this will promote the development of alternative energy resources.
The Earth's internal heat is a sustainable and environmentally friendly energy resource
Todays technology only allows us access to geothermal energy stored near the surface of Earth. Small-scale geothermal heat pumps heat up a growing part of Swedish homes. Earth temperature increases with depth, on average about 30 degrees C per kilometre. Larger plants, that extract heat from a greater depth, are therefore very interesting. The biggest such plant in Sweden is found outside Lund in southern Sweden where much of the city's energy for central heating derives from a geothermal source at 700 m depth. Large-scale geothermal plants are today limited to specific geological environments, primarily volcanic such as in Iceland where about 700 MW of electricity are produced from steam from geothermal fields.
Geothermal energy is present everywhere under our feet. The questions are how deep we need to drill in order to mine it, how much water is available in the rocks to transport the heat, and how mobile the water is, e.g. how permeable the rocks are. Development of deep-drilling technology and more detailed knowledge about heat sources in the Earth's crust are also important for further exploitation of geothermal energy.
Geothermal research at Uppsala focusses on earth-scientific aspects. Current projects within the geophysics group at Uppsala University in collaboration with universities and other institutions in Iceland and the USA focus on detailed structure studies of the top 5 km of the crust in volcanic areas in Iceland and the USA where a number of geothermal power plants are in operation. Sub-surface structure is illuminated by microearthquakes and the waves they generate. We can map how wave speeds vary within the crust, how the waves are damped and how their properties vary with their propagation direction. That way we can learn about heat sources in the crust, about the distribution of porosity in the crust and the nature of associated permeability, and about the effects the mining of geothermal energy affects the power plant's reservoirs. A part of the research focusses on how to jointly interpret different geophysical measurements, such as seismic and electromagnetic. The latter are sensitive to the electrical conductivity of the sub surface which depends strongly on temperature, pressure and the degree of alteration. The geophysics group is also strongly involved in deep drilling projects in Sweden together with numerous swedish and international institutions. One of the projects' goeals is to better map out geothermal heat sources in Sweden. A program to measure temperatures in existing boreholes into swedish bedrock is in progress aiming to achieve this goal.
Glaciers are landforms of ice which are sensitive indicators of changes in climate
and environment. Ice fields and ice sheets are superb archieves for trends and
changes in climate and environmental history and serve as tools in our knowledge
of how future climates may behave.
Ice cores An important branch of today's glaciology is focused on retrieving records onclimate of the past by drilling ice cores out from ice sheets and ice fields. The ice cores are analyzed either simultaneously with the retrieval in the field, or sampled later for more laborious analytic work. The biology, chemistry and the physics of the ice core show how the climatic and environmental change and variability of the region from where the ice core is taken. In Uppsala we are focusing on ice cores from Greenland and Svalbard.
Mass balance Another important aspect of glaciers is their mass balance. Mass balance is the net sum of snow accumulation and ice loss through ablation. Since both accumulation and ablation is related to the climate, mass balance is a good indicator of the impact of climate change on glaciers. We hope that studying the present relationship between climate and mass balance will give information about future glacier responses to a global warming. Mass balance can be studied in many different ways. In the Nordic excellence center SVALI we also work on climate and weather models together with measured data to get a better control of the regional variations in mass balance, in order to make future projections of changes in ice sheets volume. We work primarily with the atmospheric model WRF, and integrate better melting models in earth science models (ESM).
Ice dynamics Another domain within glaciology is ice dynamics. This branch studies the mechanical properties and dynamical responses which lead to estimations of ice deformation and glacial flow. The knowledge of ice dynamics is crucial in order to understand the chronology of an ice core, and further the flux of ice trough a glaciated landscape. The mass flux of ice is of importance with respect to sea level changes, and the study of ice flux through large glaciated catchments is of global importance.
Numerical modelling. Ice mass discharge into the ocean from large ice sheets as well as from glaciers and ice caps is substantially contributing to sea level rise. To understand their present and future contribution to the sea level rise we need to understand how the glacier dynamic and feedback mechanisms work. Numerical modeling is then a valuable tool to understand the complex interactions. Using full stokes models allows a fair description of the processes involved with ice flow and in the end enables future projections to some extent. The increase in velocity of outlet glaciers or ice streams is a major unknown today and modelling these ones is a great challenge.
The hydrological research focuses on problems concerning quantity and quality of surface and ground waters and on water and energy exchange at the land/atmosphere interface. Hydrological modelling and statistical downscaling support fundamental research. In more applied studies, the aim is to provide decision support in water management.
Surface and ground water in the drainage basin The drainage basin is a central concept in all hydrological, and many ecological, studies. Stream flow generation is governed by the landscape characteristics of the drainage basin, which also affect the biogeochemical processes governing water quality in surface waters as well as in soil and ground water. We study these processes by using e.g. tracer techniques. Water balance modelling is an important component in the quantification of runoff, which is the central issue for water provision and in problems of draught and flooding. Studies of the specific parts of and processes in the drainage basin are also carried out. Soil water and soil heat flows are modelled and we have a strong component of ground water modelling and modelling of solute transport.
Water pollution; environmental effects and measures Water management is the collective term used for synthesising studies with the aim of maintaining a suitable aquatic environment and water resources for future generations. We have several project aiming at measures for remediation of surface and ground waters. We also study climate impacts on the water systems. In these projects, the drainage basin is also the focal point and generic unity.
Exchange of energy and mass (water and carbon dioxide) between atmosphere and land surface The understanding of the climate system and its hydrological and meteorological processes is an important prerequisite for forecasting of climate change effects on our water resources. The exchange of energy, water vapour, and carbon dioxide between the atmosphere and the land surface are basic in this system and is studied in situ for both forest and agricultural lands.
Sustainable Water Resources
Water is a renewable resource as long as it is sustainably used. In many regions, water of appropriate quality is scarce and must thus be managed properly. Research for sustainable management calls for both basic and applied research in hydrology, engineering, socio-economic issues as well as decision-making processes.
Societies in all regions are dependent on a reliable supply of drinking water, industry on process water, and agriculture on water for crops. As a basis for planning and management, a hydrological model, describing the water balance on at least a monthly basis is a prerequisite. In the application of the models, a database on hydrological and climotological data is needed, calling for a monitoring system specifically adapted to the regional setting. As a result of scenarios produced with the hydrological model chosen, the need for facilities, such as dams, water distribution and treatment systems, etc. may be identified in order to assure appropriate volumes and quality. Flood risks can be assessed from statistical analyses of historical data and elucidated by the hydrological model. A hydraulic model can identify areas with risk for inundation. Having thus identified the framework for water supply management, the issue of water demand management needs to be addressed. Losses of water may occur in distribution systems, by unwise use of water and by plain neglect. A proper price of water helps to economize water use and keep demand on a reasonable level.
The upper Choluteca River basin The upper Choluteca River supplies water to the capital of Honduras, Tegucigalpa. The main problems for the capital are shortage of drinking water, bad water quality in the river and severe risk for flooding. The two first problems are related because all water is used for drinking purposes, turning the river into a principally sewage fed stream. Flooding is a result of hurricanes sometimes passing. Our research work in the basin is focused on building a database of hydrological and climatological data, including development of the monitoring programme and a hydrological model that can be implemented in the basin. A second line of research deals with water management. Sewage water treatment and dam operation in order to secure the water quality are included in this part. In Honduras, a large number of authorities are involved in various aspects of water use; energy, drinking water, water quality, flood management, making coherent action and access to data more difficult.
The meteorological research is focused upon the atmospheric boundary layer,
devoted to studies of the physical processes in the lowest few hundred metres or,
at most first few kilometres, of the atmosphere.
The research in boundary-layer meteorology concerns basic boundary layer studies
over land and water, as well as studies related to more applied aspects, such as
wind energy, noise propagation, and air pollution. Our main tools are
measurements with specialized equipment mounted at various heights on towers,
together with numerical models.
Boundary layer meteorology is devoted to studies of the physical processes in
the lowest few hundred meters or, at most first few kilometers, of the
atmosphere. The boundary layer acts as the link between the overlying atmosphere
and the underlying land or ocean surface. Here vertical transport of sensible
heat and water vapor takes place either from the ground surface up into the
atmosphere or, as the case may be, in the opposite direction. Also, and very
importantly, momentum is being brought down from the atmosphere to the ground,
so that the large-scale atmospheric motions undergo retardation, which means
eventual collapse of storms. These transports are all accomplished through the
action of irregular turbulent fluctuations in the atmospheric boundary layer.
These in turn are brought about by two mechanisms: (i) shearing instability of a
an air layer which is subject to retardation at the underlying surface and (ii)
convection, which, over land during the warm season, is the result of daytime
heating of the ground surface due to absorption of solar radiation. Also cold
air flowing over a much warmer ocean surface may give the same result.
Correct treatment of the physical processes in the atmospheric boundary layer is
of crucial importance for weather forecasting and for numerical simulations of
climate change. The lower part of the boundary layer is also the direct
atmospheric environment for humans, animals and plants living on the Earth's
surface. The ever present turbulence in the boundary layer causes dilution and
transport of every material that is released into it. Thus, for successful
abatement of air pollutants it is necessary to have deep knowledge of the
physical processes which cause this transport and dilution. For effective use of
wind energy, detailed knowledge of winds and turbulence is also needed.
Palaeontology is the study of the origin and evolution of the Earth’s Biosphere during its 4.500.000.000 year history, as represented by fossils of plants, animals, and other organisms. Palaeontology is thus an integral part of both biology and geology
Earth's history contains a record of catastrophic and gradualistic events on a scale which dwarfs the problems which our Biosphere faces today. The geological record adds the dimension of time to the evolutionary and environmental debate. The fossil biosphere is the arena for new evolutionary and environmental hypotheses; it is the testing ground for increasingly significant data concerning, for example, the early diversification of life and animal relationships.
Palaeontological research is by its nature interdisciplinary. The research within Palaeontology in Uppsala emphasizes the following topics: Early diversification of the unicellular (prokaryotic and eukaryotic) biota and ecological adaptation in the Proterozoic; Biodiversity of Precambrian organic-walled photosynthetic microbiota; Biological affinities of autotrophic microorganisms and their role in evolving ecosystems during the Cambrian metazoan radiations; The early fossil biosphere as related to the molecular biological record of living biota; Patterns of early metazoan diversification, in particular the so-called 'Cambrian Explosion; Exceptional preservation, especially the 'Sirius Passet' fauna; The phylogeny and palaeobiology of Early Palaeozoic brachiopods and molluscs; The fossil record as it relates to evolutionary theory; The interface between palaeobiology and the 'evolution of development'.
Seismology is our most important tool for elucidating the whole Earth. Analysis of seismic waves which have traveled through the Earth provides information both about structure and composition of the Earth at depth, and also about how the Earth’s crust and lithospheric plates move.
Structure From careful analyses of seismic waves we know that the Earth has an inner solid and outer liquid core, a stoney mantle and a thin crust. Similar studies can be done on a smaller scale, providing information about the structure of the crust, e.g. where oil can be found and how solid the rock under Forsmark is. In Uppsala we use tomographic and other methods, using signals both from earthquakes on the other side of the earth and small earthquakes in Sweden, to investigate structures in the crust and upper mantle below Sweden. Earthquake sources Earthquakes give us much information about the situation near the source. The orientation of the fault which has moved, and the direction and size of movement on the fault, tell us how the lithospheric plates are moving relative to each other, and on a smaller scale about movements in fault systems, pore water pressure and the distribution of stresses in the rock mass. Information about earthquake sources is also vital for increasing our understanding of how and why earthquake occur when and where they do. In Uppsala we deduce the Earth’s mechanical and dynamic properties from analyses of many individual Earthquakes. We look at earthquakes from volcanoes, from lithospheric plate boundaries and in the stable Swedish bedrock. Warning systems An important aim in seismology is to warn society about risks from earthquakes and related phenomena. Today we can predict volcanic eruptions rather well and Uppsala seismologists collaborate in providing eruption warnings on Iceland. Uppsala is also active in risk assessment in several developing countries, in e.g. Central America and East Africa.
Today’s wind power has come a long way regarding technique and scale, but it is still not competitive without subsidies or other financial support. Natural variations in wind speed makes it difficult to fully utilize installed power. Our cross disciplinary research strives to tackle these and other issues.
The increasing price of electricity is an advantage for wind power, but to become more profitable it has to be extremely cheap and reliable. Wind power is still a rather young source of electrical power and only wind turbines from the 1980s have had the time to show their reliability during their whole projected lifetime.
The ambition at the division for Electricity is to make wind turbines simpler, more efficient and more reliable (and thereby cheaper) with less impact on humans and the environment. The research is mainly focused on vertical axis wind turbines equipped with direct driven permanent magnet generators.
At the Department of Earth Sciences research within the wind energy program aims at getting meteorological information to be used for siting of wind power. This includes both mean wind and turbulence conditions.