Presentation on theme: "University of Khartoum Institute of Environmental Sciences Dip/ M.Sc in Enviromental Sciences Fundamentals of Environmental Science By: Dr. Zeinab Osman."— Presentation transcript:
University of Khartoum Institute of Environmental Sciences Dip/ M.Sc in Enviromental Sciences Fundamentals of Environmental Science By: Dr. Zeinab Osman Saeed
Modelling Lecture nu 8
Scientific modelling Scientific modelling is the process of generating abstract, conceptual, graphical and/or mathematical models. Science offers a growing collection of methods, techniques and theory about all kinds of specialized scientific modelling. Also a way to read elements easily which have been broken down to the simplest form.conceptualgraphicalmathematicaltheory
Modelling Modelling is an essential and inseparable part of all scientific activity, and many scientific disciplines have their own ideas about specific types of modelling.
Model A model is a simplified abstract view of the complex reality. A scientific model represents empirical objects, phenomena, and physical processes in a logical way.
Modelling as a substitute for direct measurement and experimentation Models are typically used when it is either impossible or impractical to create experimental conditions in which scientists can directly measure outcomes. Direct measurement of outcomes under controlled conditions will always be more accurate than modeled estimates of outcomes. When predicting outcomes, models use assumptions, while measurements do not. As the number of assumptions in a model increases, the accuracy and relevance of the model diminishes.
Simulation A simulation is the implementation of a model over time. A simulation brings a model to life and shows how a particular object or phenomenon will behave. It is useful for testing, analysis or training where real-world systems or concepts can be represented by a model.simulation
Structure Structure is a fundamental and sometimes intangible notion covering the recognition, observation, nature, and stability of patterns and relationships of entities. Structure
The process of generating a model Modelling refers to the process of generating a model as a conceptual representation of some phenomenon. Typically a model will refer only to some aspects of the phenomenon in question.
The process of evaluating a model A model is evaluated first and foremost by its consistency to empirical data; any model inconsistent with reproducible observations must be modified or rejected. However, a fit to empirical data alone is not sufficient for a model to be accepted as valid.
The process of evaluating a model Other factors important in evaluating a model include: Ability to explain past observations Ability to predict future observations Cost of use, especially in combination with other models Refutability, enabling estimation of the degree of confidence in the model Simplicity, or even aesthetic appeal
Visualization Visualization is any technique for creating images, diagrams, or animations to communicate a message. Visualization through visual imagery has been an effective way to communicate both abstract and concrete ideas since the dawn of man. Visualization
Ecosystem model Ecosystem models, or ecological models, are mathematical representations of ecosystems. Typically they simplify complex foodwebs down to their major components or trophic levels, and quantify these as either numbers of organisms, biomass or the inventory/concentration of some pertinent chemical element (for instance, carbon or a nutrient species such as nitrogen or phosphorus).mathematicalecosystemsfoodwebstrophic levels
Complexity Ecosystem models are a development of theoretical ecology that aim to characterise the major dynamics of ecosystems, both to synthesise the understanding of such systems and to allow predictions of their behaviour (in general terms, or in response to particular changes). theoretical ecologydynamicspredictions
Complexity Because of the complexity of ecosystems (in terms of numbers of species/ecological interactions), ecosystem models typically simplify the systems they are studying to a limited number of pragmatic components. These may be particular species of interest, or may be broad functional types such as autotrophs, heterotrophs.In biogeochemistry, ecosystem models usually include representations of non-living "resources" such as nutrients, which are consumed by (and may be depleted by) living components of the model. functional typesautotrophsheterotrophs
Example of scientific modelling. A schematic of chemical and transport processes related to atmospheric composition.
Environmental Perception & Values Many of the debates and controversies regarding management of natural resources stem from people’s differing environmental perceptions and values – and in some cases the different perceptions they have of other people’s values.
Environmental Perception & Values Scientists work to identify and better understand how people experience the natural environment, what prompts those experiences, and how important they are to people. They seek to find out which attributes of places are important to people. One of the goals driving research is to help natural resource managers understand that it is important to consider people’s experiences of nature when establishing policies and practices.
Natural-environment perception & preference Natural-environment perception & preference What are the ideal number and kinds of trees in a community park, from the human perspective? Can there be too many trees? Too few? Research showed that urban people’s perceptions of landscapes are influenced by the types, sizes, and number of trees and other plants.
Values & meaning of places People have very strong feelings for and attachments to places and environments. This holds true for those who live in an area, people who visit it, and even those who may have never visited it.
Demographic differences and diversity Demographic differences and diversity As urban populations become more diverse, managers of natural resources across the urban-to-rural spectrum need to be able to anticipate and respond to their needs. People of different backgrounds may experience the environment differently. Age, race and ethnicity, income, education, and other factors influence how people experience and are affected by the environment.
Demographic differences and diversity Demographic differences and diversity People of different backgrounds may experience the environment differently. Certain individuals or groups might have unique needs, or because they are in a minority, may not have their needs voiced in the larger public context of resource management and planning.