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Chapter 1 (Introduction).pptx

  1. Environmental Change as a Disaster Risk (GeDM 505)
  2. 1.1 Environment Environment is: the total surrounding of an organism in a given area including the physical and non-physical surroundings. the conditions of an organism’s surroundings. a set of conditions and forces which surround and have direct influence on the organization/organism. the conditions that affect the behavior of somebody or something and/or the physical conditions that somebody or something exists in…the natural world in which animals and plants live.
  3. It, therefore, implies that environment is made up of all the physical visible and microscopic matters that affect the existence of organisms positively or negatively and an organism does not exist in isolation. It must co-exist with other matters. • The human dimensions of global environmental change must take as its point of departure the interaction between human activities and the Earth's physical, chemical and biological systems. • Consequently, a description of these systems and their processes is an essential part in understanding the global environmental change.
  4. • The total Earth system, from the center of the planet to the outer edges of its atmosphere, can be described in terms of a number of systems. • The simplest classification consists of two systems: the geosphere and the biosphere. • The geosphere includes the inanimate lithosphere (rocks), pedosphere (soils), hydrosphere (liquid water and ice), and atmosphere (the gaseous envelope surrounding the earth). • The biosphere is "the integrated living and life- supporting system comprising the peripheral envelope of Planet Earth together with its surrounding atmosphere so far down, and up, as any form of life exists naturally".
  5. • Hence the two systems are interwoven within the oceans and bodies of fresh water, on land, and in the atmosphere. • Homo sapiens is a living organism, whose activities take place within the geosphere and biosphere, contributing to global environmental change, and formed another geo-system called the anthroposphere (the built up environment). • Thus, anthroposphere is part of the environment that is made or modified by humans for use in human activities and human habitats. • Since the Earth is a sphere, these systems that surround the Earth can also be described as ‘spheres’, known as geospheres/earth spheres.
  6. • As human technology becomes more evolved, so do the impacts of human activities on the environment. Examples: deforestation for housing, extracting minerals, constructing cities/towns, establishing factories, etc. • These spheres all interact with one another, and are only separated for ease of study. • There is an intricate interaction among them and an impact on one sphere can have consequences on others. • The diagram below puts the pedosphere in the middle but in reality, there are lots of ways of interpreting these links.
  7. Interactive and complex processes linking the pedosphere with the atmosphere, biosphere, hydrosphere and lithosphere. Nature Education, 2012.
  8. 1.2 The Concepts of Environmental Change, Disaster, and Risk What is an environmental change? • Environmental change is a change or disturbance of the environment most often caused by human influences and natural ecological processes. • Global climate change has already had observable effects on the environment. • Some examples of environmental change include glaciers have shrunk, ice on rivers and lakes is breaking up earlier, plant and animal ranges have changed, contents of water and air have been changed through pollution, trees are flowering sooner, freshwater shortages, loss of biodiversity (with consequent changes to functioning of ecosystems), exhaustion of fisheries, etc.
  9. What is disaster? • Disaster is a serious problem occurring over a short or long period of time that causes widespread human, material, economic or environmental loss which exceeds the ability of the affected community or society to cope using its own resources. What is meant by environmental disaster? • An environmental disaster or ecological disaster is defined as a catastrophic event regarding the natural environment that is due to human activity. ... These disasters have included deaths of humans, livestock, wildlife, and plants, or severe disruption of human life or health, possibly requiring migration.
  10. • Examples of disaster resulting hazards include wildfires, landslides, floods, earthquakes, droughts, tornadoes, tsunamis, and volcanic eruptions. • Although the causes of these natural environmental hazards do not involve human activities, in some cases the effects are worsened by the influence of people. What is risk? • In simple terms, risk is the possibility of something bad happening. • Risk involves uncertainty about the effects/implications of an activity with respect to something that humans value (such as health, well-being, wealth, property or the environment), often focusing on negative, undesirable consequences.
  11. What is Environmental disaster risk? • Environmental disaster risk is the probability and consequence of an unwanted accident in the environment. • For example, because of deficiencies in waste management, waste transport, and waste treatment and disposal, several pollutants are released into the environment, which cause serious threats to human health along their way. This is referred to as environmental disaster risk.
  12. 1.3 Beginning Period of Large-scale environmental change • Scientists generally regard the later part of the 19th century as the point at which human activity started influencing the climate. But the new study brings that date forward to the 1830s. How has the environment changed over the past 100 years? • Over the last century, the average surface temperature of the Earth has increased by about 1.0oF. The eleven warmest years this century have all occurred since 1980, with 1995 the warmest on record. ... A warmer Earth speeds up the global water cycle: the exchange of water among the oceans, atmosphere, and land.
  13. How has the environment changed in the last 20 years? – Global temperature has risen six-tenths of a degree in those 20 years. – Population has increased by 1.7 billion people. – Sea levels have risen 3 inches and extreme weather in the U.S. has increased by 30 percent. – In Greenland and Antarctica, ice sheets have lost 4.9 trillion tons of ice.
  14. 1.4 Causes of environmental change • Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. • Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water. These negative impacts can affect human behavior and can prompt mass migrations or battles over clean water. • The causes of environmental change can be divided into two categories-natural causes and human- induced causes • Natural causes include volcanic eruptions, ocean currents, the Earth's orbital changes, solar variations and internal variability.
  15. • Anthropogenic causes for climate change are that humans are causing most of the current changes to climate by burning fossil fuels such as coal, oil, and natural gas. Human/Behavioral Causes of Environmental Change Behavior is: – the actions or reactions of a person or animal in response to external or internal stimuli – the manner in which one acts or behaves – the actions displayed by an organism in response to its environment – the manner in which something functions or operates – in object technology, the processing that an object can perform
  16. • Almost all human activity has some potential relevance to global environmental change. • Researchers in a number of fields have studied human-environment interactions, usually within the boundaries of single disciplines and almost always below the global level. • They have demonstrated that a complex of economic, technological, social, political, and cultural variables, sometimes referred to as driving forces, influences the human activities that proximately cause global change.
  17. • The driving forces can be roughly classified as follows: i. Population Growth: Each person makes some demand on the environment for the essentials of life—food, water, clothing, shelter, and so on. • If all else is equal, the greater the number of people, the greater the demands placed on the environment for the provision of resources and the absorption of waste and pollutants. • However, all else is not equal. For example, a new individual with the standard of living and technological base of an average North American would use about 35 times as much energy as an individual living at India's average standard— with a roughly proportional impact on the global environment. ii. Economic Growth: For the first time in human history, economic activity is so extensive that it causes environmental change at the global level; the prospect of further economic growth arouses concern about the quality of the global environment.
  18. • Economic growth necessarily stresses the environment, but the amount of stress from a given amount of economic growth depends, among other things, on the pattern of goods and services produced, the population and resource base for agricultural development, forms of national political organization, and development policies. iii. Technological Change: Technology can influence environmental change by finding new ways to discover and exploit natural resources or by changing the volume of resources required—or the amount or kind of wastes produced—per unit of output. • Technologies may either increase or decrease the impact of human activity on the environment, depending on the other driving forces, which determine which technologies are developed and used.
  19. iv. Political-Economic Institutions: The global environment responds to the actions of markets, governments, and the international political economy. • Markets are always imperfect, and the impact of economic activity on the environment depends on which imperfect-market method of environmental management is being used. • Governmental structure and policies can also have significant environmental consequences, both intentional and inadvertent. • And the international political economy, with its global division of labor and wealth, can promote environmental abuses, particularly in the Third World. • The effects depend on policy at the national level and on the behavior of particular economic actors.
  20. v. Attitudes and Beliefs: beliefs, attitudes, and values related to material possessions and the relation of humanity and nature are often seen as lying at the root of environmental degradation. • Such attitudes and beliefs probably have their greatest independent effects over the long-term, on the time scale of human generations or more. • Within single lifetimes, attitudes and beliefs can have significant influence on resource-using behavior, even when social-structural and economic variables are held constant. • Although each of these driving forces is important at certain times and under certain conditions, much remains unknown about what determines their relative importance, how they affect each other, and how the driving forces in particular places combine to produce global effects.
  21. • For example, various combinations of social conditions may lead to a single outcome, such as deforestation. • Single-factor explanations of the anthropogenic sources of global environmental change are apt to be misleading, because the driving forces of global change generally act in combination with each other and the interactions are contingent on place, time, and level of analysis. • Understanding the linkages is a major scientific challenge that will require developing new interdisciplinary teams. • The research effort should include studies at both global and lower geographic levels, with strong emphasis on comparative studies at local or regional levels with worldwide representation. • Research should address the same question at different time scales, examine the links between levels of analysis and between time scales, and explore the ways that the human forces that cause environmental change may also be affected by it.
  22. Brief Conclusion on Behavioral Causes of Environmental Change • Many of the most readily identified causes of environmental changes are human activities. • Major contributors to the accumulation of greenhouse gases in the atmosphere include the burning of fossil fuels for heating and energy generation and the use of chlorofluorocarbons (CFCs) as coolants and aerosols. • The burning of fossil fuels is also a major cause of acid rain, which is formed when airborne sulfur dioxide and nitrogen oxides combine with water vapor. • Air pollutants include ozone, carbon monoxide, lead, sulfur dioxide, nitrogen dioxide, and particulates—all by- products of industrial and energy-generation processes. • Stratospheric ozone thinning is believed to be a direct consequence of the accumulation of CFCs in the upper atmosphere.
  23. • Major threats to clean, fresh-water supplies include contamination not only from precipitation of chemical emissions that have accumulated in the atmosphere but also from agricultural runoff containing pesticides and fertilizers, from waste discharges into rivers, from salt used for highway deicing, from hazardous wastes disposed of improperly, and from leachate from municipal dumps. • Deforestation is the consequence both of converting forests to farmland and residential and business areas and of overharvesting timber. • Wetland loss results from the "reclamation" of wetlands for commercial development. • Desertification, the transformation of arable land into land on which crops will no longer grow, has a variety of causes, including overgrazing and the salinization of soil from excessive irrigation.
  24. • Since the human activities that are implicated in detrimental environmental change are aimed at satisfying human needs and desires, those activities can only be expected to increase as the population grows. • And population growth, worldwide, is expected to continue for the near future at least, at something like its current rate, which would yield 9.8 billion of the current number of 8 billion people in the middle of the twenty-first century. • Moreover, if present trends continue, the pressures on the environment are likely to grow faster than the population. • During the 20th century, worldwide energy consumption has increased by a factor of about 15 and the total population has increased by a factor of about 3.5, which is to say that, compared with 1900, there are about 3.5 times as many of us now and each of us uses, on average, 4 times as much energy.
  25. • There is now an enormous disparity between the per capita use of energy in the industrialized world and in developing countries; we can expect that the desire of the developing countries to close this gap will create a strong impetus to increase the average use worldwide. • In short, there is much evidence that human behavior can adversely affect the natural environment in a variety of ways and that the forces that motivate environmentally detrimental behavior are likely to become even stronger in the future. • There is a need to better understand the coupling of behavior and environmental change and how to mitigate the undesirable effects.
  26. 1.5 Consequences of Environmental Change • Increased heat, drought and insect outbreaks, increased wildfires, all linked to climate change/environmental change. • Declining water supplies, reduced agricultural yields, health impacts in cities due to heat, and flooding and erosion in coastal areas are additional concerns. • Climate change increases the risk of illness through increasing temperature, more frequent heavy rains and runoff, and the effects of storms. • Health impacts may include gastrointestinal illness like diarrhea, effects on the body's nervous and respiratory systems, or liver and kidney damage. • In general, the consequences of environmental change are very intricate and need collaborative efforts.