Global Environmental Issues

Transcription

1 Global Environmental Issues

2 Purpose of this material The environment encompasses the whole of life on earth and the complex interactions that link the living world with the physical world. In a general sense, this covers everything contained within the air, land and water. Sudden and dramatic natural changes to the environment have occurred, and continue to occur, which have the potential to upset the whole balance of the Earth's ecosystem. Significant environmental issues cause impacts throughout the world. This presentation aims to inform people on the global environmental issues. Prepared June 204 Slide 2

3 What is the Environment? The environment encompasses the whole of life on earth and the complex interactions that link the living world with the physical world In a general sense, this covers everything contained within the air, land and water Time also is a key factor as historic issues have an influence on the status of the environment - locally and globally, both now and in the future. Prepared June 2004 Slide 3

4 Environmental Change Sudden and dramatic natural changes to the environment have occurred in the distant past, but only relatively recently has one species had the potential to upset the whole balance of the Earth's ecosystem The global population has risen dramatically during the last century The rise of industry and its rapid expansion has been a major source of pollution. This has caused changes in the balance of our environment Prepared June 2004 Slide 4

5 Global Environmental Issues From Global Warming Ozone Layer Depletion Acid Rain Deforestation Loss of Biodiversity Water Pollution Desertification Waste disposal Invasive Species Prepared June 2004 Slide 5

6 Global Warming Greenhouse gases help to maintain the earth s temperature at a level suitable to support life Human activities are increasing the amount of greenhouse gases in the atmosphere, which cause more heat to be trapped Predicted effects of global warming include: Higher sea levels Higher temperatures Variable climatic conditions These changes are expected to cause a significant impact on agriculture and ecosystems. Prepared June 2004 Slide 6

7 Ozone Layer Depletion The ozone layer protects the earth from harmful ultraviolet (UV) light The use of chlorofluorocarbons (CFCs) and other ozone depleting substances as refrigerants, solvents and insulation is destroying the ozone layer A hole is observed over Antarctica every autumn PLAY Depleted ozone levels cause the following impacts: Increased penetration of UV light to earth Increased risks of skin cancer and eye diseases Damage to agricultural crops Disruption to marine food chains Prepared June 2004 Slide 7

8 Acid Rain The burning of fossil fuels leads to atmospheric emissions of NO x and SO 2 These gases react with water and oxygen to make sulfuric and nitric acids. Sunlight increases the rate of these reactions Rain, snow and fog can be polluted with these acidic compounds, which is then deposited at the earths surface The deposition of acids can: Damage forests and soils Causes acidification of lakes and other waterbodies Disturb wildlife Cause the decay of building and other structures Impact on human health Prepared June 2004 Slide 8

9 Deforestation The deforestation of tropical rainforests is a major global problem-each year millions of hectares are lost Deforestation rates in some countries continue to increase despite worldwide pressures Rainforests are destroyed for wood products, and to make way for agricultural activities, mining and dams The impacts of deforestation include: Loss of livelihood for local inhabitants Variable environmental conditions (susceptability to flood, aggravated droughts, soil erosion etc) Loss of biodiversity and disturbance to ecosystems Loss of carbon sink Prepared June 2004 Slide 9

10 Loss of Biodiversity Biodiversity has three key components: Genetic diversity Species diversity Ecological diversity Approximately 2.1 million species are known to exist, but up to 50 million still to be discovered Biodiversity is important for food, drugs, maintaining ecological stability, aesthetic and cultural benefits Natural causes and human activity can threaten biodiversity The loss of biodiversity means ecosystems are destabilised, vital resources are lost and genetic variation is reduced Prepared June 2004 Slide 10

11 Water Pollution A change in water quality that impacts on living organisms Types and effects of water pollution include: Infectious agents, such as typhoid, cholera Nutrients and eutrophication Toxic materials, through mining Organic chemicals Sediments can disrupt aquatic ecosystems Prepared June 2004 Slide 11

12 Desertification Removing ground cover and degrading fertile land initiates desertification Water washes away nutrients, the land becomes inhospitable The process is accelerated by expanding populations and the need to overuse fragile areas of land Prepared June 2004 Slide 12

13 Waste Disposal Waste disposal methods include: Open dumping and landfill Ocean dumping Exporting waste Waste to energy plants, also known as incinerators Minimizing the waste stream: 3R s: reduce, reuse, recycle Composting Waste to energy Hazardous waste disposal Needs to be safely handled and disposed of to minimize threats to the environment and human health Prepared June 2004 Slide 13

14 Invasive Species Species that are not from the area they are inhabiting. They have been introduced to a new area, maybe by accident (brought on a ship) or on purpose (brought to an area to help with another problem). They use up resources that the indigenous species need, so the native species starve, die, or have to move to another location. Prepared June 2004 Slide 14

15 Environmental Management Environmental pollution is a serious burden on our ecosystems and finances world-wide Administrations, commercial organizations and individuals are affected by environmental change and its associated dangers, long-term effects and liabilities Both legislative obligations and voluntary mechanisms can address the environment and to integrate it into the mainstream of business activity Consequently, environmental management is a crucial part of all organizations' operations Prepared June 2004 Slide 15

16 Loudoun s Top Environmental Issues 10. Unsustainable Agriculture 9. Global Climate Change 8. Ocean Pollution 7. Air Pollution 6. Threat of Disease 5. Water Quality AND Quantity 4. Invasive Plants & Animals 3. Habitat: loss, degradation & fragmentation 2. Human Overpopulation 1. Apathy Do you care? What will you do to make a difference? Prepared June 2004 Slide 16