Global Environmental IssuesMay 11, 2011Objectives: To develop an

understanding of Global Environmental Issues.

NO FIRST 5Agenda: NOTES

Slide 2

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.

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 balanceof our environment

Slide 4

Global Environmental Issues

From http://www.pref.kyoto.jp/intro/21cent/kankyo/contents_e/globe_prob/index.html

• Global Warming• Ozone Layer Depletion• Acid Rain• Deforestation• Loss of Biodiversity• Water Pollution• Desertification• Waste disposal

Slide 5

• Human activities are increasing the amount of greenhouse gases in the atmposphere, which cause more heat to be trapped

Global Warming

• 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.

• Greenhouse gases help to maintain the earth’s temperature at a level suitable to support life

Slide 6

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• 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

Development of Ozone Hole

Consequences of Ozone Layer Depletion• caused by

chlorofluorohydrocarbons (e.g. freon)

• effect is 30 years delayed • lets more uv light in • causes rise in skin cancer,

cataracts • weakens immune system • harms photosynthesizers

Ozone Level in North Americal

Slide 10

Acid Rain• The burning of fossil fuels leads to

atmospheric emissions of NOx and SO2

• 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– Causesacidification of lakes and other

waterbodies– Disturb wildlife – Cause the decay of building and other

structures– Impact on human health

Diagram of Acid Rain

Acid Rain Effects in U.S.

Acid Rain Effects in Europe

Effects of Acid Rain

• Acidification of lakes, streams, and soils

• direct and indirect effects (release of metals, e.g. Al; wash away of nutrients)

• Kill of wildlife (trees, crops, aquatic plants, and animals)

• Decay of building materials and paints, statues, and sculptures (e.g. Maya Ruins in Yucatan)

• Health problems (respiratory, burning skin and eyes)

Slide 15

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

May 12, 2011• Objectives: To develop a

better understanding of Environmental Issues.

• Question: What is an effect of the depletion of the ozone?

• Agenda: Notes/Article Review on Water Dumping

Slide 17

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

Slide 18

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

Slide 19

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

Slide 20

Waste Disposal• Waste disposal methods include:

– Open dumping and landfill– Ocean dumping– Exporting waste– Waste to energy plants

• Minimising the waste stream:– 3R’s: reduce, reuse, recycle– Composting– Waste to energy

• Hazardous waste disposal– Needs to be safely handled and disposed

of to minimise threats to the environment and human health

Slide 21

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

Slide 22

Ozone Layer Depletion

Ozone layer thickness measured in Dobson Units

Animation sourced from: http://www.epa.gov/ozone/science/hole/holeanim.html

Final 5• What are some problems

with loss of biodiversity?