1. Ch. 2: The Changing Global Environment
Globalization and Diversity Rowntree, Lewis, Price, Wyckoff As modified by Joe Naumann, UMSL

2. Learning Objectives
Learn about the basics of Earth’s environmental systems to prepare for later chapters
Understand the following concepts, models, and terms
- Greenhouse Effect
- Green Revolution
- Prairie
- Steppe
- Subduction Zone
- Anthropogenic
- Bioregion
- Climograph
- Desertification

3. Global Climates: An Uncertain Forecast
Human settlement and food production are closely linked to local patterns of weather and climate
People in different parts of the world adapt to weather and climate in different ways
Climate links us together in our globalized economy
Opportunities for some
Hardship for others
Challenges in growing food

4. Four Laws of Ecology Apply
Everything is connected
Everything goes somewhere
Nature knows best
There’s no such thing as a free lunch

5. World Climate Regions
Weather: short-term, day-to-day expression of atmospheric processes
Climate: long-term, average conditions
Usually at least 30 years of daily weather data (temperatures and precipitation)
Climate regions: boundaries drawn around areas with similar average climate conditions
Helps us to make inferences about human activities and settlement
Example: desert hampers agriculture; adequate rainfall, warm temperatures permit farming

6. World Climate Regions - North & South America (Fig. 2.3)

7. World Climates Europe, Africa, Asia, Australia (Fig. 2.3)

8. Global Climates, cont.
Climographs: provide average high and low temperatures and precipitation for every month in an entire year – a very useful illustration
Graph form
Average high temperature (upper line)
Average low temperature (lower line)
Sometimes just the daily average for the month is shown
Average precipitation (bars)
The extremes are not shown.
Provides “Average Annual Rainfall” figure

9. Climograph: many only show the monthly average temperature
Average Precipitation
Average High Temperature
Average Low
Temperature
Average Annual Precipitation: 40 inches

11. Convectional Land is heated and heats the air which then rises
Rising air cools & water vapor condenses
When raindrops are heavy enough to overcome the updraft of rising air, there is precipitation

12. Cyclonic/Frontal
Warmer air is lighter than cooler air, so when two air masses come in contact, the lighter one rises above the cooler one.
Then there is cooling, condensing, and precipitation

13. Orographic
A moist air mass meets a mountain range, and it is forced up and cools.
Then follows condensing and precipitation on the windward side of the range. The leeward side receives little or no rain and has a dry climate.
On the west coast, the coastal range and the Sierra Nevada ranges demonstrate this.

14. Global Climates, cont. Global Warming
Human activities connected with economic development and industrialization affect the world’s climate
Anthropogenic (human-caused) pollution increases the natural greenhouse effect

15. Global Warming Causes of Global Warming
Natural greenhouse effects make the earth warm enough to support life
Beginning with Industrial Revolution in Europe and North America, greenhouse gases have increased dramatically, mostly from burning fossil fuels
Carbon dioxide (CO2); Chlorofluorocarbons (CFCs); Methane (CH4); Nitrous oxide (N2O) are the major greenhouse gases

16. Global Warming, cont. The Four Major Greenhouse Gases
Carbon Dioxide (CO2): makes up more than 50% of anthropogenic greenhouse gases; comes mainly from burning fossil fuels
Chlorofluorocarbons (CFCs): about 25% of human-generated greenhouse gases; come mainly from aerosol sprays, refrigeration, & air conditioning – also cause ozone depletion.
Methane (CH4): about 15%; caused by burning of vegetation, by-products of cattle & sheep digestion, leaking natural gas pipelines, and refineries
Nitrous oxide (N2O): 5%; caused by agricultural chemical fertilizers

17. Effects of Global Warming
Computer models and scientists are coming to agreement on effects
Average global temperatures will increase 2 °F to 4 °F by 2030 – more extreme & less predictable weather
The same amount of cooling caused the Ice Age
Major shift in agricultural areas
Wheat belt could become warmer and drier; lower grain yield
Canada and Russia could become warmer
Southern regions of the U.S. and Europe could become warmer and drier, requiring irrigation
Rising sea levels as polar ice-caps melt, endangering low-lying islands around the world, and coastal areas elsewhere

18. How can it be denied?

19. Globalization & Climate Change
International Debate on Limiting Greenhouse Gases
Rio de Janiero Earth Summit (1992)
First international agreement on global warming
167 countries agreed to reduce their greenhouse gas emissions by a specific target date
U.S., Japan, India, China failed to meet emissions reductions

20. Globalization & Climate Change
Kyoto Protocol (December 1997)
38 industrialized countries agreed to reduce their emissions of greenhouse gases to below 1990 levels
To take effect, countries emitting 55% of the world’s greenhouse gases must ratify it

21. International Debate - Limit Greenhouse Gases
Ratification of Kyoto Protocol will be difficult
Pres. Bush opposes; says complying will damage U.S. economy
Large developing countries (India, China) are not yet bound to reduce greenhouse gases, and would have an advantage
Pres. Bush believes more study is needed to support a link between human activities and global warming
Bush administration in 2004 only admitted that there “might be a connection.” World view: the USA has been “dragging its feet” on global warming.

22. Ratification of Kyoto Protocol will be difficult
Tensions between developed and less-developed countries
Unrestricted emissions in developed world created global warming problem; developed countries emit more than 50% of the world’s greenhouse gases
LDCs believe MDCs should curb their emissions, and help LDCs limit their emissions
LDCs fear that ratifying Kyoto Protocol will limit their development
LDCs’ emissions are currently relatively low

23. Human Impacts on Plants and Animals
Earth is unique because of the rich diversity of plants and animals – becoming less diverse!
Vegetation is the “green glue” that binds together Earth’s life and atmosphere
Vegetation is both a product of and an influence on climate, geology and hydrology
Humans play a big part in this interaction
Domestication of plants, animals
Endangerment of plants, animals
Changed natural pattern of vegetation on the land
Bioregion (Biome): an assemblage of local plants and animals covering a large area (e.g., tropical rainforest or grassland)

24. Bioregions: North & South America (Fig. 2.5)

25. Bioregions: Europe, Africa, Asia, Australia (Fig. 2.5)

26. Globalization of Nature
Tropical Forests and Savannas
Mostly found in equatorial climate zones
Covers around 7% of the world’s land area
Three-layered canopy
As one moves poleward, distinct dry season forms and tropical forest becomes more open
Farther poleward, grassland and savanna replace forest
Deforestation in the Tropics
Annually, an area of tropical forest the size of Wisconsin is denuded
Land cleared for wood sale, cattle grazing, and settlement purposes – forests may not be able to regenerate if too much is cut down
Native peoples who live there lose the most

27. Deserts and Grasslands
These are large areas of arid and semi-arid climate that lie poleward (north and south) of the tropics
Comprise one-third of the Earth’s land surface
Desert: areas receive less than 10 inches of rainfall a year
Prairie: North American grassland
Steppe: shorter, less dense grassland found in Russia and Southwest Asia
Desertification: the spread of desert-like conditions
Caused by poor agricultural practices on marginal land, overgrazing, build-up of salts in soil from irrigation & planting in the “fallow” year
UN estimates that 60% of the world’s rangelands are threatened by desertification

28. Temperate Forests
Large tracts of forests found in middle and high latitudes (nearer the poles)
Two major tree types dominate
Conifers or evergreens (pine, spruce, fir)
Deciduous trees that lose leaves in winter (hardwoods include elm, maple, beech, and many others)
In many regions, these forests have been cleared for agricultural purposes
Commercial logging interests place global pressure on forests
Clear cutting versus selective cutting controversy

29. Food Resources The Green Revolution: most work was with grains
Food production must double by 2025 to keep pace with expected human population growth rates
Every minute: 170 people are born, and 10 acres of existing cropland are lost
The Green Revolution: most work was with grains
Has increased global food production since the 1950s
Changes include the following:
Shift from mixed crops to monocrops – single crop fields – of high-yield, genetically altered seeds
Intensive application of water, fertilizer, pesticides
Intensification of farming through reduction in fallow periods, or field-resting time between planting seasonal crops

30. Green Revolution Second stage of Green Revolution since 1970s
New types of fast-growing wheat and rice specifically bred for tropical & subtropical climates
With irrigation, fertilizers & pesticides, farmers can grow 2 or 3 crops each year instead of just one
India doubled its food production between
Problems associated with Green Revolution
Heavy use of fossil fuels makes Green Revolution agriculture more vulnerable to oil price fluctuations
Environmental damage
Social costs, especially associated with the higher cost of this approach

31. Food Resources Problems and Projections
Local and regional problems are usually responsible for food unavailability
Poverty and civil unrest at local levels impede food distribution
Political problems are usually more responsible for food shortages as compared to natural events
Food distribution is highly politicized
Globalization is causing a worldwide change in food preferences
Implications of shifting from vegetarian to meat-based diet
Africa and South Asia are most threatened by food shortages
UN predicts that by 2010, almost 200 million in South Africa will suffer from chronic undernourishment

32. The “solid earth” isn’t so solid
Continental Drift
The “solid earth” isn’t so solid
Appears to be generated by heat-sustained convection cells in the interior (particularly the asthenosphere which is not solid)
Movement occurs where plate boundaries abut
Divergence – spreading along mid-ocean ridges which lie above and upwelling in the cell
Convergence (subduction) – colliding plates over the downward portion of a convection cell
Ring of Fire – largely an area of subduction

34. Movement

36. Tectonic Plates

37. Conclusions End of Chapter 2
Some environmental change is natural, some is anthropogenic
Globalization both helps and hinders world environmental problems
World’s nation-states more willing to sign environmental treaties (whaling, ocean pollution, fisheries, wildlife protection)
But superheated global economic activity aggravates global environmental problems
This theme reappears throughout the text
End of Chapter 2