America’sEnvironmental Landscape

• What are the broad patterns of landforms, climate, hydrology, natural vegetation, and ecosystems of North America?

• How have these patterns helped shape human settlement?

Topography• Very large topographic regions

– Based on physical relief– Regions are generally oriented north-south

• Tectonics & Volcanism

Glaciation

Hydrology

Topography: Soils• Mixture of weathered rock, OM, water, air• Shaped & altered by the physical

environment over time• Described in terms of distinguishing

properties…– color – texture – structure – ability to hold water and air– degree of acidity or alkalinity

Where soils are well developed vertical zonation may occur producing distinct layers or soil horizons

Soils

Weather & Climate

• Geographic controls– Latitude

– Land-water relationship

– Relief (elevation)• Air pressure & orographic precipitation

– Air masses and wind systems

Latitude

• Temperature is a function of an area’s exposure to the direct rays of the sun

• Maximized exposure at equator; minimized at poles

• Yearly earth-sun relationship (seasonality)

Land and Water Relationship

• Land tends to heat faster and cool faster than water

• Annual temperature ranges

• Continentality

• Maritime influence

Relief

• Orographic Precipitation– Higher elevations are cooler than lower

elevations – Adiabatic cooling rate of rising air: 5.5º per 1,000’

• Temperature

Air Masses

North American Air Masses

Air Masses and Wind Systems

• North American wind patterns = distinct climatic patterns

• North American Pattern– Western US: topography is the key control– East: latitude is significant in determining

variations in temperature and precipitation

Precipitation Regime: Winter

Precipitation Regime: Summer

Climate Zones

• Based on Köppen Classification– Most widely used climate classification system

• Vegetation types are a direct response to climate

• Regional boundaries show temperature and precipitation associations with vegetation limits

PermafrostRegions

Biogeography & Ecology

Bioregions

Ecosystems & Watersheds

Mineral Resources

• Metallic Minerals• Fossil Fuels (oil, gas, and coal)

– Oil and Gas Fields– Coal

• Major Fields–Appalachian–Eastern Interior–Western Interior–Western

FOSSIL FUELS

Quick Reading

• Ratzel, F., Wissler, C., & Sauer C. O. Culture Area Research & Mapping.– A brief overview of combining geotechniques

and regional geography

Discussion Questions

How could North American environmental patterns affect human settlement?

Besides the ecoregion and biome concepts, can you think of any other technique to classify physical geography characteristics?

Related Books• Diamond, Jared. 1997. Guns, Germs, and Steel: The

Fates of Human Society. New York: W.W. Norton and Company.– Pulitzer Prize winning book by a converted geographer. It

discusses the human and environmental history of Earth in a lively manner.

• Marsh, William M. 2005. Landscape Planning: Environmental Implications, 4th ed. New York: John Wiley & Sons.– A guidebook of sorts, focusing on how different environmental

states affect land use planning in North America.• Orme, Anthony R. ed. 2002. The Physical Geography of

North America. New York: Oxford University Press.– 25 articles by well-respected authors detailing current

information about regional environments of North American systems.

WebSources

• Physical Geography Introduction/Overviewhttp://www.physicalgeography.net/home.html

• National Oceanic & Atmospheric Administration (US Department of Commerce)http://www.noaa.gov/

• Hurricane Informationhttp://hurricanes.noaa.gov/

http://cimss.ssec.wisc.edu/tropic/

• U.S. Global Climate Change Research Programhttp://www.usgcrp.gov/