Physical Geography (GEOG 1301.01)

Chapter 10: Global Climate Systems

· Understand what “climate” is and what components of the earth’s spheres determine climate.

· Learn about the different classification of climate and identify those of the continental US.

· Identify and explain causes and potential consequences of future climate patterns

Important Concepts

Difference between weather and climate: Day to day conditions versus average over time (variability and extreme events.) Location and movement versus pattern and region (and location and movement also!- think through this so that you do not become confused!) Climate is tied to location. Koppen climatic regions use temperature and precipitation data.

Climate Linkages to know:

· West African monsoons and Atlantic hurricanes

· El Nino tied to drought-breaking rains in American West, flooding (Europe) and drought in Australia and Southeast Asia.

· Global climate change may be producing:

· record global temperatures

· glacial ice melt

· changing soil-moisture conditions

· affecting crop yields

· disease patterns

· species distribution

· reef and fisheries health

· permafrost thawing.

Changes in climate and natural vegetation during the next 50 years may exceed total of all changes since peak of last ice age (18,000 years ago.)

Weather elements that combine to produce climates: Insolation, Temperature, Humidity, Seasonal Precipitation, Atmospheric Pressure, Winds, Air Masses, Weather disturbances and Cloud Coverage.

Climate Components: Insolation, Temperature, Pressure, Air Masses and Precipitation

Climate is a conceptual, statistical construction from these measured weather elements.

Climate Controls: http://www.cla.sc.edu/geog/faculty/carbone/modules/mods4car/ccontrol/

PRECIPITATION IS THE KEY CLIMATE CONTROL FACTOR.

Deserts and drought areas are dominated by subtropical high-pressure cells.

Wet climates influenced by equatorial low pressure and ITZC (intertropical convergence zone.)

Temperature and precipitation (empirical) are the keys to climate classification (see Figure 10-3).

Genetic Classification based upon causative factors and empirical based upon statistical data.

Koppen-Geiger Climate Classification: Average monthly temperature, monthly precipitation and total annual precipitation.

Climate Designations: Know page 267-68 and review Continental US (Figure 10-4 and 10-5.)

Cfa and Cwa climates support large populations: Where are they?

Compare US and China climates. Consider population and climate.

Global Climate Change

Past 2 decades dominated by record-high global temperatures. Human activities are enhancing natural greenhouse effect. Climate trends come from forced fluctuations (human) and unforced fluctuations (natural.)

Global Warming: http://www.globalwarming.org/

Paleo-climatology:

http://www.ngdc.noaa.gov/paleo/globalwarming/home.html

Carbon Dioxide: CO2 (64% of warming trend and increasing .5%/year) and H2O vapor are the principal radiatively active gases (causing greenhouse effect.)- Transmit heat but delay heat-energy loss to space. We aggravate this by burning of fossil fuel and deforestation (most in developing countries.) What are some of the reasons for conflict?

Methane and Other Greenhouse Gases: Organic from livestock and rice fields. Responsible for 19% of atmospheric warming (Increase > 1%/ year.) Nitrous Oxide from fertilizer is third and CFCs are fourth (also cause ozone depletions.)

Climate Models and Future Temperatures: GCMs, Warming range from 3.6 to 6.3 degrees. Predicts high latitude warming.

Consequences of Global Warming: Regional changes in temperature, precipitation, soil moisture (10% less) and air masses. Monoculture agriculture high risk. Need more energy, water and resources to adapt. Climate shift of 90 to 350 miles toward the poles. Major species redistribution (30% change in forest cover.) Health impacts include malaria, yellow fever, etc all at subtropical and mid-latitude areas.

More plant-life: http://news.nationalgeographic.com/news/2003/06/0605_030605_climatechange.html#main

Climate and Disease:

http://news.nationalgeographic.com/news/2002/09/0920_020910_climatedisease.html

Melting Glaciers, Ice Sheets and Sea Level: Concern is glacial melt and continental ice sheets. Already up 4-8 inches and estimate at 4-20ft. Significant temp increase at 1,000 ft ocean depths. Thermal expension contributes to 125% of sea-level rise.

Key Terms: Climate, climatic regions, genetic and empirical classification, climograph & GCM

Assignment:

Questions: 1, 4, 6, 10, 22, 23 & 24

Definitions: climatic regions, ITCZ (Chapter 6) & GCM

DO THIS!!!!

GIS Climate Map Exercise:

Task: Create a map of climate zones for Texas.

1. Go to this web site: http://www.geographynetwork.com/
2. Click on “ArcExplorer Web”
3. At the “Load Map” window choose, “Services from other Internet Servers”
4. Pull down “Look in” and choose “ESRI” (first one)
5. Click “OK”
6. Add, “ESRI_Precip_Yr” and “ESRI_Temp_Yr”
7. Set “Transparency” on “ESRI_Precip_Yr” to 30% (hit “Refresh Map” button)
8. Check in the box in front of the 2 map layers to turn them on (hit “Refresh Map” button)
9. Answer these questions (write up and give me) based upon what you see:

• What are the potential climate classes for Texas?
• How would you describe precipitation and temperature regimes in Texas?
• How do these relate to the climate of Texas?

ANNOUNCEMENT: Test 2 on Monday, March 29, 2004