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Global Climate SystemsI. Earth’s Climate
A. Past ClimateB. Present Climate and Classification
1. Climate components2. Classification 3. Köppen Climate Classification4. El Nino
III. Global Climate ChangeA. Global Warming
I. Earth’s Climate
Climate is weather over timeClimatology is the study of climateClimatic regions are areas with weather statistics that are similar over time
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Past Climate
How do we know about past climatic patterns?Glacial Ice DepositsBiological Marine SedimentsInorganic Marine Sediments Geological Proxy DataBiological Proxy Data
Past ClimateIce ages are intervals of time when large areas of the surface of the globe are covered with ice sheets (large continental glaciers).
Most recent Ice Age occurred during the Pleistocene (2,000,000 to 14,000 years ago).
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Past ClimateWhy did the Ice Age occur?
• changing continental positions • reduction of CO2 in the atmosphere • changes in the Earth's orbit every 95,800 years
(Milankovitch Orbital Theory of Glaciation)
Past Climate
Columbian Mammoth
Dire Wolf
Saber Toothed Cats
Harlan’s Ground Sloth
American Lion
Short Faced Bear
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Earth’s Present ClimateClimate Components
Climate Components: InsolationTemperaturePressureAir MassesPrecipitation
Earth’s Present ClimateA. Climate Components
Precipitation
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Earth’s Present Climate A. Climate Components
Types of Climate Classification:Genetic classification: Classification based on causative factors (things like air masses and global circulation)Empirical classification: Classification based on temperature and precipitation data.
Earth’s Present Climate 2. Classification of Climatic Regions
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Earth’s Present Climate3. Köppen Climate Classification System
Weather data used to create the Köppen Climate Maps:Average monthly temperaturesAverage monthly precipitationTotal annual precipitation
Earth’s Present Climate3. Köppen Climate Classification System
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Earth’s Present Climate 3. Köppen Climate Classification System
Tropical Climates (A) – equatorial regions, humid, warm
Earth’s Present Climate 3. Köppen Climate Classification System
Dry Arid and Semiarid Climates (B) - deserts and steppes; arid and semiarid regions
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Earth’s Present Climate 3. Köppen Climate Classification System
Mesothermal Climates (C) – humid subtropical, Mediterranean, and marine west coast regions
Earth’s Present Climate3. Köppen Climate Classification System
Mediterranean Climates (Cs)
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Earth’s Present Climate 3. Köppen Climate Classification System
Microthermal Climates (D) – humid continental, subarctic regions
Earth’s Present Climate 3. Köppen Climate Classification System
Polar Climates (E) - polar regions
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Earth’s Present Climate 3. Köppen Climate Classification System
Highland Climates (H) – Found in areas with moderate to high temps., but temperatures here are low due to elevation.
Earth’s Present Climate 4. El Nino Southern Oscillation (ENSO)
Occurs when in air pressure over the Pacific changes causing the trade winds to change direction. Water intensification and thunderstorms are in turn brought to the west coast of continents.Occurs every 3-5 years.
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Earth’s Present Climate4. El Nino Southern Oscillation (ENSO)
Earth’s Present Climate4. El Nino Southern Oscillation (ENSO)
Gobal Climatological Effects of El Niňo
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Global Climate ChangeA.Global Warming
Refers to short-term increases in global temperatures caused by human actions.Forced fluctuations in climate change are due to human activities.Unforced fluctuations are natural changes in global climate.IPCC states that global warming can be attributed to human activities (forced fluctuations).
Global Climate ChangeA. Global Warming
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Global Climate ChangeA. Global Warming
Radiatively active gases that influence global warming:
Carbon dioxide (CO2)Methane (CH4)Nitrous oxide (N20)Chloroflourocarbons (CFCs)Water vapor
Global Climate ChangeA. Global Warming
Impact of Global Warming:World food supply changesNatural ecosystems changesMelting glaciersIncrease in sea level
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Global Climate ChangeA. Global Warming
Figure 10.32
Antarctic Ice Disintegration
Global Climate ChangeA. Global Warming
Political Actions:Development of the Kyoto Protocol in 1997.Forces more developed countries to reduce greenhouse gas emissions collectively by 5.3%United States goal of 7.0% will not be met because President Bush has abandoned the Kyoto Protocol under concerns for the economic cost of the emissions reduction.