MAIN AIR POLLUTANTS POLLUTANT SOURCES PARTICULATE MATTER CLEAR DAY PM-10 m PM-2.5 m POLLUTION The smaller the particle, the longer it remains suspended, and the higher the likelihood of lung penetration. DENVER, COLORADO, USA 1. 2. 3. 4. Sunlight dissociates NO2 O reacts with O2 to create O3 (O3 would normally be destroyed by NO) Hydrocarbons (pollution) can react with NO O3 levels reach high levels. STRATOSPHERIC OZONE IS GOOD! (absorbs ultraviolet radiation) TROPOSPHERIC OZONE IS HARMFUL Pollution in USA LESS DISPERSAL HIGHER CONCENTRATIONS OVER SMALLER AREA MORE DISPERSAL LOWER CONCENTRATIONS OVER LARGER AREA EFFECTS PRONOUNCED WHERE SOIL BASES ARE IN SHORT SUPPLY (eg. Canadian Shield) Figure 18.4 KOPPEN CLIMATE CLASSIFICATION Iquitos, Peru Timbo, Guinea SEE LETHBRIDGE CLIMOGRAPH FOR ANOTHER EXAMPLE! Denver, Colorado SEE PHOENIX, ARIZONA CLIMOGRAPH (Fig. 18.14) HUMID SUBTROPICAL CLIMATE Mobile, Alabama MARITIME CLIMATE Port Hardy, BC MEDITERRANEAN CLIMATE HUMID CONTINENTAL CLIMATE Des Moine, Iowa (only marginally humid) SUBPOLAR CLIMATE POLAR CLIMATE POLAR ICE CAP CLIMATE Eismitte, Greenland Climate Through the Ages Figure 19.4 Data important for estimating past climate include: lake bottom sediment, pollen in ice caves, fossil evidence, written documents, coral isotopes, calcium carbonate layers in caves, borehole temperature, and dendrochronology or tree ring data. These data have helped identify the Younger-Dryas cold spell that broke a warming trend in this current interglacial period. Milankovitch Theory of Climate Change Climate change may be driven by changes in earth's a) orbit (eccentricity), from ellipse to circle at 100,000 year cycles, b) wobble (precession), from the north pole pointing toward or away from the sun in June at 23,000 year cycles, and c) tilt (obliquity), from 22° to 2 4.5° at 41,000 year cycles. EFFECT OF MT PINATUBO ERUPTION Source: IPCC Source: IPCC Source: IPCC Ice core data Temperature, CO2 and CH4 are all in phase Are the gas concentrations a cause or an effect of warming or both ? 2xCO2 ENVIRONMENT Source: IPCC 1. Reduced Biodiversity (rapid change) 2. Sea level rise and coastal flooding (melting ice and thermal expansion) 3. Expansion of tropical disease range 4. Soil Moisture Decreases and Desertification ? 5. Increased frequency of heat illness (problem for the elderly) 6. Increased frequency of severe events? 7. Engineering problem of thermokarst (transportation and housing) 8. Affect on outdoor winter recreation and winter tourism 1. Increasing NPP? 2. Increased food production?: CO2 fertilization, range & growing season (depends on soil moisture/depth/nutrients) 3. Increased water-use efficiency 4. Increased nutrient-use efficiency? 5. High latitude warming (positive and negative) Source: IPCC