Chapter 2 Weather Climate and Climate Change 2014 Pearson Education Inc Weather and Climate Weather day to day variations in temperature and precipitation Climate statistical summary of weather conditions through time 2014 Pearson Education Inc Solar Energy Solar energy drives our weather Powers circulation of atmosphere and oceans 2014 Pearson Education Inc Insolation Amount of energy intercepted by Earth Depends on two factors Intensity of solar radiation determined by angle of incidence Variation in duration of sunlight by season 2014 Pearson Education Inc Variations in Angle of Incidence Daily and seasonal variation Seasonal angle dependent on latitude Tilt of Earth s axis 23 5 2014 Pearson Education Inc Total Insolation Total amount of solar radiation from seasonal changes in Length of daylight Distance from the Sun Tropical areas High latitudes 2014 Pearson Education Inc Earth s Orbit Around the Sun 2014 Pearson Education Inc Variation in Solar Radiation 2014 Pearson Education Inc World Temperatures January 2014 Pearson Education Inc World Temperatures July 2014 Pearson Education Inc Greenhouse Effect Greenhouse gases Carbon dioxide CO2 Ozone O3 Methane CH4 Water vapor Human activities are increasing the amount of CO2 and methane in the atmosphere 2014 Pearson Education Inc Greenhouse Effect 2014 Pearson Education Inc Urban Heat Islands 2014 Pearson Education Inc Relative Humidity Relative humidity actual water content of air expressed as percentage of what air could hold Cooling air causes increase in relative humidity Cooling beyond saturation results in condensation clouds 2014 Pearson Education Inc Three Types of Precipitation The movement of air causes precipitation in three ways Convection Orographic uplift Frontal uplift 2014 Pearson Education Inc Convectional Precipitation Adiabatic cooling cooling of warmed air as it rises 1 C per 100 meters 5 5 F per 1 000 feet 2014 Pearson Education Inc Orographic Precipitation Air forced to rise over mountains Adiabatic cooling from expansion Descent on leeward side Decrease in relative humidity Leeward side of mountains much drier 2014 Pearson Education Inc Rain Shadow 2014 Pearson Education Inc Frontal Precipitation Front boundary between two large air masses In North America Continental polar air cold Maritime tropical air warm Dense cold air below warm less dense air above Cold air advancing cold front Warm air advancing warm front 2014 Pearson Education Inc Fronts 2014 Pearson Education Inc Fronts and Weather 2014 Pearson Education Inc Climate Summary of weather over a long period Changes over time Two measures determine climate type Precipitation Temperature 2014 Pearson Education Inc Air Temperature Changes with elevation 6 4 C per 1000 meters 3 5 F per 1 000 feet Affected by Topography Proximity to oceans Water availability 2014 Pearson Education Inc Vertical Climate Zones 2014 Pearson Education Inc Precipitation Extreme variability over time and space Importance of regularity of rainfall Rain and snow total collected along with snow texture 2014 Pearson Education Inc Average Annual Precipitation Worldwide 2014 Pearson Education Inc Classifying Climates the K ppen System Wladimir K ppen German climatologist 1918 K ppen used distribution of plants to draw boundaries between climate regions instead of just raw temperature and precipitation data 2014 Pearson Education Inc K ppen Climate Classification 2014 Pearson Education Inc World Climates 2014 Pearson Education Inc Humid Low Latitude Tropical Climates A 2014 Pearson Education Inc Dry Climates 2014 Pearson Education Inc Warm Mid Latitude Climates C 2014 Pearson Education Inc Warm Mid Latitude Climates C 2014 Pearson Education Inc Cold Mid Latitude Climates D 2014 Pearson Education Inc Cold Mid Latitude Climates D 2014 Pearson Education Inc Polar Climates E 2014 Pearson Education Inc Polar Climates E 2014 Pearson Education Inc Climate Change over Geologic Time Quaternary Period most recent 2 million years Alternating cool and warm periods Pleistocene glaciations Melting of last ice sheets c 7000 B C Recent change last 1 000 years Medieval Warm Period A D 800 1000 Little Ice Age 1500 1700 2014 Pearson Education Inc Natural Causes of Climate Variation Astronomic factors Variations in Earth s revolution around the Sun Sun spots Geologic processes Continental drift Shifting wind pressure bands Formation of mountain ranges 2014 Pearson Education Inc Human Causes of Climate Variation Human modification Altering the atmosphere Removing vegetation 2014 Pearson Education Inc Global Warming Twentieth century warming 1 C 1 8 F Link with increased carbon dioxide CO 2 2014 Pearson Education Inc Global Warming Evidence of global warming Computer models Historic climate data Consequences of global warming Rise in sea level Decrease in water supply in some regions 2014 Pearson Education Inc End of Chapter 2 2014 Pearson Education Inc
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