11 9 15 11 11 15 11 13 15 and 11 16 15 Dr Frauenfeld Chapter 10 Global Climate Systems b Climate refers to the average weather conditions over a long period of time 30 years i Based on temperature precipitation etc ii Helps to determine global distribution of ecosystems biomes iii Pressure affects precipitation iv Air Masses affects precipitation v Precipitation Affects moisture available vegetation and animals 4 mechanisms I Weather vs Climate a Weather short term conditions i Temperature ii Humidity iii Cloudiness iv Precipitation v Pressure vi Winds II Earth s Climate System and It s Classification a Climate Components Insolation Latitude affects temperature i ii Temperature four principle controls 1 Latitude 2 Elevation 3 Ocean Land Differences 4 Cloud Cover 1 Convergent 2 Convectional 3 Orographic 4 Tropical b Generalizations about Precipitation i Equatorial Region wet 1 Convergence of the trade winds 2 Lots of Convection heating 3 Ample moisture available oceans and coasts ii Subtropics dry 1 Sinking 2 Hadley cells produce a zone of high pressure iii Mountains 1 Wet climate on the windward side 2 Dry climate on the leeward side 11 9 15 11 11 15 11 13 15 and 11 16 15 Dr Frauenfeld iv Continental Interiors 1 Dry far away from moisture c Four Types of Precipitation Patterns Temporal i Uniform all months about equal amounts doesn t have to be a large amount ii Summer Max iii Winter Max More of a Summer Minimum Caused by the subtropical getting very large 11 9 15 11 11 15 11 13 15 and 11 16 15 Dr Frauenfeld iv Double Maximum spring and fall typically Caused by migration of the ITCZ d Climatic Relationships No precipitation variability in high latitudes because cold air is dry 11 9 15 11 11 15 11 13 15 and 11 16 15 Dr Frauenfeld e Idealized Global Climate f Climate Classifications i Genetic Classifications 1 Based on forcing factors a Net Radiation Insolation b Thermal Regime Hot or Cold c Air Masses ii Empirical Classifications Doesn t explain why 1 Based on actual data a Temperature b Precipitation 11 9 15 11 11 15 11 13 15 and 11 16 15 Dr Frauenfeld III Five Climate Regions of the World a Tropical three subtypes i Tropical Rain Forest 1 Wettest 2 On Equator 3 Constantly moist year round afternoon thunderstorms 4 Huge water surpluses i e the Amazon River 5 Lush evergreen broadleaf trees ii Tropical Monsoon 1 Along coastal areas 2 Some periods of dry 3 Similar to tropical rainforest but have a dry season at least one month has to be dry occurs when the ITCZ is not overhead 4 A monsoon is a seasonal reversal of the winds a During the wet season winds blow from the ocean b During the dry season winds blow from land iii Tropical Savanna 1 Buffer zone transitional climate 2 North South of tropical rainforests 3 Distinct wet and dry seasons of approximately equal length 4 Greater annual temperature variability 11 9 15 11 11 15 11 13 15 and 11 16 15 Dr Frauenfeld b Mesothermal Climates Mild Winter i Midlatitude mild winter 1 Warm and temperate 2 True Seasonality ii Regions Determined By 1 Changing Air Masses mT cP etc 2 Midlatitude Wave Cyclones 3 West Coast East Coast Differences 4 Decreasing Temperatures as you move Poleward iii Three Subtypes 1 Humid Subtropical a Hot Summer Climates i Moist year round summer convection winter frontal lifting b Winter Dry Climates i Monsoonal conditions ii Ten times more rain in the summer than in the winter 2 Marine West Coast Climates a Pacific Northwest U S Canada b Northern Europe c mP Air Masses cool moist unstable d Year round moisture e Surprisingly mild winters 0 cooler summers 3 Mediterranean Dry Summer Climates a Dry summers expansion of subtropical high i e cT conditions from Sahara Desert expand over Europe b Winters are wet c Also caused by cold ocean currents California and Chile c Microthermal Climates In the middle and high latitudes i General Characteristics 1 Cold long winters 2 Hot to cool summers going South to North 3 Year round moisture however there is a small monsoonal region in Asia that has a dry winter 4 There are NO microthermal climates in the Southern Hemisphere This is because there are no land masses at the latitudes where Microthermal Climates occur ii Four Subtypes 1 Humid Continental Hot Summer Climates a Hot summers and moderate winters b U S Midwest to NE c Moist year round Summer convection Winter Midlatitude Wave d Cyclones In NE China there is a monsoonal moisture regime so they have dry winters Because they are downwind from Siberia 2 Humid Continental Mild Summer Climates a Cooler than the hot summer 11 9 15 11 11 15 11 13 15 and 11 16 15 Dr Frauenfeld b Milder 3 Subarctic Cool Summer Climates In North America most of Alaska and Canada Boreal Forest In Eurasia Northern Europe and most of Russia Taiga a b c Large temperature seasonality d Year round moisture but very low amounts 4 Subarctic Very Cold Winter Climates a Only in Eastern Russia b Extremely cold winters 90 F mild summers c Extreme seasonality up to a 63 C 113 F range in Temperature d Polar and Highland Climates i General Characteristics 1 No true summer even during 24 hours of daylight temperatures are 10 C 50 F 2 Too cold for trees North of Tree Line 3 Extremely low moisture frozen deserts ii Two Subtypes 1 Tundra Climate a Summer barely above freezing b 8 10 months of snow covered ground c Low growing vegetation when snow melts lichens mosses and sedges d Extensive Permafrost permanently frozen soil only the top layer of soil thaws during summer leads to standing water because the water can t drain Ice Cap and Ice Sheet Climates a Northern Hemisphere Interior Greenland and Arctic Ocean freezes completely during winter half melts during the summer Milder than Antarctica because heat under the ice over the Arctic Ocean 2 b Southern Hemisphere Virtually all of Antarctica Ice is 4000m 2 5 miles thick in Eastern Antarctica i ii Very high elevations highest continent iii Windiest place on Earth iv Driest Place on Earth v Coldest Place on Earth 1 Average Winter Temp 34 C 2 Max Summer Temp 7 C 3 Lowest Temp ever recorded 129 F c Characteristics i The average temperature is below freezing each month ii The annual precipitation is between 2 5 inches 5 12cm lowest specific iii Growth of the ice sheet is mainly through deposition Caused by really humidity on Earth low temperatures e Deserts Arid and Semiarid Climates i Most extensive climate region on land ii Moisture demand POTET supply PRECIP There is always a deficit 11 9 15 11 11 15 11 13 15 and 11