California Overview Overview
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5/7/2012 CALIFORNIA Regional Landscapes of the Widely diverse United States and Canada region both physically and CALIFORNIA culturally. Prof. Anthony Grande Yet has a national ©AFG 2012 and world image as a single-place region. 2 OVERVIEW OVERVIEW • North-south alignment of physical features. •Most agriculturally-productive area of the U.S. • Subtropical climates dominant except for the in both variety and value. southeast desert and the higher mountain elevations. • An area shaped by the automobile. • Has a water deficiency. • Has the highest urbanization rate in U.S. • Is prone to earthquakes. • U.S./world perceptions of California vary. • Southern California is also subject to fires, – Region of the ideal American lifestyle. (Good) mudslides and temperature inversions. - modern, outdoor-oriented • Home to 37.7 million people = 12% of US pop. - “New Americana” the central element in the American cultural fabric. th • Economic powerhouse (world’s 8 largest economy, – Region of environmental and social problems. (Bad) ranking between Great Britain and Brazil in 2011.) 3 4 Advantages and Disadvantages Advantages and Disadvantages Today’s Advantages Today’s Disadvantages – Good climate. – Peripheral location (far from East Coast national – Abundant natural resources. core). – Strategic location on Pacific Rim (for trade with – Elongated state (limits interaction within it). Asia). – Automobile culture and urban sprawl. – Excellent natural harbor at San Francisco; – Land use competition. manmade harbors at Los Angeles, San Diego. – Need to move water to cities and farms. – Dominant political/economic force in America. – Taxation, zoning, regulations are a hindrance. – Vies for position as a national core. – Earthquakes, mudslides and fires are a threat. – Home to high-tech industries. – Ethnic diversity leads to clashes of cultures. – Ethnic diversity. 5 6 1 5/7/2012 Political Geography Question PHYSIOGRAPHY Cascade Mts. • Should California be separated into 3 states? Klamath Mts. – Northern, Central and Southern California Central Valley Lake Tahoe • Each area is unique both physically and culturally. San Francisco Sierra Nevada Bay • Each has its own priorities and outlooks. Owens Valley Coast Ranges • Each complains of having to “support” the Death Valley others. Salton Sea • (Similar arguments to the Quebec Secession or Los Angeles Basin Depression Upstate NY vs. Downstate NY or NYS vs. NYC) Channel Islands Colorado R 7 Valley 8 Geologic Formations Diagram of Block Mountains applied to California and Nevada A. Klamath Mts.: fault block B. Coast Ranges: folded ridge A C and valley structures B C. Cascade Mts.: volcanic D. Sierra Nevada: fault block D G F E. Basin and Range Area: fault block F. Central Valley: alluvial lowland B (former inland sea filled with sediment) E G. San Francisco Bay: an estuary of the Pacific Ocean (a separate geologic feature from the Central Valley) Central Sierra Owens Valley; Death Basins and ranges Valley Nevada Valley; Salton Basin 9 C A L I F O R N I A NEVADA 10 Physical Geography: Coast Ranges Topography rise out of the sea A. Klamath Mountains Area of rugged fault block metamor- phic mountains rising to 4,000 ft. B. Coast Ranges • Long, linear mountain ranges (3,000-5,000 ft high) paralleling the coast. The only gap is the Golden Gate and San Francisco Bay. • Heavily folded and faulted as a result of pressure from tectonic plate contact (North American Plate pushing against the Pacific Plate). • Effectively limits the marine influence to coastal areas. Big Sur 11 12 2 5/7/2012 The Golden Gate Redwoods National Park Coastal Giant Redwood trees are found on the windward (wet) side the COAST RANGE Coast Range. PACIFIC OCEAN SAN FRANCISCO BAY 13 14 Topography (continued) Cascades C. Cascades View of 1915 eruption from Lassen Peak, 10,462 ft. in Sacramento, CA. – Volcanic mountains Mt. Shasta 14,162 ft high) Lassen Volcanic Nat’l Park. created by the sub- Last erupted in 1915. duction of the Juan de Fuca Plate under the North America Plate. – Southern portion is in N. California – Lassen Peak and Mt. Shasta are dormant volcanoes. 15 16 Topography (continued) Donner Pass D. Sierra Nevada Donner Pass is the chief route – Between the Central Valley and Mt. Whitney across the Sierra Nevada con- the Basin and Range necting the Humboldt Valley – Fault-block mountains rising in Nevada with California’s to 14,505 ft at Mt. Whitney, the Central Valley. highest point in lower 48 states. – MjMajor barr ier to movement o f people and air masses. – Few mountain passes cross it. East face of the Sierra Nevada Infamous for the 1846 tragedy when the Donner Party Wagon Train, following the Owens Valley (in the rain shadow) California Trail across the Sierra Nevada, got caught in a blizzard and people resort- Basin and Range Province ed to cannibalism in order to survive. 17 18 3 5/7/2012 South Lake Sierra Topography (cont’d) Nevada Yosemite E. Basin and Range Area National – Area of Southern California, Park east the Coast Range and south of the Sierra Nevada. – Alterna ting ridges and bibasins. – Site of Owens Valley, Death Valley and the Salton Sea. – Colorado River Valley forms eastern boundary. – Topography creates a desert environment (rain shadow). 19 20 Giant Sequoia Tree Central Valley: Topography (cont’d) San Joaquin Valley Area F. Central Valley – 400 mi long and 90 mi wide – Former inland sea filled with sediment from rivers eroding the Sierra Neva da. – Divided into 2 segments: Sacramento Valley (north) and San Joaquin Valley (south). – Productive agricultural region • Extremely flat, fertile • Favorable climate (hot, sunny and dry; irrigation needed) 21 22 Climates of Topography (cont’d) California G. San Francisco Bay A variety of climates: – Tidal estuary of the Pacific Arid (BW and BS): desert and Ocean reached via a gap in semi-arid the Coast Range: Golden Highland (H): mountains Gate 2 1 Mediterranean (Csa): htdhot dry – Divided into four bays. summers and cool wet winters. – Fed by Sacramento and 3 Marine West Coast (Csb): San Joaquin rivers. Golden Gate cool summers; wetter than Csa. – Six major fault zones pass Found along the coast. through it, giving it its NW-SE 4 Conditions change rapidly alignment, and subjecting it to as you move away from the earthquakes. coast or up the side of a 23 mountain. 24 4 5/7/2012 Climate Creation Precipitation • Chief source of weather systems and • Precipitation varies moisture is the Pacific Ocean (westerly winds). with elevation and distance from the • A high-pressure cell moves north and south coast. alonggg the coast with the seasons, blocking • Coast Ranges and westward moving weather systems. • SFSan Franc isco ’s Sierra Nevada form fog and San –Moves north in summer; south in winter. rain shadow areas. Diego’s offshore –Its winter position allows Pacific moisture to reach • Cold ocean currents fog banks are the land. (Area is summer dry, winter wet.) create clouds, fog caused by warm • Temperature and position of cold offshore and rain offshore air passing over and along the coast. ocean current affects precipitation patterns. cold water. 25 26 San Francisco Fog Los Angeles Smog Smog (smoke + fog) is a type of air pollution created when by- products of combustion mix with atmospheric moisture. (Origgyinally caused by the mixing of soot with fog in coal burning areas.) Los Angeles smog is caused when vehicle emissions re- act with sunlight to form In the Los Angeles Basin the Fog is a cloud at ground level. photochemical pollution. problem is heightened by a com- bination of local weather and When warm, humid air passes over a colder land This mix of gases includes topography that act to prevent mass or body of water condensation occurs. particulates and ozone. dispersion of contaminants. A cloud forms near the surface. 27 28 Inversion Layer Santa Ana Winds Warm Mojave Desert Air 2 LA Basin Sierra 3 Nevada 1 Cool Pacific Ocean wind 1. Weak ocean winds push polluted air against the mountain. 2. However, the winds cannot break through stronger desert air layer. 3. They are forced to double back over the LA Basin, warming as they descend, and trapping pollution. 29 30 5 5/7/2012 Santa Ana Earthquakes Winds and Fire California exists on Low humidity, hot temperature plus wind creates a severe fire hazard. the eastern margin of the Pacific “Ring of Fire”, a geologic zone of earthquakes and volcanic activity. Dots show epicenters of major quakes. 31 32 The San Andreas Fault Earthquakes Major zones (common throughout California) – A. Southern California (LA southeast to the Imperial Valley) – B. San Francisco Bay Area Devastating earthquakes – 64 majjqor earthquakes since the first documented one in 1769 that killed people in a mission church. B – Thousands of little ones. – Awaiting the “Big One.” Earthquake Laws: world-leading A Sections of the fault are “locked” – Where to build, type of construct- (have not moved in hundreds of years) and ion, usage; have changed over are closely monitored by geologists. 33 time with new technologies. 34 San Francisco San Francisco Earthquake of 1906 Earthquake of 1989 35 36 6 5/7/2012 Mudflows and Landslides Mudflows Mudflows occur towards the end of the winter rainy season As saturated soil (up to 30% water by volume) loses inertia and usually in areas that on a slope, it can no long- experienced brush fires at the er support weight and end of the previous dry moves (flows) downhill. summer season. The steeper the slope, the faster it moves. Landslides usually occur during and after an earthquake. 37 38 Coastal Erosion DATES TO REMEMBER • MAY 7: Last day to hand in OPTIONAL EXTRA CREDIT PROJECTS listed on syllabus. – Short research paper on a preapproved topic – “Geography of the US & Canada in the News” • May 14: Last day to hand in REQUIRED LANDSCAPE EXERCISE Occurs during winter storms as waves batter – Last class lecture.