Desertification : loss of productive potential due to human activity. Can happen in A climates as well as in arid climates

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1 W, S,, m, 60 m What do these all have in common? Small group question: What leaf shape/shedding habit do you expect to find in each of these and why? Tropical Monsoon (m) Found primarily along eastern coastlines Result of seasonal reversal of winds Onshore, bringing rain in summer Offshore, bringing drier conditions in winter No severe drought Long growing season (it s tropical) Forest not as tall or diverse as roadleaf deciduous trees lose leaves in dry season Desertification : loss of productive potential due to human activity an happen in climates as well as in arid climates = Tropical savanna Period of severe drought long dry season during winter low sun season High temps. = high P Located between and : dry period is so long that broadleaf deciduous trees cannot earn enough during wet season to pay for leaves. Needleleaf trees or small leaves are best. Trees are dormant in dry season. Grasses and shrubs dominate 1

2 aobab or Upside-Down Tree grows in rica and ustralia. The legend says that after it was planted by God it kept moving, so God replanted it upside down iomes: Plant formations associated with major climate types. Tropical rainforest Tropical savanna Desert Temperate grassland Temperate forest Mediterranean scrub oreal forest Tundra Ice Where is located? What causes it to be predictably wet and dry? Pressure belts follow direct vertical rays of sun. In July, when sun is north of quator, ITZ affects rain in summer. In January, when sun is south of quator, Subtropical High affects dry in winter. Where is located? What causes it to be predictably wet and dry? Pressure belts follow direct vertical rays of sun. In July, when sun is north of quator, STH affects dry in S. Hemis. winter. In January, when sun is south of quator, ITZ affects rain in S. Hemis. summer. 2

3 iome: iological community associated with major climate region. hanges in vegetation along precipitation gradient in D m Decreasing precipitation Decreasing precipitation Mangrove: tropical, low energy coastal, woody plants, tolerate saltwater Mangrove Global mangrove distribution nvironmental issues associated with climates Mangrove destruction for aquaculture/wood chips Rainforest clearing for agriculture / ranching Honduras Shrimp ponds, Indonesia 3

4 limate Parameters: and Tropical: never below 64 average Never freezes : Tundra Northern laska, anada, Russia, rctic Ocean shores : Frost Greenland and ntarctica, ice caps Notice difference in temperature scales Too cold for trees Polar: never above 50 average Tundra in orange Frost in white Polar limates: too cold for trees! : Tundra limate at least one month above freezing (but below 50ºF) permafrost frozen ground around rctic Ocean coastal location moderates temperature low vegetation shrubs and grasses fauna migrate in for summer some can freeze What happens when water changes state from liquid to solid? : Frost limate never thaws out water always locked up as ice ntarctica and Greenland ice caps World s coldest temperatures 89.2 ( F) - ntarctica too cold for any vegetation penguins, polar bears, etc. Tundra: Hrafntinnusker, Iceland 4

5 Frost climate: ntarctica iome: iological community associated with major climate region. D Decreasing precipitation and D: the inbetween climates. How are and D alike? D Decreasing precipitation haracteristics of both and D climates Great variability Week to week frontal passage Seasonal air mass dominance Zone of air mass contrasts Lack constant heat of tropics or constant cold of polar climates, & D

6 Worldwide Distribution of limates and D Mesothermal (Mild mid-latitude) climates: summer dominated but can freeze fa: Subtropical = Mobile, almost (but not) tropical moist all year (small f ) warmest of climates = a dominated by mt air mass warm with high humidity, long summer tropical storms in summer S U.S., S hina dominated by temperate deciduous forest southern pines southern deepwater swamps drier part is tall-grass prairie In fa, enough water for vines In fa, enough light gets to forest floor for growth Pines common on sandy soils of coastal plain 6

7 fa wetlands: Distribution of cypress in S U.S. Typical cypress trees in southern deepwater swamps High stress, needleleaf deciduous, knees aldcypress versus Spruce pine In coastal saltwater environments, trees cannot survive dual strees of salt and freezes. Marsh grasses and reeds dominate Needleleaf deciduous versus needleleaf evergreen fb: Marine West oast f = moist all year b = cooler than fa (shorter growing season) dominated by mp air masses and relatively warm ocean currents rainy, drizzly, highest annual % cloud cover Pacific northwest, western urope temperate marine conifer forest (temp. rain forest) large needleleaf evergreens large sized spruce & fir, redwoods (N. mer.) Marine West oast: Temperate rain forest 7

8 fa subtropical, mt airmass, eastern side of continent fb Marine West oast, mp airmass, western side of continent ig needleleaf evergreens roadleaf deciduous Pacific oast Redwoods a: Mediterranean s = summer dry drought during growing season fire common scrub, stunted woodlands, grass, bulbs most near water bodies that moderate temperatures around Mediterranean, southern alifornia influenced by subtropical high and polar front Where is located? What causes it to be predictably wet and dry? Pressure belts follow direct vertical rays of sun. In July, when sun is north of quator, Subtropical High affects dry in summer. In January, when sun is south of quator, Polar Front affects wet in winter. Where is located? What causes it to be predictably wet and dry? Pressure belts follow direct vertical rays of sun. In July (winter in S. Hemis.), when sun is north of quator, Polar Front affects wet in winter. In January (summer in S. Hemis), when sun is south of quator, Subtropical High affects dry in summer. Mediterranean s= summer dry 8

9 haparral, Mediterranean scrub-shrub (leathery leaves, coppice sprouting common) Fires in San ernadino, alifornia after dry summer, landslides occur during winter rains North merican Grasslands Drier parts of and D climates, transitional to climates. cotone Grasslands and large herbivores iome: iological community associated with major climate region. D fb fb fa drier Decreasing precipitation Decreasing precipitation 9