Global Climate Classification and Vegetation Relationships

Global Climate Global Climate Classification Classification

andand Vegetation Vegetation

RelationshipsRelationships

Weather vs. ClimateWeather vs. Climate• Weather

– short-term condition of the atmosphere

– days, weeks– meteorologists

• Climate– long-term (30 year) average of

weather conditions and extremes – climatologists

Climate DeterminantsClimate Determinants

• Insolation and Temperature– latitude, altitude, land-water,

ocean currents, mountain barriers

• Precipitation – Air pressure (ITCZ and

Subtropical Highs)– Air mass influences– Prevailing winds

The Köppen Climate Classification

• A Tropical (equatorial regions)

• B Deserts (arid, semiarid)

• C Mesothermal (mild winter)

• D Microthermal (boreal, cold winter))

• E Polar (always cold)

• H Highland (mountains, plateaus)

The Köppen Climate Classification

3 letter systemFirst letter = temperature

Second letter = precipitation

Third letter = finer shades of temp

Csb = mediterranean C = middle latitude temps

s = summer dry

b = warm summers (as opposed to hot [a])

Reading a Climograph

Climate Regions

Koppen’s Categories

Vegetation Regions

Tropical Climates (A)

Tropical Humid Climates (Af)• 1/3 of Earth’s total surface (about 20 ºN to 20 ºS)

• Consistently warm (all months > 18ºC/64.4 ºF)

• Annual precipitation exceeds evaporation

• Daily temp range exceeds annual temp range

• Subcategories based on rainfall (ITCZ influence)

– Tropical rainforest– Tropical monsoon– Tropical savanna

Tropical Rainforest (Af)• High rainfall all year (>2” /

month)• Straddles Equator by 5o - 10o

Tropical Rainforest– Vegetation : Highest biomass on earth! Highest

biodiversity on earth! Thousands of species, tall trees, many canopy layers, evergreen, broadleaf trees, epiphytes, lianas (vines), climbers, stranglers, ferns

– Fauna: More species than all other biomes combined!, colorful insects, amphibians, reptiles, and birds, few large animals, high density of biomass and incredible species diversity

• Other: Among most threatened biomes

Buttresses

Lianas

Epiphytes

Strangler Fig3-Toed Sloth, Panama

Deforestation, Malaysia

Savanna (Aw) – Tropical Grassland Climates

• Region/Distribution: Subequatorial Africa, and South America, Southern India (25° N and S Latitude)

• Vegetation: Continuous cover of grasses, scattered trees or shrubs

• Fauna: Large grazing animals; antelope, zebra, giraffe, elephant, Predators: lions, leopards, cheetahs, hyenas

• Other: Susceptible to desertification

Acacia and Wildebeest Serengeti Plain, Tanzania

Masai Reserve, Kenya

Dry / Semiarid Climates (B)• Occupy about 1/3 of Earth’s land area (Most extensive

climate over land surface)

• Evaporation exceeds precipitation (water deficit)

• Subcategories– Desert (BW)– Steppe (BS)

Dry Arid / Semiarid Climates (B)

Deserts (BW): dry

Deserts (BW):

Desert Causation: • High Pressure Cells and resultant stability• Rainshadows

Precipitation: • Scarce: <10 inches/year• Unreliable: wide variation from average• Intense: convective downpours

Temperature: • Widest range: up to 100oF/day!• Hot at low latitudes, wide variation at higher latitudes

Deserts• Vegetation: Widely scattered thorny bushes,

cacti, small flowers, extensive shallow roots or long tap roots, shrubs, succulents

• Fauna: Many rodents, lizards, toads, snakes and other reptiles, many birds, owls, vultures, many insects (adaptive strategies)

• Other: Deserts cover roughly 1/3 of earth. May be growing due to desertification.

• Steppe: semi-arid high elevation or high latitude

Desert Plant Survival Strategies schlerophyllous adaptations

- small, waxy leaves or thorns replace leaves

succulents - stems modified to spongy water storage structures

ephemerals (obligate seeders) - fast reproductive cycle

wide spacing with shallow roots - collect sparse rainfall

Animal survival strategies?

Death Valley, CA

Anza-Borrego State Park, CA Winter 2004/2005

Organ Pipe CactusOrgan Pipe National Monument, Arizona

Steppe (BS): temperate grasslands

• more precipitation than BW

• narrower temperature ranges

• grasslands

Grassland (temperate)

• Region/Distribution: Central North America, parts of Africa, Australia, SE South America (Pampas)

• Soil: very fertile soils, best on earth• Vegetation: Grass tall to short prairie, pampas,

steppe. Sod forming grasses, Sparse bushes, occasional trees in some areas

• Fauna: large grazing animals, bison, antelope, wild horses, kangaroos, giraffes, burrowing animals: rabbits, prairies dogs…; predators: coyotes, lions, leopards…...

• Other: Most N. American grasslands have been converted to agricultural fields. Wild grazers replaced by cattle, sheep, goats. Less than 1% of original grasses left.

Mesothermal Climates (C)• “Middle temperature”• True seasonality

(air mass conflict)• Subdivisions based on

precipitation variation– humid subtropical– marine west coast– Mediterranean

Subtropical Forest Sarasota, Florida

Marine West CoastTemperate Rainforest

Olympic Peninsula, Washington

Mesothermal Climates (C)

Humid SubtropicalMarine West Coast

Mediterranean

Humid SubtropicalMidlatitude Forests

• Hot summer, substantial year-round precipitation

• Low latitude east coasts (warm currents).

• Summer max precipitation. • Cold spells

Cfa - New Orleans, LA

Temperate Forest (Deciduous)• Region/Distribution: Western Europe, East

Asia, Eastern U.S.. Between 30-50° north or south

• Soil: brown soils, good for agriculture

• Vegetation: Broad-leafed deciduous trees, (120-150’ tall), oaks, hickories, maples,…

• Fauna: mammals such as white tail deer, porcupines, raccoons, rabbits, squirrels, most carnivores eliminated by hunting i.e. wolf, mountain lion, bobcat; many birds; frogs and salamanders, snakes

• Other: Biota well adapted to seasonality including hibernation, migration

Mediterranean• Dry summers (shifting subtropical

highs)• Surrounds Mediterranean• Also on west coasts near 30o N

and S (Australia, S. Africa, Chile)

Chapparal

Mediterranean • Region/Distribution: West coast and Central

California, SW. Australia, tip of S. Africa, West Peru. Chile, Mediterranean (good wine places!)

• Vegetation: Grassland, scattered trees (oaks, eucalyptus), scrub. Fire tolerant, sclerophyllous (hard leaf) evergreens, chaparral (scrubby evergreen)

• Fauna: Burrowers like ground squirrels, gophers; deer, mountain lions, coyotes, many birds

• Other: Susceptible to fire during dry season, some species need fire to regenerate, Susceptible to erosion and desertification, development, threatened biome

Manzanita

Microthermal Climates (D)

Virtually restricted to Northern Hemisphere.

Subarctic Climates (Boreal or Taiga)• 50o-70o N latitude

• long, bitterly cold winters

• highest annual temp range: up to 100O F

•Great annual temperature ranges (continentality, air mass conflicts)

Dw – Calgary, Canada

Coniferous (Boreal) Forest – Koppen D

• Region/Distribution: Northern parts of North America, Europe and Asia, South So. America, much of Russia

• Vegetation: Coniferous (mostly evergreen) forest, ex. Spruce, Fir, Pine, Larch, needle-leaved

• Fauna: Large herbivores: moose, elk; small herbivores: squirrels snowshoe hare, beaver; Predators: wolves, foxes, bears, lynx, weasel family; Mosquitoes in summer

• Other: Acid rain, logging , oil drilling, hunting of predators

Fir Trees, Alaska

British Columbia

Spruce Needles

Polar Climates (E)- all months < 50OF

Polar Climates (E)- all months < 50OF

• Tundra (ET)– warmest month 32-50F

• Ice caps (EF)– warmest month below 32F

• Both have very low precipitation

Tundra

Region/Distribution: North of the Boreal Forest, high latitudes of northern hemisphere in a belt around the Arctic Ocean, near the coast Soil: Permafrost, no true soil development Vegetation: Low growing lichens, mosses, grasses, sedges, dwarf shrubs, small plants typically ground hugging or warmth preserving in some wayFauna: Small burrowing mammals, lemmings, also foxes, lynx, owls, grizzly bear, caribou and musk ox: migrants Other: many insects in summer, standing water

Highland Climates (H)

How are these like the poles? How different?

Highland Climates (H)

How are these like the poles? How different?

• Lower temperatures

• More moisture available

• More insolation

• High winds in both

Where in the world is?…..

Verkhoyansk, Russia (67.4 N, 133.3 E)

Where in the world is?…..

Iquitos, Peru (3.4 S, 73.2 W)

Where in the world is?…..

Hilo, Hawaii

Where in the world is?…..

West Point, NY

Where in the world is?…..

San Francisco, California

The Köppen Climate Classification

• A Tropical (equatorial regions)

• B Deserts (arid, semiarid)

• C Mesothermal (mild winter)

• D Microthermal (boreal, cold winter)

• E Polar (always cold)

• H Highland (mountains, plateaus)

The Köppen Climate Classification

• A Tropical (equatorial regions)

• B Deserts (arid, semiarid)

• C Mesothermal (mild winter)

• D Microthermal (boreal, cold winter)

• E Polar (always cold)

• H Highland (mountains, plateaus)

Riparian Vegetation

Vegetation that grows along water courses.

Often supports richer diversity of plant and animal life, including more hardwood trees in a dry environment.

Vertical Zonation of Vegetation

Vegetation Succession

Pioneer Stage Climax Stage

Occurs after disturbances: fires, storms, landslides, etc.

Ecological InvasionsCalifornia Invasive Species: Old World Grape, livestock, Eucalyptus (Gum Trees), wild hog, mustards, horse, Mediterranean grasses/mustards

Methods of Transfer• Domesticated animals (fur, droppings)• Ornamentals• International tourism/migrations (New Zealand)

Problems with Invasives• Often out-compete endemics.• Don’t provide habitat for local fauna.• Upset balance of ecosystem.

The American Chestnut100 feet tall, thick symmetrical branches, over an acre of greenery, about a million lush leaves in all. Massive quantities of protein-rich nuts.

In 1904 a handful of Asian chestnut trees were planted in New York City at the Bronx Zoo. An Asian chestnut blight quickly destroyed over 99.99 percent of the American Chestnut population - almost all of four billion trees - annihilating at least six specialized insect species, decimating wild turkey populations, and depriving humans of a priceless resource in a single generation.

This loss represented one fourth of the tree cover in the Appalachians!