Transcript Global Climates and Biomes

Global Climates and Biomes
Weather v. Climate
• Weather
a. short-term conditions
b. temperature, humidity, precipitation
• Climate
a. average weather that occurs in a certain region
over a period of time
b. based on temperature and precipitation
Earth’s Atmosphere
• Five layers of gases
a. troposphere
- N, O, and H2O vapor
- location of weather
b. stratosphere
- ozone (O3) layer
- absorbs the sun’s UV-B and UV-C radiation
c. mesosphere
d. thermosphere
- blocks harmful x-ray and UV-radiation
- Northern Lights
e. exosphere
Unequal Heating of Earth
• 3 causes
a. variation in angle of Sun ray’s striking Earth
b. variation in surface area from sun’s rays
distribution
c. albedo: reflection of sunlight from Earth’s
surface
- higher the albedo, the more solar energy
is reflected and less that is absorbed
http://bcs.whfreeman.com/friedlandapes/#668210__690859__
Atmospheric Convection Currents
• Air has 4 properties
a. density
b. water vapor capacity
c. adiabatic heating or cooling
d. latent heat release
• Density
a. determines air movement
b. dense air sinks
• Water Vapor Capacity
a. saturation point
- temperature of air decreases, vapor
condenses, clouds form, precipitation occurs
• Adiabatic Cooling and Heating
a. response to change in pressure
b. cooling
- lower pressure of rising air allows air to
expand resulting in lower temperature
c. heating
- air sinks, pressure increases decreasing in
volume, and temperatures increase
• Latent heat release
a. energy is released when water vapor
condenses into liquid water
Convection Currents
• Global patterns of air movement initiated by
unequal heating of Earth
• Hadley Cells
a. air sinks at 30 degrees N and S
• Polar Cells
a. air sinks at 90 degrees N and S
Coriolis Effect
• Key component: Earth’s rotation
a. faster rotation speed at equator
- deflection of objects moving directly
north and south
ex) Earth rotates east, object goes west
b. easterlies and westerlies
http://bcs.whfreeman.com/friedlandapes/#668210__690859__
Earth’s Tilt and Seasons
• Causes different parts of the Earth to
experience different temperature and
precipitation
• Titled axis: 23.5
Ocean Currents
• Driven by temperature, gravity, winds, Coriolis
Effect and location of continents
• Currents
a. redistribute heat from the sun
b. influence climate and vegetation
• Gyres
a. patterns of water circulation
b. northern hemisphere: counterclockwise
southern hemisphere: clockwise
Upwelling
• Bring plant nutrients from the deeper parts of
the ocean to the surface
• Support large populations of phytoplankton,
zooplankton, fish, fish-eating seabirds
El Nino-Southern Oscillation
• Approx. every 3-7 years
• Steps
a. trade winds near S. America weaken
b. allows warm equatorial water to move
eastward toward the west coast of S. America
c. suppresses upwelling off coast of Peru
(decreases productivity)
Rain Shadow
• Windward side of mountain
a. air rises, expands, cools, condenses,
precipitates
• Other side of mountain (rain shadow)
a. air sinks, temps rise, dry weather
http://en.wikipedia.org/wiki/Rain_shadow
Biomes
• Combination of temperature and precipitation
• Contains distinct plant growth based on
climate
• Climate determines animal species
• Climate diagrams
• Climate Diagrams
a. growing season
b. relationship between temperature and
plant growth
http://mytriptothetundra.blogspot.com
http://www.heritagechristian.ca/science/science7/climatograms.html
Terrestrial Biomes
• Three categories
a. tundra and boreal forest
b. temperate
c. tropical
* Within these, there are 9 biomes
• Tundra
a. cold and treeless with low-growing vegetation
b. artic tundra, alpine tundra, antartic tundra
c. short growing season
d. permafrost – impermeable frozen soil layer
e. slow decomposition
http://www.marietta.edu/~biol/biomes/tundra.htm
• Boreal Forest
a. “Taiga”
b. coniferous (cone-bearing) evergreen trees
c. cold winters, short growing seasons
d. slow decomposition
http://www.marietta.edu/~biol/biomes/boreal.htm
• Temperate Rainforest
a. coastal biome
b. 12-month growing season
c. very large trees
d. slow decomposition due to cool temps
http://www.marietta.edu/~biol/biomes/temprain.htm
• Temperate seasonal forest
a. “deciduous forest”
b. broadleaf deciduous trees
c. four distinct seasons
d. rapid decomposition
e. greater productivity
f. one of first biomes converted to agriculture
http://www.marietta.edu/~biol/biomes/tempded.htm
• Woodland/Shrubland
a. “chaparral” – southern California
b. hot dry summers, mild rainy winters
c. 12-month growing season
d. plant growth constrained by low
precipitation in summer and low
temperatures in winter
e. poor nutrient soil
http://apenvkretzer.wikispaces.com/Period+7
• Temperate Grassland/Cold Desert
a. lowest average annual precipitation
b. cold harsh winters, hot dry summers
c. fires
d. “cold desert” – rain shadow of Rocky Mtns
e. nutrient rich soil
http://www.marietta.edu/~biol/biomes/desert.htm
• Tropical Rainforest
a. warm and wet
b. little seasonal variation
c. high productivity
d. rapid decomposition
e. more biodiversity per hectare than any
other terrestrial biome
http://www.marietta.edu/~biol/biomes/troprain.htm
• Tropical Seasonal Forest/Savanna
a. warm temperatures
b. distinct wet and dry seasons
c. savannas: open landscapes dominated by
grasses and scattered deciduous trees
d. fertile soil = agriculture and grazing
http://www.marietta.edu/~biol/biomes/tropdry.htm
• Subtropical Desert
a. 30 degrees N and S
b. extremely dry
c. sparse vegetation
d. “hot deserts”
http://www.marietta.edu/~biol/biomes/desert.htm
Aquatic Biomes
• Characterized by
a. salinity
b. depth
c. water flow
• Two Categories
a. freshwater and saltwater (marine)
• Streams and Rivers
a. flowing fresh water
b. streams: narrow, small amounts of water
rivers: wide, large amounts of water
c. inputs of organic matter
http://www.johnharveyphoto.com/cgibin/search.pl?Advanced=2&SearchIncludesphotos=set&metaEnum
Tag16=set&MetaTag16=160
http://savannahnow.com/news/2009-10-22/savannah-river-fourth-most-polluted-nation
• Lakes and Ponds
a. standing water
b. distinct zones
- littoral zone
- limnetic zone
- profundal zone
- benthic zone
http://www.ncparks.gov/Visit/parks/lano/main.php
http://www.fcps.edu/islandcreekes/ecology/pond.htm
• Freshwater Wetlands
a. submerged by water for part of the year
b. shallow enough to support vegetation
c. swamps, marshes, and bogs
d. highly productive providing ecosystem
services
http://medent.usyd.edu.au/arbovirus/mosquit/freshwet.htm
• Salt Marshes
a. along the coast (temperate)
b. found in estuaries
c. contain nonwoody emergent vegetation
• Swamps
a. along tropical and subtropical coasts
b. mangrove trees (salt tolerant)
- help protect coastlines from erosion and
storm damage
http://inchinapinch.com/hab_pgs/marine/mangrove/mangrove.htm
• Coral Reefs
a. found in warm, shallow water
b. most diverse marine biome
c. lives in water that’s poor in nutrients
d. relationship with photosynthetic algae
e. coral bleaching
http://travel.nationalgeographic.com/travel/world-heritage/great-barrier-reef/
http://ocean.nationalgeographic.com/ocean/photos/ocean-corals/
• Open Ocean
a. distinct zones
- photic
* photosynthesis
- aphotic
* lacks sunlight for photosynthesis
* chemosynthesis
- benthic
* ocean floor
http://cnx.org/content/m45562/latest
/
Terrestrial v. Aquatic Biomes
Terrestrial
Temperature and
precipitation affect the
rate of decomposition and
productivity of soil
Aquatic
Differences in water flow,
salinity and depth explain
why different species of
producers and consumers
live in different regions