the biosphere chapter 42. climate average weather condition in a region affected by: amount of...
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The BiosphereThe Biosphere
Chapter 42Chapter 42
ClimateClimate
Average weather condition in a region
Affected by:
amount of incoming solar radiation
prevailing winds
elevation
Average weather condition in a region
Affected by:
amount of incoming solar radiation
prevailing winds
elevation
The AtmosphereThe Atmosphere
Three layers
Outer mesosphere
Middle stratosphere (includes ozone layer)
Inner troposphere (where air is warmed by
the greenhouse effect)
Three layers
Outer mesosphere
Middle stratosphere (includes ozone layer)
Inner troposphere (where air is warmed by
the greenhouse effect)
Warming the AtmosphereWarming the Atmosphere
Solar energy warms the atmosphere and sets
global air circulation patterns in motion
Solar energy warms the atmosphere and sets
global air circulation patterns in motion
Rotation and Wind DirectionRotation and Wind Direction
Earth rotates faster under the air at the equator than it does at the poles
Deflection east and west
Earth rotates faster under the air at the equator than it does at the poles
Deflection east and west
Seasonal VariationSeasonal Variation
Northern end of Earth’s axis tilts toward
sun in June and away in December
Difference in tilt causes differences in
sunlight intensity and day length
The greater the distance from the equator,
the more pronounced the seasonal changes
Northern end of Earth’s axis tilts toward
sun in June and away in December
Difference in tilt causes differences in
sunlight intensity and day length
The greater the distance from the equator,
the more pronounced the seasonal changes
Varying TemperaturesVarying Temperaturescold
cool temperature
warm temperature
tropical(equator)tropical
warm temperature
cool temperature
cold March
December
September
June
231/2º
PollutantsPollutants
Substances with which an ecosystem
has had no prior evolutionary
experience
No adaptive mechanisms are in place
to deal with them
Substances with which an ecosystem
has had no prior evolutionary
experience
No adaptive mechanisms are in place
to deal with them
Ozone ThinningOzone Thinning
In early spring and summer ozone
layer over Antarctica thins
Seasonal loss of ozone is at highest
level ever recorded
In early spring and summer ozone
layer over Antarctica thins
Seasonal loss of ozone is at highest
level ever recorded
Effect of Ozone ThinningEffect of Ozone Thinning
Increased amount of UV radiation
reaches Earth’s surface
UV damages DNA and negatively
affects human health
UV also affects plants, lowers primary
productivity
Increased amount of UV radiation
reaches Earth’s surface
UV damages DNA and negatively
affects human health
UV also affects plants, lowers primary
productivity
Air PollutantsAir Pollutants
Carbon oxides
Sulfur oxides
Nitrogen oxides
Volatile organic compounds
Photochemical oxidants
Suspended particles
Carbon oxides
Sulfur oxides
Nitrogen oxides
Volatile organic compounds
Photochemical oxidants
Suspended particles
Protecting the Ozone LayerProtecting the Ozone Layer
CFC production has been halted in
developed countries, will be phased out in
developing countries
Methyl bromide will be phased out
Even with bans it will take more than 50
years for ozone levels to recover
CFC production has been halted in
developed countries, will be phased out in
developing countries
Methyl bromide will be phased out
Even with bans it will take more than 50
years for ozone levels to recover
Thermal InversionThermal Inversion
Weather pattern in which a layer of cool, dense air is trapped beneath a layer of warm air
Weather pattern in which a layer of cool, dense air is trapped beneath a layer of warm air
cool air
warm inversion air
cool air
normal circulationcool air
warm air
cooler air
Industrial SmogIndustrial Smog
Gray-air smog
Forms over cities that burn large amounts of
coal and heavy fuel oils; mainly in
developing countries
Main components are sulfur oxides and
suspended particles
Gray-air smog
Forms over cities that burn large amounts of
coal and heavy fuel oils; mainly in
developing countries
Main components are sulfur oxides and
suspended particles
Photochemical SmogPhotochemical Smog
Brown-air smog
Forms when sunlight interacts with
components from automobile exhaust
Nitrogen oxides are the main culprits
Hot days contribute to formation
Brown-air smog
Forms when sunlight interacts with
components from automobile exhaust
Nitrogen oxides are the main culprits
Hot days contribute to formation
Acid DepositionAcid Deposition
Caused by the release of
sulfur and nitrogen
oxides
Coal-burning power
plants and motor vehicles
are major sources
Caused by the release of
sulfur and nitrogen
oxides
Coal-burning power
plants and motor vehicles
are major sources
Suspended Particulate MatterSuspended Particulate Matter
Ocean CurrentsOcean Currents Upper waters move in currents that distribute nutrients
and affect regional climates
Upper waters move in currents that distribute nutrients
and affect regional climates
Rain ShadowRain Shadow
Air rises on the windward side, loses moisture
before passing over the mountain
Air rises on the windward side, loses moisture
before passing over the mountain
MonsoonsMonsoons
A pattern of wind circulation that changes
seasonally
Affect continents north and south of warm-
water oceans
Can cause seasonal variation in rains
A pattern of wind circulation that changes
seasonally
Affect continents north and south of warm-
water oceans
Can cause seasonal variation in rains
Coastal BreezesCoastal Breezes
Breeze blows in direction of warmer region Direction varies with time of day
Breeze blows in direction of warmer region Direction varies with time of day
Biogeographic RealmsBiogeographic Realms
Six areas in which plants and animals
are somewhat similar
Maintain their identity because of
climate and physical barriers that tend
to maintain isolation between species
Six areas in which plants and animals
are somewhat similar
Maintain their identity because of
climate and physical barriers that tend
to maintain isolation between species
BiomesBiomes
Regions of land characterized by habitat
conditions and community structure
Distinctive biomes prevail at certain
latitudes and elevations
Regions of land characterized by habitat
conditions and community structure
Distinctive biomes prevail at certain
latitudes and elevations
nearctic
neotropical
australian
oriental
palearctic
ethiopian
Hot SpotsHot Spots
Portions of biomes that show the greatest
biodiversity
Conservationists are working to inventory
and protect these regions
24 hot spots hold more than half of all
terrestrial species
Portions of biomes that show the greatest
biodiversity
Conservationists are working to inventory
and protect these regions
24 hot spots hold more than half of all
terrestrial species
DesertsDeserts
Less than 10 centimeters annual
rainfall, high level of evaporation
Tend to occur at 30 degrees north and
south and in rain shadows
One third of land surface is arid or
semiarid
Less than 10 centimeters annual
rainfall, high level of evaporation
Tend to occur at 30 degrees north and
south and in rain shadows
One third of land surface is arid or
semiarid
Dry Shrublands and WoodlandsDry Shrublands and Woodlands
Semiarid regions with cooler, wet
winters and hot, dry summers
Tend to occur in western or southern
coastal regions between latitudes of
30 and 40 degrees
Semiarid regions with cooler, wet
winters and hot, dry summers
Tend to occur in western or southern
coastal regions between latitudes of
30 and 40 degrees
Forest BiomesForest Biomes
Tall trees form a continuous canopy
Evergreen broadleaves in tropical latitudes
Deciduous broadleaves in most temperate
latitudes
Evergreen conifers at high temperate elevations
and at high latitudes
Tall trees form a continuous canopy
Evergreen broadleaves in tropical latitudes
Deciduous broadleaves in most temperate
latitudes
Evergreen conifers at high temperate elevations
and at high latitudes
Arctic TundraArctic Tundra
Occurs at high latitudes between
polar ice cap and boreal forests
Summers are short and snow-free
Permafrost lies beneath surface,
causes waterlogging in summer
Nutrient cycling is very slow
Occurs at high latitudes between
polar ice cap and boreal forests
Summers are short and snow-free
Permafrost lies beneath surface,
causes waterlogging in summer
Nutrient cycling is very slow
Alpine TundraAlpine Tundra
Occurs at high elevations throughout the world
No underlying permafrost
Plants are low, cushions or mats as in arctic
tundra
Occurs at high elevations throughout the world
No underlying permafrost
Plants are low, cushions or mats as in arctic
tundra
How much are you aware?How much are you aware?Is the native vegetation of the place where you live forest,
grassland, or dessert?
Can you describe the physical characteristics of three plant species that are native to your area?
What body of water serves as the source of your tap water?
How is your electricity generated?
Where does your garbage go?
Is the native vegetation of the place where you live forest, grassland, or dessert?
Can you describe the physical characteristics of three plant species that are native to your area?
What body of water serves as the source of your tap water?
How is your electricity generated?
Where does your garbage go?
Biomes - LandBiomes - Land
Primary vegetation types Four basic land biomes:
Forest Grassland Desert Tundra
Primary vegetation types Four basic land biomes:
Forest Grassland Desert Tundra
Biomes - LandBiomes - Land
Forest Tropical forests - Highly diverse and capture all light Temperate forests - Deciduous trees which drop leaves annually Boreal forests - highly uniform, coniferous trees of 1 or 2 species Chaparrel - woody spiny evergreen shrubs
Grassland - area where rainfall is not enough for tree growth Tropical - savannas - free trees - cleared by fires Temperate - prairies (tall grass) and steppes (short grass)
Forest Tropical forests - Highly diverse and capture all light Temperate forests - Deciduous trees which drop leaves annually Boreal forests - highly uniform, coniferous trees of 1 or 2 species Chaparrel - woody spiny evergreen shrubs
Grassland - area where rainfall is not enough for tree growth Tropical - savannas - free trees - cleared by fires Temperate - prairies (tall grass) and steppes (short grass)
Biomes - LandBiomes - Land
Desert Rainfall is sparse Animals and plants have evolved ways to conserve
water
Tundra Coldest biome - close to the poles Permafrost - keeps soils moist and bogged
Desert Rainfall is sparse Animals and plants have evolved ways to conserve
water
Tundra Coldest biome - close to the poles Permafrost - keeps soils moist and bogged
Biomes - AquaticBiomes - Aquatic
Freshwater Lakes and Ponds - surrounded by land
Vernal ponds - dry up in the summer
Rivers and Streams - flowing water Wetlands - support above water plants
Saltwater Oceans Coral reefs Estuaries
Freshwater Lakes and Ponds - surrounded by land
Vernal ponds - dry up in the summer
Rivers and Streams - flowing water Wetlands - support above water plants
Saltwater Oceans Coral reefs Estuaries
Soil Characteristics Soil Characteristics
Amount of humus
pH
Degree of aeration
Ability to hold or drain water
Mineral content
Amount of humus
pH
Degree of aeration
Ability to hold or drain water
Mineral content
Soil ProfilesSoil Profiles
Layer structure of
soil
Soil characteristics
determine what
plants will grow and
how well
Layer structure of
soil
Soil characteristics
determine what
plants will grow and
how well
Rain forest
Desert
Grassland
Deciduous Coniferous
LakesLakes
Bodies of standing freshwater
Eutrophic lake is shallow, nutrient-rich, has
high primary productivity
Oligotrophic lake is deep, nutrient-poor,
has low primary productivity
Bodies of standing freshwater
Eutrophic lake is shallow, nutrient-rich, has
high primary productivity
Oligotrophic lake is deep, nutrient-poor,
has low primary productivity
Lake ZonationLake Zonation
LITTORAL
limit of effective light penetration
LIMNETICLITTORAL
PROFUNDAL
Thermal LayeringThermal Layering
In temperate-zone lakes, water can form distinct layers during summer
In temperate-zone lakes, water can form distinct layers during summer
wind
THERMOCLINE
Seasonal OverturnSeasonal Overturn
In spring and autumn, temperatures in the
lake become more uniform
Oxygen-rich surface waters mix with
deeper oxygen-poor layers
Nutrients that accumulated at bottom are
brought to the surface
In spring and autumn, temperatures in the
lake become more uniform
Oxygen-rich surface waters mix with
deeper oxygen-poor layers
Nutrients that accumulated at bottom are
brought to the surface
EutrophicationEutrophication
How do nutrients enter a lake?
Can occur naturally over long time span
Can be triggered by pollutants
How do nutrients enter a lake?
Can occur naturally over long time span
Can be triggered by pollutants
StreamsStreams
Begin as springs or seeps
Carry nutrients downstream
Solute concentrations are influenced by
streambed composition and human
activities
Begin as springs or seeps
Carry nutrients downstream
Solute concentrations are influenced by
streambed composition and human
activities
EstuaryEstuary
Partially enclosed area where
saltwater and freshwater mix
Dominated by salt-tolerant plants
Examples are Chesapeake Bay, San
Francisco Bay, salt marshes of New
England
Partially enclosed area where
saltwater and freshwater mix
Dominated by salt-tolerant plants
Examples are Chesapeake Bay, San
Francisco Bay, salt marshes of New
England
Estuarine Food WebsEstuarine Food Webs
Primary producers are phytoplankton and
salt-tolerant plants
Much primary production enters detrital
food webs
Detritus feeds bacteria, nematodes, snails,
crabs, fish
Primary producers are phytoplankton and
salt-tolerant plants
Much primary production enters detrital
food webs
Detritus feeds bacteria, nematodes, snails,
crabs, fish
Mangrove WetlandsMangrove Wetlands
Tropical saltwater ecosystem
Form in nutrient-rich tidal flats
Dominant plants are salt-tolerant
mangroves
Florida, Southeast Asia
Tropical saltwater ecosystem
Form in nutrient-rich tidal flats
Dominant plants are salt-tolerant
mangroves
Florida, Southeast Asia
Rocky IntertidalRocky Intertidal
Grazing food webs prevail
Vertical zonation is readily apparent
Diversity is greatest in the lower littoral
zone
Grazing food webs prevail
Vertical zonation is readily apparent
Diversity is greatest in the lower littoral
zone
Sandy CoastlinesSandy Coastlines
Vertical zonation is less obvious than along
rocky shores
Detrital food webs predominate
Vertical zonation is less obvious than along
rocky shores
Detrital food webs predominate
Intertidal ZonesIntertidal Zones
Littoral zone is submerged only during
highest tides of the year
Midlittoral zone is regularly submerged and
exposed
Lower littoral is exposed only during
lowest tides of the year
Littoral zone is submerged only during
highest tides of the year
Midlittoral zone is regularly submerged and
exposed
Lower littoral is exposed only during
lowest tides of the year
Coral ReefsCoral Reefs
Develop in clear, warm waters near coasts or around volcanic islands, mainly between latitudes 25° north and south
Coral bleaching is on the rise – occurs when sea temperatures rise
Develop in clear, warm waters near coasts or around volcanic islands, mainly between latitudes 25° north and south
Coral bleaching is on the rise – occurs when sea temperatures rise
Ocean ProvincesOcean Provinces
Benthic province - sediments and
rocks at bottom
Pelagic province - full volume of water
Neritic zone is near continental shelves
Oceanic zone is ocean basins
Benthic province - sediments and
rocks at bottom
Pelagic province - full volume of water
Neritic zone is near continental shelves
Oceanic zone is ocean basins
The Open OceanThe Open Oceanoceanic
zone
BENTHIC PROVINCE
PELAGIC PROVINCE 0
200
1,000
2,000
4,000
11,0000 depth (meters)
air at surfacecontinental
shelf
bathyal zone
abyssal zone
hadal zone
deep-sea trenches
sunlit water
"twilight" watersunless
water
intertidal zone
neritic zone
PhytoplanktonPhytoplankton
Floating or weakly swimming
photoautotrophs; form the base for most
oceanic food webs
Ultraplankton are photosynthetic bacteria
Floating or weakly swimming
photoautotrophs; form the base for most
oceanic food webs
Ultraplankton are photosynthetic bacteria
Deep Ocean Food WebsDeep Ocean Food Webs
Regions too dark for photosynthesis Marine snow supports a detrital food web Organic matter drifts down from shallower
water Diverse species migrate up and down in
water column daily
Regions too dark for photosynthesis Marine snow supports a detrital food web Organic matter drifts down from shallower
water Diverse species migrate up and down in
water column daily
Hydrothermal VentsHydrothermal Vents
Openings in ocean floor that spew mineral-rich, superheated water
Primary producers are chemoautotrophic bacteria; use sulfides as energy source
Life may have originated in similar conditions on early Earth
Openings in ocean floor that spew mineral-rich, superheated water
Primary producers are chemoautotrophic bacteria; use sulfides as energy source
Life may have originated in similar conditions on early Earth
UpwellingUpwelling
Upward movement of water along a coast; replaces surface waters that move away from shore
Upward movement of water along a coast; replaces surface waters that move away from shore
ENSOENSO
El Nino Southern Oscillation
Climactic event that involves changes
in sea surface temperature and air
circulation patterns in the equatorial
Pacific Ocean
El Nino Southern Oscillation
Climactic event that involves changes
in sea surface temperature and air
circulation patterns in the equatorial
Pacific Ocean
Between ENSOsBetween ENSOs
Warm water and heavy rainfall move west
across the Pacific
Warm moist air rises in the western Pacific
causing storms
Upwelling of cool water along western
coasts
Warm water and heavy rainfall move west
across the Pacific
Warm moist air rises in the western Pacific
causing storms
Upwelling of cool water along western
coasts
Between an ENSOBetween an ENSOclear skies, dry descending air
masses, high pressure
equatorial trade winds blow east to west
warm, moist, ascending air masses, low pressure, storms in western Pacific
warming water
upwelling of cold water to 30-160 feet below surface
high winds blow west to east
During an ENSODuring an ENSO
Trade winds weaken and warm water flows east
across the Pacific
Sea surface temperatures rise
Upwelling along western coasts ceases
Heavy rainfall occurs along coasts, droughts
elsewhere
Trade winds weaken and warm water flows east
across the Pacific
Sea surface temperatures rise
Upwelling along western coasts ceases
Heavy rainfall occurs along coasts, droughts
elsewhere
During ENSOsDuring ENSOsclear skies, descending air masses, high pressure
high winds blow west
warm, moist ascending air masses, low
pressure, storms
rain falls in central Pacific
no upwelling; cold water as deep as 500 feet below surface
trade winds weaken; warm water flows east
Cholera ConnectionCholera Connection
Cholera outbreaks are correlated with rises
in sea temperature
Dormant stage of causative organism lives
in copepods
Copepod population increases when
phytoplankton increase in warming seas
Cholera outbreaks are correlated with rises
in sea temperature
Dormant stage of causative organism lives
in copepods
Copepod population increases when
phytoplankton increase in warming seas