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Anthropogenic Sources of Climate Change (Global Warming). Chapter 17 APES. Anthropogenic Sources of Climate Change. Two main causes 1. Deforestation 2. Increasing Greenhouse Gas levels Burning Fossil Fuels Main villain is currently CO2. Deforestation. Deforestation - US.

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Anthropogenic Sources of Climate Change (Global Warming)


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anthropogenic sources of climate change
Anthropogenic Sources of Climate Change
  • Two main causes

1. Deforestation

2. Increasing Greenhouse Gas levels

      • Burning Fossil Fuels
      • Main villain is currently CO2
deforestation us
Deforestation - US
  • About one half of the forests that covered the Earth are gone
  • Since 1600, 90% of the U.S. forests have been cleared away
results of deforestation
Results of Deforestation
  • Loss of trees’ ability to remove CO2
  • Decaying trees release CO2 and methane
    • 25% of global GHG emissions
  • Fallen trees are often burned which releases CO2
    • Accounts for 20% of global CO2 emissions
  • Deforestation the largest source of emissions in developing countries
greenhouse effect1
Greenhouse Effect
  • Certain gases in the Earth’s atmosphere trap energy from the sun
    • carbon dioxide – water vapor
    • methane – nitrous oxide
  • Without these gases, the Earth’s average temperature would be about 60ºF colder
  • These gases are Greenhouse Gases
evidence of global warming
Evidence of Global Warming
  • CO2 and Temperature
mauna loa study
Mauna Loa Study
  • Study air chemistry in remote location in Hawaii from 1950’s to present
  • Showed annual fluctuations in CO2 btwn winter & summer (why it looks like a zig-zag)
  • Also a steady CO2 increase from 315 ppm by volume in 1958 to 370 ppm in 1999.
  • This graph has been on almost every APES test!!!
five warmest years on record
Five Warmest Years on Record
  • 2005
  • 1998
  • 2002
  • 2003
  • 2004

Since 1980, the Earth has experienced 19 of its 20 hottest years on record

evidence
Evidence
  • CO2 and Temperature
  • Glaciers
glaciers
Glaciers
  • Have been shrinking throughout the 20th Century
  • Loss of glaciers in South America and Asia is particularly rapid and will threaten the water supplies of millions of people
  • http://www.cnn.com/2007/TECH/science/11/26/andes.water.ap/index.html
evidence1
Evidence
  • CO2 and Temperature
  • Glaciers
  • Polar Ice
    • Arctic
    • Antarctic
    • Greenland
arctic ice1
Perennial ice may be 10 or more feet thick

New ice is only one to seven feet thick

Since 1970  10% loss of ice cover per decade

Arctic Ice
nasa sees rapid changes in arctic sea ice
NASA Sees Rapid Changes in Arctic Sea Ice

NEWS RELEASE: September 13, 2006

  • From 1970 until 2000 there was a 10 percent decrease in Arctic perennial sea ice every decade
  • Between 2004 and 2005 the ice shrunk abruptly by 14 percent
permafrost1
Permafrost
  • Where soil over 1-meter down never thaws
  • About 10% of Earth’s surface has permafrost
  • Tundra and taiga are characterized by extreme cold
    • 24 hours of sun during the summer
    • Huge amount of vegetation grows
  • In the last 11,000 years, the permafrost has not thawed
    • None of the vegetation has decayed
    • Decay releases CO2 and methane
permafrost2
Permafrost
  • Alaska permafrost temperature has increased 0.5° to 1.5° C since 1980,
  • Serious effects include
    • sinking roads and buildings
    • eroding tundra riverbanks
    • changes in tundra vegetation
    • increased carbon dioxide and methane emissions from thawed peat.
permafrost3
Permafrost
  • Estimates of billions of tons of methane
    • Will double existing methane in atmosphere
  • Methane is 20 to 60 times as strong of a greenhouse gas as CO2
antartica
Antartica
  • Land mass covered by multiple glaciers
  • Glaciers average 8000 feet thick
  • Represents 10% of all landmass on Earth
moulins
Moulins
  • Rivers of water about 10 meters in diameter that flow through the glacier
  • Bring melted water below the glaciers
  • Can cause glaciers to slip off bedrock into ocean
antarctica melting
Antarctica Melting

If all of the ice in the glaciers of Antarctica melt the oceans will rise

200 feet

greenland ice melt
Greenland Ice Melt
  • Glaciers located on three islands
  • Greenland loses 20% more ice than it gains each year
  • If all of the ice melts – oceans will rise 23 feet
  • If moulins work like those in Antarctica…
  • http://www.cnn.com/SPECIALS/2007/planet.in.peril/greenland.html
evidence2
Evidence
  • CO2 and Temperature
  • Glaciers
  • Polar Ice
    • Arctic
    • Antarctic
    • Greenland
  • Weather Severity
droughts
Droughts
  • The 1999-2002 national drought was one of the three most extensive droughts in the last 40 years
  • In 2002, the Western United States experienced its second worst wildfire season in the last 50 years; more than 7 million acres burned
  • The period from April through June of 1998 was the driest three-month period in 104 years in Florida, Texas, and Louisiana
evidence3
Evidence
  • CO2 and Temperature
  • Glaciers
  • Polar Ice
    • Arctic
    • Antarctic
    • Greenland
  • Weather Severity
  • Biome Changes
oceans absorb co 2
Oceans absorb CO2
  • CO2 in water makes Carbonic Acid
  • Increased CO2 especially in cold water
  • As cold deep ocean currents (abyssal) resurface they release CO2
  • Greater acidity of oceans is bleaching coral
consequence
Consequence
  • Cold Europe
thermohaline circulation
Thermohaline Circulation
  • Half Century of measurements by Britain's National Oceanography Centre
    • Suggest a noticeable slowing (30%)
    • Due to Arctic and Greenland ice melting
    • Europe may be colder- “mini-ice age”
consequence1
Consequence
  • Cold Europe
  • Increased Smog
consequence2
Consequence
  • Cold Europe
  • Increased Smog
  • Spread of Tropical Diseases
slide59

Tree eating wood beetles will be able to eat for longer periods without colder weather to kill them off. Occurring in Alaska.

consequence3
Consequence
  • Cold Europe
  • Increased Smog
  • Spread of Tropical Diseases
  • Changes in Biodiversity
changes in biodiversity
Changes in Biodiversity

Biomes

Shift of Alpine biomes up mountains and further North/South

changes in biodiversity1
Changes in Biodiversity

Biomes

Shift of Alpine biomes up mountains and further North/South

Die-offs

Coral bleaching die-offs of up to 50% in the Indian Ocean

dire prediction for world s coral reefs
Dire prediction for world's coral reefs

POSTED: 1404 GMT (2204 HKT), October 25, 2006

CHARLOTTE AMALIE, U.S. Virgin Islands (AP)

Researchers fear more than half the world's coral reefs could die in less than 25 years and say global warming may at least be partly to blame.

Sea temperatures are rising, weakening the reefs' resistance to increased pollutants, such as runoff from construction sites and toxins from boat paints. The fragile reefs are hosts to countless marine plants and animals.

"Think of it as a high school chemistry class," said Billy Causey, the Caribbean and Gulf Mexico director of the National Oceanic and Atmospheric Administration.

"You mix some chemicals together and nothing happens. You crank up the Bunsen burner and all of a sudden things start bubbling around. That's what's happening. That global Bunsen burner is cranking up."

Causey was one of some 200 private and government researchers from the Caribbean, Florida and U.S. Pacific islands who gathered in St. Thomas for a meeting of the NOAA's U.S. Coral Reef Task Force.

Last year's coral loss in the Caribbean waters supports predictions that 60 percent of the world's coral could die within a quarter century, said Tyler Smith of the University of the Virgin Islands.

"Given current rates of degradation of reef habitats, this is a plausible prediction," Smith said.

More than 47 percent of the coral in underwater study sites covering 31 acres around the U.S. Virgin Islands died after sea temperatures exceeded the norm for three months in 2005, said Jeff Miller, a scientist with the Virgin Islands National Park.

The unusual warm water can stress coral, causing it to lose its pigment and making it more vulnerable to disease.

This year, Caribbean coral narrowly avoided another widespread episode of bleaching when sea temperatures briefly surpassed levels considered healthy for reefs.

Up to 30 percent of the world's coral reefs have died in the last 50 years, and another 30 percent are severely damaged, said Smith, who studies coral health in the U.S. Virgin Islands and collaborates with researchers globally.

"U.S. Virgin Islands coral today is likely at its lowest levels in recorded history," Smith said.

The researchers said global warming was a potential cause of the abnormally high sea temperatures but was not the only suspect in the reefs' demise.

What causes disease in coral can be hard to pinpoint and could be a combination of things. Other threats include silt runoff from construction sites, which prevents the coral from getting enough sunlight, and a record increase in fleshy, green algae, which competes with coral for sunlight.

"Climate change is an important factor that is influencing coral reefs worldwide," said Mark Eakin, director of NOAA's Coral Reef Watch. "It adds to the other problems that we are having."

changes in biodiversity2
Changes in Biodiversity

Biomes

Shift of Alpine biomes up mountains and further North/South

Die-offs

Coral bleaching die-offs of up to 50% in the Indian Ocean

Extinctions

Golden Toads, Harlequin Frogs, ...

slide66
Global Warming Already Causing Extinctions, Scientists SayHannah Hoag for National Geographic News November 28, 2006
  • In Costa Rica about two-thirds of the 110 known harlequin frog species are extinct
  • In Antarctica, the Adélie penguin on Litchfield Island has disappeared.
changes in biodiversity3
Changes in Biodiversity

Biomes

Shift of Alpine biomes up mountains and further North/South

Die-offs

Coral bleaching die-offs of up to 50% in the Indian Ocean

Extinctions

Golden Toads, Harlequin Frogs, ...

Life Cycles

Gothic marmots emerge from hibernation about a month earlier than 30 years ago

life cycle changes
Life Cycle Changes
  • Marmots in the area now emerge from hibernation about a month earlier than they did 30 years ago
  • During the same period, the average April low temperature in Crested Butte rose 5.9 degrees
changes in biodiversity4
Changes in Biodiversity

Biomes

Shift of Alpine biomes up mountains and further North/South

Die-offs

Coral bleaching die-offs of up to 50% in the Indian Ocean

Extinctions

Golden Toads, Harlequin Frogs, ...

Life Cycles

Gothic marmots emerge from hibernation about a month earlier than 30 years ago

The average weight of adult female polar bears has decreased by more than 20% over the last 25 years

Physiology

slide70
Polar bears depend on ice

Wait near seal holes to snag a seal

Less ice = larger holes = more seals escape = polar bears eat less = store less fat = no milk for babies or themselves.

Global Warming Already Causing Extinctions, Scientists SayHannah Hoag for National Geographic News November 28, 2006
changes in biodiversity5
Changes in Biodiversity

Biomes

Shift of Alpine biomes up mountains and further North/South

Die-offs

Coral bleaching die-offs of up to 50% in the Indian Ocean

Extinctions

Golden Toads, Harlequin Frogs, ...

Life Cycles

Gothic marmots emerge from hibernation about a month earlier than 30 years ago

The average weight of adult female polar bears has decreased by more than 20% over the last 25 years

Physiology

Multiple areas affected

Migration

migratory species as indicators
Migratory Species as Indicators
  • Effects of climate change on the behaviour on migratory species are becoming increasingly evident.
  • Although migration is itself a flexible reaction to ecological conditions, migratory species seem more vulnerable than most wildlife as they use multiple habitats and sites and a wide range of resources through their migratory cycle.
  • www.cms.int/news/current_news_page.htm
slide74

Alien species like the Pacific Oyster brought to Europe for commercial reasons used not to be able to survive outside artificial pens. As the North Sea has grown warmer, the Pacific oyster has been able to breed in the wild and is now displacing native oysters in the Wadden Sea.

Incidence of flooding and resultant sediment run-off in Queensland, Australia damaged seagrass pasture leading to reduced growth and breeding rates for Green turtles

Baffin Bay hosts the largest concentrations of wintering Narwhals Here the trend has been for increased ice coverage in winter. The Narwhals depend on cracks in the ice to breathe and there have been several occasions when they have become trapped in the ice. Their site fidelity and the decrease in open water make them susceptible to Climate Change.

Habitat Changes

consequence4
Consequence
  • Cold Europe
  • Increased Smog
  • Spread of Tropical Diseases
  • Changes in Biodiversity
  • Droughts and fires
consequence5
Consequence
  • Cold Europe
  • Increased Smog
  • Spread of Tropical Diseases
  • Changes in Biodiversity
  • Droughts and fires
  • Sea levels rise
positive feedback1
Positive Feedback
  • Oceans currents and CO2 levels
    • Cold deep resurface and emit CO2
    • Warmer oceans do not take up CO2 and actually emit more CO2.
  • Permafrost melting
    • CO2 and methane released by decomposition
  • Arctic ice melting
    • Less reflection of sunlight – water and land heat up
  • Desertification
    • Soil dries out and releases CO2
why do we need to reduce
Why do WE need to Reduce?
  • Global Warming is a fact
    • Natural
    • Man-made
    • Both????
  • China and India will soon surpass U.S.A. in Greenhouse gas emission
  • If we do nothing, they will continue to do nothing (The Economist 9/9/06)
what can we do
What can we do?
  • Build Green- alternate energy for homes, passive solar heating, etc.
  • Reduce use of electricity from fossil fuels
  • Hydrogen powered vehicles
  • Invest in green companies
  • Reduce meat consumption
cattle and methane
Cattle and Methane
  • Cattle and other ruminant animals
    • Methane is by-product of digestion
      • Organisms in their stomachs break down fiber in grasses and grains they eat
what can we do1
What can we do?
  • Build Green
  • Reduce use of electricity from fossil fuels
  • Hydrogen powered vehicles
  • Invest in green companies
  • Reduce meat consumption
  • Carbon sequestration
carbon sequestration http sequestration mit edu technology overview index html
Carbon Sequestrationhttp://sequestration.mit.edu/technology_overview/index.html
  • Two primary types of carbon sequestration.
  • Carbon dioxide capture and storage
    • carbon dioxide is captured at its source (e.g., power plants, industrial processes)
    • subsequently stored in non-atmospheric reservoirs (e.g., depleted oil and gas reservoirs, unmineable coal seams, deep saline formations, deep ocean).
  • Enhancing natural processes (e.g., forestation).
  • What about seeding the ocean with iron to promote algal growth which will then absorb CO2 from air? What are the pros and cons of this? Read articles on Bb to find out!
  • [Encyclopedia of Energy (2004)].
carbon sequestration http sequestration mit edu technology overview index html1
Carbon Sequestrationhttp://sequestration.mit.edu/technology_overview/index.html

The Sleipner project in Norway's North Sea is the world's first commercial carbon dioxide capture and storage project

Started in 1996, it sequesters about one million metric tons of carbon dioxide each year

http://www.statoil.com/STATOILCOM/SVG00990.NSF/web/sleipneren?opendocument

what can we do2
What can we do?
  • Build Green
  • Reduce use of electricity from fossil fuels
  • Hydrogen powered vehicles
  • Invest in green companies
  • Reduce meat consumption
  • Carbon sequestration
  • Encourage ratification of Kyoto Protocol
cutting emissions
Cutting Emissions
  • Earth Summit 1992- Rio de Janeiro
    • Return greenhouse gas concentrations to 1990 conditions by 2000
    • Only Fiji ratified this treaty
  • Kyoto Protocol 1997- Kyoto Japan
    • 160 countries finally agreed on a new treaty
    • Roll back CO2, methane, & nitrous oxide emissions by 5% below 1990 conditions by 2012
    • US lobbied to have emissions treated as commodities for trading, banking, and borrowing.
    • Developing countries were exempt from emission limits
    • US & Australia did not sign
  • Earth Summit 2002- Johannesburg
    • It covered everything from measures to cut poverty, improve sanitation, improve ecosystems, reduce pollution, and improve energy supply for poor people.
    • Boycotted by US Government
intergovernmental panel on climate change ipcc
Intergovernmental Panel on Climate Change (IPCC)
  • http://www.ipcc.ch/ipccreports/ar4-syr.htm
  • United Nations sponsored working group of 2400 scientists studied human caused sources of climate change.
  • Important conclusions:
    • World climate has changed significantly over the past century
    • The balance of evidence suggests a discernible human influence on global climate
    • Climate models suggest that if current trends continue, global mean surface air temp will increase btwn 1ºC and 4.5ºC by 2100
what do the skeptics say remember these are skeptics
What do the skeptics say?(remember… these are skeptics)
  • CO2 less potent than thought
  • Methane levels declining
  • Models should be predicting more warming should be occurring but its not
  • If temp increases, more clouds form, raise earth’s albedo, atmosphere should cool
  • Excess CO2 stimulates plant growth
  • We are lucky to have CO2 otherwise we would be on our way to new ice age.