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Lake Tanganyika

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Also known as 'The Fossil Water Lake' because most of ... In Florida, the number of Loggerhead Sea Turtle nests counted on 13 miles of ... Loggerhead Continued ... – PowerPoint PPT presentation

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Title: Lake Tanganyika


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(No Transcript)
2
Lake Tanganyika
3

LOCATION...
This is a NASA satellite image showing Lake
Tanganyika, East Africa
4
Facts about Lake Tanganyika
  • Also known as The Fossil Water Lake because
    most of the lake's water is 'dead' or fossil
    water that may be an estimated 20 million years
    old.
  • It is the second largest of African lakes
    (containing 18 of planets liquid fresh water)
  • Famous for its extraordinary north (Burundi) to
    south (Zambia) extension of 670 km, and width of
    50 km.
  • Its mean depth is 570 m. maximum depth of
    1,470 m.
  • Bordering countries include Burundi, Tanzania,
    Zambia, Zimbabwe and the Democratic Republic of
    Congo.

5
Facts continued
  • The fisheries of Lake Tanganyika currently yield
    approximately 200,000 tons of fish per year
    (equivalent value of tens of millions of US
    dollars).
  • The lake contains 350 species of fish with new
    species being discovered regularly.
  • Even though only a few species of fish are eaten
    by people, its the most important source of
    animal protein for human consumption in this
    region of Central Africa.
  • Currently there are around 45,000 people directly
    involved in the fisheries operating from almost
    800 sites, there around 1 million people
    dependent on the fishers.
  • Region depends heavily on fisheries for their
    economy.

6
Climatic warming effects...
  • Researchers have found several lines of evidence
    showing that the increasing air and water
    temperatures are shrinking fish and algae
    productions.
  • Air temperatures over the lake have increased by
    about 1.5 degree Celsius, while wind speeds have
    diminished.
  • Without any circulation of water there can be no
    re-supply of nutrients from the deep water to the
    surface waters of the lake where the algae grows.
  • Algae forms the base of Lake Tanganyikas food
    chain, which ultimately feeds the commercially
    important fish.
  • Algae abundance has declined 20 percent.

7
Effects Continued
  • In addition to warming in lake water temperatures
    and decreased windiness researchers have analyzed
    organic matter from well-dated lake sediment
    cores and found clues that life in the ecosystem
    has been on a decline.
  • Climate change is harming the lakes ecosystem,
    overall reducing the fish populations by 1/3 over
    the past several years. The scientists found out
    that the harvest of sardines, the lake's main
    commercial fish, has declined by as much as 50
    since the 1970s.

Mulicorer used in study
8
Resulting Problems..
  • Decline in fish populations is causing several
    problems
  • Leads to serious consequences for the regions
    food supply
  • Serious problems of malnutrition in the area
    threatening the diets of several poor nations.
  • Severe implications for the economy of the
    regions people who depend heavily on the lake as
    a natural resource.

9
Global Warmings Effects on Biological Clocks
  • The timing of seasonal events in the life cycles
    of both plants and animals is shifting
    dramatically
  • 2004 report from the Pew Center for Global
    Climate Change summarized over 3 dozen reports
    linking global warming to ecological changes in
    the U.S. alone
  • The shifts are consistent across species,
    ecosystems, and geographic regions throughout the
    U. S.

10
Why should we worry?
  • Any given species will respond to changing
    climate in its own unique way
  • When this happens important links between
    interdependent species can be broken
  • The Wildlife Society published a recent report
    warning of the potential upheaval of natural
    communities and the possible disappearance of
    wildlife habitats

11
Great Tits
  • In the Netherlands springtime temperatures have
    increased 3.6 degrees F over the past 20 years
  • The tits are still laying eggs at the same time,
    but winter moths whose caterpillars are the
    primary food source for the fledglings are
    reaching their peak abundance 2 weeks earlier
    than they did 20 years ago

12
The Problem
  • The caterpillars themselves have also been
    starving lately by hatching before leaf buds on
    the surrounding oaks open. These leaves are
    there primary food source.
  • These are 2 examples of interdependent links
    being broken, both resulting in a species being
    separated from its primary food source

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14
Loggerhead Sea Turtle
  • In Florida, the number of Loggerhead Sea Turtle
    nests counted on 13 miles of beach declined from
    a record high of 17,629 to a record low of 7,599
    over the past 7 years

15
Loggerhead Continued
  • 44 percent of the 7,599 nests were wiped out by
    hurricanes before the eggs could hatch
  • Stronger hurricanes, higher sea levels and an
    increase in wildlife disease are all consequences
    of global warming

16
More Animals that are being Threatened
  • Black Guillemots in Alaska are losing their
    primary prey (Arctic Cod) as sea ice recedes
  • Sockeye Salmon have lost tens of thousands from
    their populations in British Columbia due to
    higher water temperatures and drought
  • Intertidal organisms in California have been
    moving northward as sea and air temperatures rise

17
More Consequences
  • The Mexican Jays in Arizona advanced their
    breeding season 10 days over 27 years in which
    the temperature rose 4.5 degrees F
  • American Robins in Colorado are breeding 2 weeks
    earlier than they did 30 years ago
  • Other threatened species include American
    Pikes, Polar Bears, Red-Winged Blackbirds,
    American Lobsters, Prothonotary Warblers, and
    American Alligators

18
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First Species Extinction Due to Global Warming
  • The Golden Toads which are known only to inhabit
    Costa Ricas Monteverde Cloud Forest have
    disappeared.
  • Amphibians are especially succeptible to climate
    changes

20
Conclusion
  • After observing growing trends, it is logical to
    say that the world and our environment is
    changing too fast today for evolution to keep up
    and the effects have disastrous potential.

21
Climate Change Impacts in the Eastern Carribean
  • Carribean Countries are extremely vulnerable to
    climate change.

22
Causes of Vulnerability
  • Physically small in size
  • Prone to natural disasters
  • Limited natural resources
  • High population growth rates
  • Surrounded by water
  • Poorly developed infrastructure
  • Economies sensitive to external shocks

23
Climate Change Variations
  • Sea level rise of 2 mm/year
  • Temperature percipitation
  • -change in weather patterns
  • (Precipitation)
  • -causes extreme events
  • -hurricanes

24
Natural Disasters
  • (floods, drought, landslides, hurricanes)s
  • - Hurricane Ivan
  • (2004)
  • -Hurricane Jeannie
  • (2004)

25
Hurricanes
  • Hurricane Ivan (2004)
  • -loss of life
  • -90 destruction of buildings
  • -loss of tourism plant
  • -devastation of nutmeg industry
  • Hurricane Jeannie (2004)
  • -1700 dead in Haiti
  • -destruction of property
  • -livelihoods

26
Resources at Risk
  • Coastal infrastructure
  • Human settlements
  • -Up to 90 settlement
  • Utilities
  • Roads

27
Resources at Risk
  • Coastal Ecosystems
  • -mangroves
  • -sea grass bed
  • -coral reefs
  • Socioeconomic areas
  • -tourism
  • -major employer
  • -50 GDP Bahamas
  • -47 GDP Barbados
  • -agriculture
  • -changing weather affects crop cycles
  • -Salt water intrusion is affecting rice
  • industry
  • -health
  • -heat stress disease
  • -water

28
Consequences of Sea Level Rising
  • Beach erosion
  • Destruction of freshwater habitats
  • Increase of storms
  • Degradation of mangroves, sea grass bed, coral
    reef

29
Tree Swallows
  • Climate change is affecting the breeding pattern
    of these birds
  • As springs are becoming warmer, tree swallows are
    breeding on average about 9 days earlier now than
    they did 30 years ago.
  • Studies in Britain show that in some cases these
    birds are nesting as much as 18 days earlier than
    30 to 40 years ago.

30
Tree Swallows Contd
  • Birds use temperature as a sign to start nesting
    partly because its a good predictor of the
    timing of food supplies for their young.
  • If the emergence of insects doesnt respond to
    the same temperature cues as birds do, nesting
    may become mis-timed in relation to their food
    supply.
  • As a result, they will breed less successfully
    until they can make the appropriate evolutionary
    adjustment to their timing of breeding.

31
Polar Bears
  • As temperatures rise, ice in arctic regions is
    freezing later and melting sooner than it once
    did.
  • As as result, polar bears spend less time
    accumulating fat reserves each winter and more
    time living off those reserves each summer.
  • Polar bears in the Western Hudson Bay have lost
    10 of their body weight and given birth to 10
    fewer cubs.

32
Arctic Fox
  • Arctic Foxes are specially adapted to thrive in
    cold winters and thick snows of the far north.
  • Where conditions are less extreme, the Arctic Fox
    is generally out-competed by its cousin, the more
    adaptable Red Fox.
  • As temperatures are increasing, the snow-line
    continues to recede further and further north.
  • As a result, the range of the Arctic Fox shrinks,
    giving way to the northward advance of the Red
    Fox.

33
Ediths Checkerspot Butterfly
  • Driven away from its home in search of cooler
    temperatures
  • Well known for its extreme sensitivity to climate
    changes.
  • Western regions of U.S. is where the butterfly
    has flourished
  • Currently this butterfly has failed to survive at
    the southern extremes of its range due to rising
    temperatures.

34
Ediths Checkerspot Butterfly
  • Studies show that 63 of butterflies have shifted
    their ranges 35 to 240km northward in the past
    100 years.
  • Populations of butterfly in Mexico are 4x more
  • Extinctions are also 2.5 times more likely at
    lower elevations in comparison with populations
    living above 8000 ft.

35
Gray Wolves
  • Behavioral response to increased snowfall in the
    Isle Royale National Park has a cascade effect on
    the rest of the ecosystem.
  • The climate change effect called the North
    American Oscillation has caused greater snow
    levels to fall in the Isle Royale area.
  • As a result, gray wolves are hunting in larger
    packs, killing triple the number of moose that
    they would usually kill in smaller packs.
  • Consequently, the reduction in moose population
    led to uninhibited growth of understory balsam
    fir trees since the moose were present to control
    its rate.

36
Eskimos Cope With Global Warming
37
Arctic
  • Climate scientist since the mid-1970s have
    predicted that warming would come 1st in the
    Arctic.
  • Global warming is occurring in the Arctic twice
    the rate of the world avg.
  • Parts of the Arctic have warmed by 10 degrees
    Fahrenheit.
  • Sea ice covers 15 less of the Arctic Ocean as it
    did 20 yrs. Ago
  • Arctic ice has lost an area the size of Texas
    Arizona combined

38
Inupiaq culture
  • Their Eskimo village is located on a barrier
    island
  • 600 residents
  • Have lost 100ft-300ft of coastline since 1997

39
Problems
  • As Alaskas permafrost thaws the sea is
    thinning-this leaves the Eskimos vulnerable to
    violent storms
  • Their island is eroding its now only a quarter
    mi. wide
  • The loss of summer sea ice could be as soon as
    2070-Ekimos rely on the summer harvest at the
    edge of the ice
  • Temps. Are likely to increase 4-7 degrees, which
    will cause the white reflective ice to be
    replaced by heat-absorbing darker land and ocean
    surfaces

40
Changes for Eskimos
  • Ice- fishing season has moved from Oct. to Dec.
    because the ocean is freezing later
  • Berry picking begins in July Instead of August
  • Thin ice makes it harder to hunt oogruk-the
    bearded seal that is a staple of their diet and
    culture
  • Now have longer distances and riskier journeys to
    get food

41
Changes continued
  • Gray whale has become skinny smells rancid-cant
    eat this
  • Eskimos are well prepared to craft igloos out of
    alternative materials-soil, branches whale
    blubber
  • As the Artic changes, the Ancient Inupiaq
    culture will be forced to change as well, perhaps
    becoming as unrecognizable as the new landscape.
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