This is a NASA satellite image showing Lake Tanganyika, East Africa
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Transcript This is a NASA satellite image showing Lake Tanganyika, East Africa
This is a NASA satellite image showing Lake Tanganyika, East Africa
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 planet’s
liquid fresh water)
• Famous for its extraordinary north (Burundi) to south (Zambia)
extension of 670 km, and width of 50 km.
• It’s mean depth is 570 m. & maximum depth of 1,470 m.
• Bordering countries include Burundi, Tanzania, Zambia, Zimbabwe
and the Democratic Republic of Congo.
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, it’s 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.
• 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 Tanganyika’s food chain, which
ultimately feeds the commercially important fish.
• Algae abundance has declined ~20 percent.
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
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 region’s
people who depend heavily on the lake as a natural
resource.
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.
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
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
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
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
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
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
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, RedWinged Blackbirds, American Lobsters,
First Species Extinction Due to
Global Warming
• The Golden Toads
which are known only
to inhabit Costa Rica’s
Monteverde Cloud
Forest have
disappeared.
• Amphibians are
especially succeptible
to climate changes
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.
Climate Change Impacts in the
Eastern Carribean
• Carribean Countries are extremely
vulnerable to climate change.
Causes of Vulnerability
•
•
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•
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•
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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
Climate Change Variations
• Sea level rise of 2 mm/year
• Temperature & percipitation
-change in weather patterns
(Precipitation)
-causes extreme events
-hurricanes
Natural Disasters
• (floods, drought,
landslides,
hurricanes)s
- Hurricane Ivan
(2004)
-Hurricane Jeannie
(2004)
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
Resources at Risk
• Coastal infrastructure
• Human settlements
-Up to 90% settlement
• Utilities
• Roads
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
Consequences of Sea Level
Rising
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Beach erosion
Destruction of freshwater habitats
Increase of storms
Degradation of mangroves, sea grass bed,
coral reef
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.
Tree Swallows Cont’d
• Birds use temperature as a sign to start nesting
partly because it’s a good predictor of the timing
of food supplies for their young.
• If the emergence of insects doesn’t 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.
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.
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.
Edith’s 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.
Edith’s 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.
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.
Eskimos Cope With Global
Warming
Arctic
• Climate scientist since the mid-1970’s 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
Inupiaq culture
• Their Eskimo village
is located on a barrier
island
• 600 residents
• Have lost 100ft-300ft
of coastline since
1997
Problems
• As Alaska’s permafrost thaws the sea is
thinning-this leaves the Eskimo’s 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-Ekimo’s 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
Changes for Eskimo’s
• 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 oogrukthe bearded seal that is a staple of their
diet and culture
• Now have longer distances and riskier
journeys to get food
Changes continued…
• Gray whale has become skinny & smells
rancid-cant eat this
• Eskimo’s 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.”