Special Topics
Global Warming and Ocean
Acidification
Global Warming and
Ocean Acidification
The Atmosphere
• Layer of gases
surrounding the
planet
• Troposphere
–
–
–
–
Nitrogen
Oxygen
Carbon dioxide
Methane
The Greenhouse Effect
The Greenhouse Effect
Human activity releases greenhouse gases:
• Burning of fossil fuels (oil and coal) – releases ¾ of the CO2
• Deforestation
• Puts CO2 into the atmosphere by burning
• Less CO2 is absorbed by trees
• Methane is released by
• Burning fossil fuels
• Digestive system of cattle and sheep
• Rice paddies
The scale of slash and burn
agriculture in Western
Brazil is almost
incomprehensible. During
the dry season the forest is
put to the torch to make
way for unsustainable
farming and cattle raising.
Madagascar
Consequences of Global Warming
• Rising sea levels as ice caps of Greenland and
Antarctica melt
• Changes in precipitation patterns
• Changes in habitat
– The Arctic and Antarctic are warming 2-3X the
global rate
• Loss of ice results in further warming
– Bright white ice reflects solar energy back to space
– Dark open water absorbs heat
Global Warming Animation
Global Warming and Polar Bears
6CO2 + 6H2O + E
C6H12O6 + 6O2
C6H12O6 + 6O2
6CO2 + 6H2O + ATP
Increased CO2 in the ocean
results in acidification of the
Ocean.
Ocean acidification: NRDC
CO2 highly soluble in sea
water. The oceans hold more
than 50X more CO2 than the
atmosphere.
Baleen Whales
Crabeater Seals
Leopard Seals
Adelie Penguins
Chinstrap Penguins
Gentoo Penguins
Krill – Euphausia superba
Phytoplankton
Light E
Photosynthesis
Food E
The top
predators of the
Antarctic
Peninsula are
seabirds and
seals.
The Crabeater Seal is a Krill Specialist
Crabeater seals are krill specialists.
Their entire “terrestrial” existence is
spent on ice floes, not land.
South
North
Gentoos
Chinstraps
Adelies
The distribution of Chinstrap Penguins
is intermediate between the Gentoo
Penguin in the north and the Adelie
Penguin in the south.
Adelie Penguins
Adelie penguins breed on shores around
the Antarctic continent, South Shetland,
South Orkney, and South Sandwich Islands.
At sea they are usually found near the edge
of the shelf-ice to the northern extent of
the pack-ice. They are a krill dependant
species.
On the western side
of the Antarctic
Peninsula the ACC
upwells and floods
onto the continental
shelf. This brings
nutrients to the coastal
waters leading to
blooms of diatoms
that krill feel on.
Upwelling
Some of the larval stages of krill feed on algae that grow on
the lower surface of sea ice. One of the factors that
determines the annual abundance of krill is the
extent of sea ice in winter. Along the northern half of the
Antarctic Peninsula there has been an 80% decline in
krill abundance in the past 30 years attributed to a
loss of sea ice.