ANTARCTICA: COLD AND FULL OF PENGUINS

Jack Breese, Josh Cranmer

PENGUINS

• OH GOD THERE ARE SO MANY!

PENGUIN FACTORY

• This is where they make penguins.

Antarctic Climate Cooling and Terrestrial Ecosystem Response• “From 1982 to 2000 central Antarctic

valleys cooled .7°C per decade with serious economic damage from cold.”

• There is uncertainty as to whether or not the average temperature in the Antarctic is rising or falling.

Climate and atmospheric history of the past 420,000 years from the Vostok ice core, Antarctica

• “During the last four interglacials, going back 420,000 years, the Earth was warmer than it is today.”

• According to the article, only two of the last four interglacials were warmer.

Interpretation of recent Antarctic sea ice variability

• “Antarctic sea ice has increased since 1979.”

• The article confirms this.• Variations are due to El Niño and Antarctic

Oscillation.

Interpretation of recent Southern Hemisphere climate change

• “Antarctic peninsula has warmed several degrees while interior has cooled somewhat. Ice shelves have retreated but sea ice has increased.”

• “During the summer-fall season, the trend toward stronger circumpolar flow has contributed substantially to the observed warming over the Antarctic Peninsula and Patagonia and to the cooling over eastern Antarctica and the Antarctic plateau.”

Positive Mass Balance of the Ross Ice Streams, West

Antarctica• “Side-looking radar measurements show

West Antarctic is increasing at 26.8 Gtons/yr. Reversing the melting trend of the last 6,000 years.”

• Evidence shows annual ice sheet growth of over 25 gigatons per year in the Ross Ice Streams.

• This is in contrast with the previous estimates of annual shrinkage of ~20 gigatons per year.

Radiocarbon constraints on ice sheet advance and retreat in the

Weddell Sea, Antarctica• “Less Antarctic ice has melted today than

occurred during the last interglacial.”• Prior to the last glacial maximum, there was

significant glacial shrinkage.• There is more ice now than there was at

the previous glacial minimum.

Trends in the length of the Southern Ocean sea-ice season,

1979-99• “The grater part of Antarctica experiences a

longer sea-ice season, lasting 21 days longer than it did in 1979.”

• Some parts of the Antarctic have experienced a lengthening of the sea-ice season, and others a shortening.

• Overall 46% more of the Southern Ocean is experiencing a lengthening of the sea-ice season.

Conclusion

• On the whole, Crichton does tend to represent the articles correctly

• The articles he cites are representative of Antarctica:– West Antarctica is in varying stages of retreat– East Antarctica (the larger part) is advancing