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http://motls.blogspot.com/2006/07/carbon-dioxide-and-temperatures-ice.html
2009/3/26Pei-Yu Chueh
CO2 vs temperature: ice core correlation & lag
Lubos
Outline
• How to reconstruct the past climate?
• Objection: An Inconvenient Truth
• Some questions
• Possible explanation
• Others’ comments
Vostok ice core, Antarctica
Temp↑δD↑
Correlations between the temp. and the concentrations extracted from the ice
core
An Inconvenient Truth
• Al Gore's answer : the temperature was determined by the concentrations of carbon dioxide.
Some questions
1. All the correlations in a satisfactory way.
If you choose one of the gases, your explanation will be asymmetric and it won’t explain all the correlations in a satisfactory way
Some questions
• 2.Basic numbers
ice age 180ppm
Interglacials 280ppm
100ppm
+8℃
280ppm in 1800
380ppm in 2005
+0.7 ℃
100ppm
Some questions
• 3. 1940~1975 economic boom
CO2 ↑
but temp ↓
The Great Global Warming Swindle
Possible explanation
1. Coke in a car
Originally contains 4 volumns of CO2
CO2 leaks a bit
internal volume is 1 cube meter
Coke385ml
CO2
(106 ml)
CO2CO2CO2CO2
Possible explanation
Henry’s law : Hot liquids are not able to absorb gases so well.
Warmer ocean
outgassing
Possible explanation
2. The frequency of fires
Temp↑ Frequency of fires ↑ CO2 ↑
3. The growth of plants and animals depends on temperature
4. Physics tells you quite clearly that the ability of water to bind gases is more important an effect for the correlation than the greenhouse effect
Possible explanation
5. CO2 lagged behind the temp about 800 years
now past
Possible explanation
800 years↑CO2
↑temperature
• oceans are large and it simply takes centuries for them to warm up or cool down before they release or absorb gases.
Possible explanation
• 19,000-17,000 years ago : deep sea temperatures increased by 2 Celsius degrees or so
• 1,000 years later : CO₂ increases
Lowell Stott, Axel Timmermann, Robert Thunell: "Southern Hemisphere and Deep-Sea Warming Led Deglacial Atmospheric CO₂ Rise and Tropical Warming"
Possible explanation
• Not only the CO₂ lags by 1,000 years but the sea surface temperatures in the tropics lag, too.
• The deep ocean warmed much earlier than the surface.
Lowell Stott, Axel Timmermann, Robert Thunell: "Southern Hemisphere and Deep-Sea Warming Led Deglacial Atmospheric CO₂ Rise and Tropical Warming"
• The warm water came from the South
• Perhaps “increasing southern spring insolation” occured
• Followed by albedo feedback
Possible explanation
• Also, it is believed that the 800-year period is also the mixing time for the deep ocean.
• There is a limit to the amount of natural CO2 that can be released
→making a never-ending cycle of temperature increase unlikely
Never-ending increasing?
X 50
Others’ comments
• Sun controls cosmic ray
• Sunspot activity↑
• Cosmic ray↓
• Clouds↓
• More energy gets to the ground
• Ground heats up
• Temperature↑
Charles Jordan said…
Others’ comments
Average sunspot activity has been going up and can account for most of the heating we see in the last 50 years.
The Great Global Warming Swindle
The End ~