1. Atmospheric CO2 & Temperature – Julie Brigham-Grette and Beth Caissie
what is normal?
Presented by
Julie Brigham-Grette and Beth Caissie
July 2010

2. CO2 and Temperature—What is Normal?
Concepts to Address before you begin
Climate vs. Weather
Greenhouse Gasses
The Carbon Cycle
Play the game?
Photosynthesis and Decomposition
Concepts to grasp During the Activity
How much of a change in CO2 concentration and other GHGs is natural?
What is the normal range of CO2 and temperature variability? How is normal defined in this context?
What is the relationship between CO2 and global temperatures?

3. Season Change in the Biosphere

4. What causes this change in annual Carbon dioxide?

5. Seasonal changes cause up/downs in CO2 in the atmosphere
Seasonal changes cause up/downs in CO2 in the atmosphere
Especially driven by Northern Hemisphere. Spring - photosynthesis drops CO2, Fall - decomposition causes increase in CO2

6. Monitoring of CO2 and other Greenhouse gases around the world
All get similar measurements
Why?

8. Global View CO2 http://www. esrl. noaa

9. Thermal drilling on Quelccaya, 2003
The ice is extruded from a core barrel – either thermal or electromechanical – then logged, slid into tubes, and packed into insulated boxes for frozen transport.
Almost all the analyses take place back in clean rooms – so if the ice is lost, so is the information.
Thermal drilling on Quelccaya, 2003 9

10. Drilling in Greenland Video podcast from Polar Palooza

11. Trapped in the ice; records past atmosphere
Matt Nolan, UAF
Fossil air!
Trapped in the ice; records past atmosphere
Summit Station, Greenland photo by Michael Morrison, GISP2 SMO, University of New Hampshire; NOAA Paleoslide SetCore: Eric Cravens, Assistant Curator, U.S. National Ice Core Laboratory;

12. Gases within bubbles = fossil atmospheric air
Raynaud, 1992
Gases within bubbles = fossil atmospheric air

13. • Depth of transition depends on surface
Firn-ice transition
• Depth of transition depends on surface
temperature and accumulation rate
• Camp Century, Greenland:
~68 m below ice sheet surface
• Vostok, Antarctica:
~100 m below ice sheet surface
Low precip. and cold = long time to make ice
High precip. and warm = short time to make ice

14. Plot by hand on graph paper, Plot on computer using Excel
Classroom options:
Plot by hand on graph paper,
Plot on computer using Excel
Overlay Temperature on CO2
Analysis:
Defining amplitude, frequency, periodicity
Defining Normal?
Understanding the relationship between Greenhouse gases and temperature.
Instructions for Excel on website

15. wikipedia art

16. 1H 2H (Deuterium) 3H (tritium) 99.98% 0.016% (bombs)
Oxygen (8 protons)
16O O O
99.8% % %
Hydrogen (1 proton)
1H H (Deuterium) H (tritium) % % (bombs)
So, can make 9 isotopic combinations of H2O,
e.g., (1H216O) to (2H218O)
“light water” “heavy water”
Isotopes are any of the different chemical species of a chemical element each having different atomic mass (mass number). Isotopes of an element have nuclei with the same number of protons (the same atomic number) but different numbers of neutrons. Therefore, isotopes have different mass numbers, which give the total number of nucleonsﾑthe number of protons plus neutrons.
In paleoclimate studies…1H1H16O to 1H218O

17. Expressed in per mille (0/00)
General Equation:
 18O = 18O/16O sample - 18O/16O standard x 1000
18O/16O standard
Expressed in per mille (0/00)
Negative values = lower ratios = isotopically lighter
(less 18O than 16O)
Positive values = higher ratios = isotopically heavier
(more 18O than 16O)

18. Glacials = enriched 18O depleted 18O
d18O isotopic depletion
-50
-40
-30
-20
Evaporation of more 16O
Ice Sheet
-10
ocean
In Sea In Ice
Glacials = enriched 18O depleted 18O
Interglacials = depleted 18O enriched 18O

19. depends on temp of source area,
dD isotopic depletion
depends on temp of source area,
Distance and processes during precipitation
Ice Sheet
ocean
The isotopic composition of water, and in particular the concentration of the heavy isotope of oxygen, 18O, relative to 16O, as well as 2H (deuterium) relative to 1H, is indicative of the temperatures of the environment. During cold periods, the concentration of less volatile 2H (18O) in the ice is lower than during warm periods. The reason for this is that at lower temperature, the moisture has been removed from the atmosphere to a larger degree resulting in an increased depletion of the heavier isotopes.
Isotopic ratios are used to model temperature, at Vostok; empirically this is roughly:
Temperature (deg-C) = (δD + 440) / 6
See also

20. mixed sources for data

21. http://earthobservatory. nasa. gov/Library/CarbonCycle/carbon_cycle4