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					  Mismatch of CO2 and Earth's
temperatures ~35 million cyclicity
 over the last 420 million years


            Andreas Prokoph
   Carleton University, Ottawa, Canada
                              Topic:

Compare cycles and trends of reconstructed Earth’s
Global temperature and atmospheric CO2 at
currently best-possible temporal resolution (>20 Myr)

~35Myr –cycle major importance in Earth’s history:

Occurs in large volcanic eruptions, meteorite impacts, major
extinctions, sea-level change and marine anoxic conditions

                       Temperate proxy Data used:
 ~24,000 Oxygen isotope data from non-altered marine fossil
 carbonate (Prokoph, Shields & Veizer, 2008 + ~2000 new data)


                   Atmospheric CO2 proxy Data used:
 ~500 fossil proxy data from fossil plants and others
                  (Royer et al., 2006)
                                          Previous Correlation
                                  (CO2-temperature mismatch >100 Myr)
                                                                     GEOCARB III model
                                                                     Berner and Kothalava, 2003)
       6000
                               Royer et al. 2006

  4000
pCO2
(ppm)
       2000



                     0
                                                      Cosmic Ray Flux (Shaviv and Veizer, 2004)
                 0
    f(t)/f(0)




                                                                                                            Glaciations
                 1




                                                                                                                           warming
                                                                                                                 -1

                 2
                                                                        Prokoph et al., 2008
                                                                                                                 0
                                                                                                                      d O
                                                                                                                      18
                22
o                                                                                                                1
C               17
                                   Climate record (Scotese)




                                                                                                                            cooling
                12                                                                                               2


                         0       50     100     150    200     250     300    350     400      450    500     550 Ma
                             Tertiary Cretaceous Jurassic   Trias Perm Carbonifer Devon     Silur Ordov. Camb.
         Data analysis methodology

•   Trend and Regression Analysis
•   Wavelet Analysis
•   Cross-Wavelet Analysis
•   Spectral Analysis
•   Stratigraphic (“time”) filtering
Gaussian probabilities                 18
                                         O %0
                                      d13C ‰                              18
(uncertianties) of sample ages                                             O
                                 (probability weighted)
                                                                               Sample variability and age uncertainty




                                          Age-uncertainty-filtered data
 6


 3


 0




                                                                                                                                   cooling
-3


-6




                                                                                                                                   warming
-9


-12


-15
      0         50        100         150         200         250     300        350         400       450       500        550 Ma
          Tertiary   Cretaceous Jurassic              Trias     Perm Carbonifer Devon          Silur Ordov. Camb.


benthic foraminifera            high-latitude brachiopods             tropical planktic foraminifera    mid-latitude planktic foraminifera
subtropical brachiopods         high-latitude planktic foraminifera   tropical belemnites               mid-latitude belemnites
subtropical belemnites          high-latitude belemnites              tropical brachiopods              mid-latitude brachiopods
                                                                                                        other fossils
                            Filtered temperature record


                    50Myr moving averaged                     linear detrended compiled tropical
    20              linear detrended                           paleotemperature record
                    paleotemperature record


    10
o
    C
     0


    -10


          0         50      100     150       200       250   300      350      400       450      500   550 Ma

              Tertiary   Cretaceous Jurassic    Trias    Perm Carbonifer Devon      Silur Ordov. Camb.
                           Filtered atmospheric CO2
6000



4000
pCO2
(ppm)
2000



  0


        0         50      100     150    200         250   300     350    400     450    500       550 Ma
            Tertiary   Cretaceous Jurassic   Trias    Perm Carbonifer Devon   Silur Ordov. Camb.
                                                  Wavelet analysis                                   Wave
                                                                                                     Amplitude
                     5
                    10                                                                               3.2

                    20
                                                          ~35 Myr                                           o
                                                                                                            C
Wavelength in Myr




                    50
                    100
                                                       ~125±20 M a
                    200



                     5                                                                               1000
                    10
                                 Atmospheric CO2 record
                    20
                                                                                                            ppm
                                                          ~35 Myr
                    50
                    100
                    200                               ~260±50 M a                                     0

                          0         50      100     150    200     250    300     350    400 Ma
                              Tertiary   Cretaceous Jurassic   Trias Perm Carbonifer Devon   Silur
                                           Cross-wavelet analysis
                                                pCO2 x temperature
                    5




                                                        Phase change
                                                                                                                          200
Wavelength in Myr




                                                                                                                                cross amplitude
                                                                                                              ~35 Myr


420                                                                                        cross amplitude
                                                                                                                           0
                5
                                                                                                                            p
Wavelength in Myr




                                                                                                               ~35 Myr




                                                                                                                                phase
                                                                                                     phase                 -p
420

                        0         50      100     150            200           250   300       350     400 Ma
                            Tertiary   Cretaceous Jurassic             Trias    Perm Carbonifer Devon        Silur Ordov. Camb.
               Reconstruction of amplitudes and phase-difference
               of ~35Myr pCO2 and temperature cyclicity


          pCO2 follows                              pCO2 leads temperature
          temperature
 10000                                                                          pCO2 (in ppm)
    1000
      100
                                                                                            o
                                                                            temperature ( C)
          10
          1

          2
radians




          0
                                                    Phase offset CO2-temperature
          -2

               0         50      100     150    200         250   300     350      400 Ma
                   Tertiary   Cretaceous Jurassic   Trias    Perm Carbonifer Devon    Silur Ordov. Camb.
    Reconstruction of ~35Myr pCO2 and temperature cyclicity

           pCO2 follows                                     pCO2 leads temperature




                                       phase change
           temperature

    2500
ppm
    1500


    500




                                                                       glaciation
     34


     30
o
C
     26


           0         50      100     150              200       250   300           350   400 Ma
               Tertiary   Cretaceous Jurassic           Trias    Perm Carbonifer Devon      Silur Ordov. Camb.
                       Conclusions

• Until ~200 million years ago, CO2 may have be a
  driver of global temperature change at 100ppm/1ºC
  at the 35Myr cycle band

• In the last ~150Myr CO2 follows global temperature

• Potential causes for the change:
De-Coupling of hydrological from carbon cycle due to new major C-
   sink: plankton in open ocean after ~200Myr
More frequent volcanism? (Prokoph et al., 2004)

				
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