Thermal maximum

Thermal maximum demand ammeters 4 to 8 VA Power factor (p.f.) meters 5 VA... 

Ravizza G, Norris RN, Blusztajn J, Aubry MP (2001) An osmium isotope excursion associated with the late Paleocene thermal maximum Evidence of intensified chemical weathering. Paleoceanogr 16 155-163 Raymo ME (1991) Geochemical evidence supporting Chamberlain, T. C., theory of glaciation. Geology 19 ... 

Paleocene eocene thermal maximum (PETM) A hyperthermal period, 55.8mybp, during which average global temperatures increased by 6°C for a period of 20,000 years. 

As has been proposed by numerous studies (e.g., Rohl et al. 2000 Dickens 2003) the massive release of gas hydrates could modify climate. The best example for this hypothesis are sedimentary rocks deposited at around 55 Ma during the Paleocene-Eocene thermal maximum, where a decrease of 2-3%c in carbonate-carbon is interpreted as a consequence of an abrupt thermal release of gas-hydrate methane and its subsequent incorporation into the carbonate pool. 

Fig. 3.49 Global deep-sea isotope record from numerous DSDP and ODP cores. PETM Paleocene-Eocene Thermal Maximum (Zachos et al. 2001)...

Katz, M. E. Pak, D. K. Dickens, G. R. Miller, K. G. (1999). The source and fate of massive carbon input during the latest paleocene thermal maximum. Science, 286, 1531. 

Dickens, G.R., Modeling the Global Carbon Cycle with a Gas Hydrate Capacitor Significance for the Latest Paleocene Thermal Maximum. Natural Gas Hydrates Occurrence, Distribution, and Detection (Pauli, C.K., Dillon, W.P., eds.), AGU, Washington, DC, Geophys. Monogr. Ser. 124, pp. 19-38 (2001). 

Methane clathrate decomposition has been implicated in the Latest Paleocene Thermal Maximum (—55 Ma ago) by an extraordinary injection of isotopically light carbon into the carbon cycle (Dickens, 2000, 2001a) and in Quaternary interstadials as indicated by observations of isotopically light foraminifera in Santa Barbara Basin sediments (Kennett et al., 2000). Dickens (2001a) compares the functioning of the CH4 hydrate to a bacterially mediated capacitor. 

Dickens G. R. (2000) Methane oxidation during the late paleocene thermal maximum. Bull. Soc. Geol. Fr. 171,... 

Rdhl U., Bralower T. J., Norris R. D., and Wefer G. (2(X)0) New chronology for the Late Paleocene thermal maximum and its environmental implications. Geology 28, 927-930. 

About 55 Myr ago, a brief period known as the Late Paleocene thermal maximum (Zachos et al., 1993) is defined in marine and terrestrial records by a sudden increase in proxy temperature estimates and a very large decrease in the ratio of to (Figure 13). Most of the carbon isotope shift appears to have occurred within a period of a few thousand years (Norris and Rohl, 1999), suggesting that the cause might have been a redistribution of carbon from the terrestrial biosphere to the oceans and atmosphere. But the magnitude of the shift, —2.5%o to —3%o, would have required the transfer of an amount of terrestrial organic carbon equivalent at least to virtually the entire modem terrestrial biosphere,... 

Figure 13 High-resolution carbon isotope records showing the anomaly corresponding to the Late Paleocene Thermal Maximum. The data are from three widely separated Ocean Drilling Program cores (Kennett and Stott, 1991 Bralower et al., 1995 Bralower et al., 1997) plotted on a common depth scale with the minimum at 0.0 m (Dickens (2001) reproduced by permission of the American Geophysical Union from Natural Gas Hydrates Occurrence, Distribution, and Detection, 2001, pp. 19-38 (figure 1)).

Bralower T. J., Thomas D. J., Zachos J. C., Hirschmann M. M., Rohl U., Sigurdsson H., Thomas E., and Whitney D. L. (1997) High-resolution records of the late Palaeocene thermal maximum and circum-Caribbean volcanism is there a causal link Geology 25, 963—966. 

Dickens G. R. (2001) Modeling the global carbon cycle with a gas hydrate capacitor significance for the Latest Paleocene Thermal Maximum. In Natural Gas Hydrates Occurrence, Distribution, and Detection Geophysical Monograph 124 (eds. C. K. Pauli and W. P. Dillon). American Geophysical Union, Washington, DC, pp. 19—38. 

Kelly D.C. (2002) Response of Antarctic (ODP Site 690) planktonic foraminifera to the Paleocene-Eocene thermal maximum faunal evidence for ocean/climate change. Paleoceanogr. 17, 1071, doi 10.1029/2002PA000761. 

Kelly D.C., Bralower T.J., Zachos J.C., Permoli Silva I., Thomas E. (1996) Rapid diversification of planktonic foraminifera in the tropical Pacific (ODP site 865) during the late Paleocene thermal maximum. Geology 24, 423-6. 

Thomas D.J., ZachosJ.C., BralowerT.J., Thomas E., Bohaty S. (2002) Warming the fuel for the fire evidence for the thermal dissociation of methane hydrate during the Paleocene—Eocene thermal maximum. Geology 30, 1067— 70. 

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