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Paleogeography and climate
OLR (1983) 30 (6)
D. Submarine Geology and Geophysics
Numerical experiments are used to examine the effect of the equator-to-pole surface temperature gradient and geography on Cretaceous atmospheric paleocirculation. There is, in these model results, no strong decrease of circulation due to reduced temperature gradient; however, there is evidence for strong geographic control. Results raise questions about the two classical paleoclimate hypotheses: i.e., during 'warm' periods, surface currents and winds were 'sluggish' and large-scale features (e.g., the westerlies) were displaced poleward. Paleoclimatic Stud. Prog., NCAR, Boulder, Colo. 80307, USA. (ifP) 83:3327 Barron, E.J. and W.M. Washington, 1982. Cretaceous climate: a comparison of atmospheric simulations with the geologic record. Palaeogeogr.
Palaeoclimatol. Palaeoecol., 40(1/3): 103-133. Simulated Cretaceous atmospheric circulations differ from the present-day pattern and do not support the classical hypothesis of 'weaker circulation and poleward displacement of circulation features.' A comparison of simulations utilizing Cretaceous geography and temperatures to modelled presentday conditions suggests 'that paleogeography is an important factor governing...the circulation.' Paleoclimatic Stud. Prog., NCAR, Boulder, Colo. 80307, USA. (msg) 83:3328 Barron, E.J. (ed.), 1981/82. Paleogeography and dlmate. Meeting, Cincinnati, 1981. Special issue.
Palaeogeogr.
Palaeoclimatol.
Palaeoecol.,
40(1/3):1-253; 11 papers. GSA's annual meeting dealt primarily with the relationships between paleogeographic factors and climate. Papers addressed the climates of specific geological time intervals (Archean, Late Triassic, Cretaceous); Mesozoic and Cenozoic atmospheric circulation and rainfall models; anoxia in the deep-sea environment; the paleogeography and circulation of the Arctic Basin; the influence of the North Atlantic on deep oceanic circulation; and the deglacial build-up of CO2. (hbf) 83:3329 Berger, W.H., 1982. Deglaelal CO z buildup: constralnts on the coral-reef model. Palaeogeogr. PalaeoclimatoL PalaeoecoL, 40(1/3):235-253. The transgressive coral-reef model, aided by the Worthington Effect, accounts for about half of the deglacial atmospheric CO2 increase and explains the Holocene dissolution pulse. Decreased oceanic fertility should account for the missing CO 2. Scripps
451
Inst. of Oceanogra., La Jolla, Calif. 92093, USA. (msg) 83:3330 Broecker, W.S., 1982. Glacial to interglacial changes in ocean chemistry. Prog. Oceanogr., 11(2):151197. If atmospheric CO2 content is substantially higher at present than during the last glacial period, as suggested by tantalizing evidence from polar ice cores, then the change must have been induced by a change in oceanic chemistry, suggested here to have been higher PO 4 concentrations responsible for reduced CO 2 partial pressure in the glacial ocean. Post-glacial PO 4 absorption by increased volumes of organic-rich shelf sediments is believed responsible for subsequent reversal of the process. Includes appendixes on the CaCO3/Corg rain rate ratio, the 8J3C-PO4 relationship, and the C/P ratio in organic debris being oxidized in the deep sea. LamontDoherty Geol. Observ., Palisades, N.Y. 10964, USA. (fcs) 83:3331 Burckle, L.H., L.D. Keigwin and N.D. Opdyke, 1982. Middle and Late Miocene stable Isotope
stratigraphy: correlation to the paleomagnetic reversal record. Mieropaleontology, 28(4):329334. Late Miocene oxygen isotope stratigraphy for DSDP Site 158 (eastern equatorial Pacific) reveals two oxygen isotope events reflecting growth of the East Antarctic Ice Sheet; they are correlated to the lower parts of Magnetic Epochs 11 and 10 (~11 and 10 Ma, respectively). Lamont-Doherty Grol. Observ., Palisades, NY 10964, USA. 83:3332 Crittenden, S., 1982. Lower Cretaceous lithostratigraphy NE of the sole pit area in the U.K. southern North Sea. J. Petrol. Geol., 5(2):191-201. Dept. of Geol., Plymouth Polytechnic, Drake Circus, Plymouth, Devon PL4 8AA, UK. 83:3333 Dansgaard, W. et al., 1982. A new Greenland deep ice core. Science, 218(4579): 1273-1277. A new ice core from south Greenland presents a continuous sequence of data on atmospheric conditions back to ~90,000 yrBP, based on comparisons with the oxygen isotopic profile of the northwest Greenland Camp Century core and the deep-sea foraminiferal record. An abrupt, dramatic termination of the Eem/Sangamon interglacial is
D. Submarine Geology and Geophysics
Numerical experiments are used to examine the effect of the equator-to-pole surface temperature gradient and geography on Cretaceous atmospheric paleocirculation. There is, in these model results, no strong decrease of circulation due to reduced temperature gradient; however, there is evidence for strong geographic control. Results raise questions about the two classical paleoclimate hypotheses: i.e., during 'warm' periods, surface currents and winds were 'sluggish' and large-scale features (e.g., the westerlies) were displaced poleward. Paleoclimatic Stud. Prog., NCAR, Boulder, Colo. 80307, USA. (ifP) 83:3327 Barron, E.J. and W.M. Washington, 1982. Cretaceous climate: a comparison of atmospheric simulations with the geologic record. Palaeogeogr.
Palaeoclimatol. Palaeoecol., 40(1/3): 103-133. Simulated Cretaceous atmospheric circulations differ from the present-day pattern and do not support the classical hypothesis of 'weaker circulation and poleward displacement of circulation features.' A comparison of simulations utilizing Cretaceous geography and temperatures to modelled presentday conditions suggests 'that paleogeography is an important factor governing...the circulation.' Paleoclimatic Stud. Prog., NCAR, Boulder, Colo. 80307, USA. (msg) 83:3328 Barron, E.J. (ed.), 1981/82. Paleogeography and dlmate. Meeting, Cincinnati, 1981. Special issue.
Palaeogeogr.
Palaeoclimatol.
Palaeoecol.,
40(1/3):1-253; 11 papers. GSA's annual meeting dealt primarily with the relationships between paleogeographic factors and climate. Papers addressed the climates of specific geological time intervals (Archean, Late Triassic, Cretaceous); Mesozoic and Cenozoic atmospheric circulation and rainfall models; anoxia in the deep-sea environment; the paleogeography and circulation of the Arctic Basin; the influence of the North Atlantic on deep oceanic circulation; and the deglacial build-up of CO2. (hbf) 83:3329 Berger, W.H., 1982. Deglaelal CO z buildup: constralnts on the coral-reef model. Palaeogeogr. PalaeoclimatoL PalaeoecoL, 40(1/3):235-253. The transgressive coral-reef model, aided by the Worthington Effect, accounts for about half of the deglacial atmospheric CO2 increase and explains the Holocene dissolution pulse. Decreased oceanic fertility should account for the missing CO 2. Scripps
451
Inst. of Oceanogra., La Jolla, Calif. 92093, USA. (msg) 83:3330 Broecker, W.S., 1982. Glacial to interglacial changes in ocean chemistry. Prog. Oceanogr., 11(2):151197. If atmospheric CO2 content is substantially higher at present than during the last glacial period, as suggested by tantalizing evidence from polar ice cores, then the change must have been induced by a change in oceanic chemistry, suggested here to have been higher PO 4 concentrations responsible for reduced CO 2 partial pressure in the glacial ocean. Post-glacial PO 4 absorption by increased volumes of organic-rich shelf sediments is believed responsible for subsequent reversal of the process. Includes appendixes on the CaCO3/Corg rain rate ratio, the 8J3C-PO4 relationship, and the C/P ratio in organic debris being oxidized in the deep sea. LamontDoherty Geol. Observ., Palisades, N.Y. 10964, USA. (fcs) 83:3331 Burckle, L.H., L.D. Keigwin and N.D. Opdyke, 1982. Middle and Late Miocene stable Isotope
stratigraphy: correlation to the paleomagnetic reversal record. Mieropaleontology, 28(4):329334. Late Miocene oxygen isotope stratigraphy for DSDP Site 158 (eastern equatorial Pacific) reveals two oxygen isotope events reflecting growth of the East Antarctic Ice Sheet; they are correlated to the lower parts of Magnetic Epochs 11 and 10 (~11 and 10 Ma, respectively). Lamont-Doherty Grol. Observ., Palisades, NY 10964, USA. 83:3332 Crittenden, S., 1982. Lower Cretaceous lithostratigraphy NE of the sole pit area in the U.K. southern North Sea. J. Petrol. Geol., 5(2):191-201. Dept. of Geol., Plymouth Polytechnic, Drake Circus, Plymouth, Devon PL4 8AA, UK. 83:3333 Dansgaard, W. et al., 1982. A new Greenland deep ice core. Science, 218(4579): 1273-1277. A new ice core from south Greenland presents a continuous sequence of data on atmospheric conditions back to ~90,000 yrBP, based on comparisons with the oxygen isotopic profile of the northwest Greenland Camp Century core and the deep-sea foraminiferal record. An abrupt, dramatic termination of the Eem/Sangamon interglacial is