Ice volume change

Sowers T, Bender M, Raynaud D, Korotkevich YS, Orchardo J (1991) The 6 0 of atmospheric O2 from air inclusions in the Vostok ice core timing of CO2 and ice volume changes during the Penultimate degladation. Paleoceanography 6 679-696... 

The Mg/Ca and of benthic foraminifers are both influenced by the temperature of calcification. This link is the reason that a discussion of Mg/Ca is included in this review. As outlined above, the oxygen isotope composition of biogenic calcite is a function of the temperature and the oxygen isotope composition of the water in which the organism calcified. For benthic foraminiferal records it is widely assumed that mainly the ice volume changes drive the temporal variations in the of... 

Lorius et al. (1990) performed a simple multivariate analysis in which they correlate the temperature changes of the past 160 kyr (as recorded in the Vostok SD record) with changes in five forcings atmospheric CO2 plus CH4, ice volume, aerosol loading (dust and sepa-... 

In the previous studies it was considered that the climate change has been reflected by the changes in ocean circulation pattern, ice volume, albedo, and weathering. Many... 

Fig. 4.14. Tracing climate change in the Miocene. Shown here are records of ice volume and temperature (based on foraminiferal S 0) and relative organic carbon burial (based on foraminiferal S C), compared with the CO2 estimates of Pagani et al. (1999), and tectonic events that may have affected ocean heat transport. Trends in CO2 are consistent with organic carbon burial and CO2 drawdown during the Monterey Excursion, but cannot explain the Miocene Climatic Optimum (MCO) or expansion of the East Antarctic Ice Sheet (EAIS).

Recognizing Cause and Effect If the mass remains constant for the water and ice but the volume changes, explain how this will affect the density. 

The variation of the phase transition temperature with pressure can be calculated from the knowledge of the volume and enthalpy change of the transition. Most often both the entropy and volume changes are positive and the transition temperature increases with pressure. In other cases, notably melting of ice, the density of the liquid phase is larger than of the solid, and the transition temperature decreases... 

Milankovitch cycles Changes in global ice volume that reach maxima every 23,000, 41,000, and 100,000 years. They are thought to be related to changes in astronomical alignments that have similar periods. 

It is expected that the temperature of deep-water masses is more or less constant, as long as ice caps exist at the poles. Thus, the oxygen isotope composition of benthic organisms should preferentially reflect the change in the isotopic composition of the water (ice-volume effect), while the 5 0-values of planktonic foraminifera are affected by both temperature and isotopic water composition. 

Variations in the benthic foraminifera record after 33 Ma indicate fluctuations in global ice volume in addition to temperature changes. Since then the majority of the 5 0 variations can be attributed to fluctuations in the global ice volume. Thus, Tiedemann et al. (1994) demonstrated the presence of at least 45 glacial-interglacial cycles over the last 2.5 Ma. 

A 17 Ma trend toward cooler conditions followed, as expressed by a 3%c rise in 5 0, which can be attributed to a 7°C decline in deep-sea temperatures. All subsequent changes reflect a combined effect of ice-volume and temperature. 

The quasi-steady-state theory has been applied particularly where a condensed phase exists whose volume changes slowly with time. This is true, for example, in the sublimation of ice or the condensation of water vapor from air on liquid droplets (M3, M4). In the condensation of water vapor onto a spherical drop of radius R(t), the concentration of water vapor in the surrounding atmosphere may be approximated by the well-known spherically symmetric solution of the Laplace equation ... 

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