The major cause of sea-level change during ice ages is the exchange of water between ice and ocean and the planet's dynamic response to the changing surface load. Inversion of ∼1,000 observations for the past 35,000 y from localities far from former ice margins has provided new constraints on the fluctuation of ice volume in this interval. Key results are: (i) a rapid final fall in global sea level of ∼40 m in <2,000 y at the onset of the glacial maximum ∼30,000 y before present (30 ka BP); (ii) a slow fall to −134 m from 29 to 21 ka BP with a maximum grounded ice volume of ∼52 × 10 6 km 3 greater than today; (iii) after an initial short duration rapid rise and a short interval of near-constant sea level, the main phase of deglaciation occurred from ∼16.5 ka BP to ∼8.2 ka BP at an average rate of rise of 12 m·ka −1 punctuated by periods of greater, particularly at 14.5-14.0 ka BP at ≥40 mm·y −1 (MWP-1A), and lesser, from 12.5 to 11.5 ka BP (Younger Dryas), rates; (iv) no evidence for a global MWP-1B event at ∼11.3 ka BP; and (v) a progressive decrease in the rate of rise from 8.2 ka to ∼2.5 ka BP, after which ocean volumes remained nearly constant until the renewed sea-level rise at 100-150 y ago, with no evidence of oscillations exceeding ∼15-20 cm in time intervals ≥200 y from 6 to 0.15 ka BP.he understanding of the change in ocean volume during glacial cycles is pertinent to several areas of earth science: for estimating the volume of ice and its geographic distribution through time (1); for calibrating isotopic proxy indicators of ocean volume change (2, 3); for estimating vertical rates of land movement from geological data (4); for examining the response of reef development to changing sea level (5); and for reconstructing paleo topographies to test models of human and other migrations (6). Estimates of variations in global sea level come from direct observational evidence of past sea levels relative to present and less directly from temporal variations in the oxygen isotopic signal of ocean sediments (7). Both yield modeldependent estimates. The first requires assumptions about processes that govern how past sea levels are recorded in the coastal geology or geomorphology as well as about the tectonic, isostatic, and oceanographic contributions to sea level change. The second requires assumptions about the source of the isotopic or chemical signatures of marine sediments and about the relative importance of growth or decay of the ice sheets, of changes in ocean and atmospheric temperatures, or from local or regional factors that control the extent and time scales of mixing within ocean basins.Both approaches are important and complementary. The direct observational evidence is restricted to time intervals or climatic and tectonic settings that favor preservation of the records through otherwise successive overprinting events. As a result, the records become increasingly fragmentary backward in time. The isotopic evidence, in contrast, being recorded in deep-water carbonate marine sediments, extends further...

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[1] Two-dimensional paleotidal simulations have been undertaken to investigate tidal and tide-dependent changes (tidal amplitudes, tidal current velocities, seasonal stratification, peak bed stress vectors) that have occurred in the NW European shelf seas during the last 20 ka. The simulations test the effect of shelf-wide isostatic changes of sea level by incorporating results from two different crustal rebound models, and the effect of the ocean-tide variability by setting open boundary values either fixed to the present state or variable according to the results of a global paleotidal model. The use of the different crustal rebound models does not affect the overall changes in tidal patterns, but the timing of the changes is sensitive to the local isostatic effects that differ between the models. The incorporation of ocean-tide changes greatly augments the amplitude of tides and tidal currents in the Celtic and Malin seas before 10 ka BP, and has a large impact on the distribution of seasonally stratified conditions, magnitude of peak bed stress vectors and tidal dissipation in the shelf seas. The predictions on seasonal stratification are supported by well-dated evidence on tidal mixing front migration in the Celtic Sea. Additional experiments using the global model suggest that the variability of offshore tides has been caused mainly by changes of eustatic sea level and ice-sheet extent. In particular, a large decrease observed at 10-8 ka BP is attributed to the opening of Hudson Strait accompanied by the retreat of the Laurentide Ice Sheet.

Using glacial rebound models we have inverted observations of crustal rebound and shoreline locations to estimate the ice thickness for the major glaciations over northern Eurasia and to predict the palaeo‐topography from late MIS‐6 (the Late Saalian at c. 140 kyr BP) to MIS‐4e (early Middle Weichselian at c. 64 kyr BP). During the Late Saalian, the ice extended across northern Europe and Russia with a broad dome centred from the Kara Sea to Karelia that reached a maximum thickness of c. 4500 m and ice surface elevation of c. 3500 m above sea level. A secondary dome occurred over Finland with ice thickness and surface elevation of 4000 m and 3000 m, respectively. When ice retreat commenced, and before the onset of the warm phase of the early Eemian, extensive marine flooding occurred from the Atlantic to the Urals and, once the ice retreated from the Urals, to the Taymyr Peninsula. The Baltic‐White Sea connection is predicted to have closed at about 129 kyr BP, although large areas of arctic Russia remained submerged until the end of the Eemian. During the stadials (MIS‐5d, 5b, 4) the maximum ice was centred over the Kara‐Barents Seas with a thickness not exceeding c. 1200 m. Ice‐dammed lakes and the elevations of sills are predicted for the major glacial phases and used to test the ice models. Large lakes are predicted for west Siberia at the end of the Saalian and during MIS‐5d, 5b and 4, with the lake levels, margin locations and outlets depending inter alia on ice thickness and isostatic adjustment. During the Saalian and MIS‐5d, 5b these lakes overflowed through the Turgay pass into the Aral Sea, but during MIS‐4 the overflow is predicted to have occurred north of the Urals. West of the Urals the palaeo‐lake predictions are strongly controlled by whether the Kara Ice Sheet dammed the White Sea. If it did, then the lake levels are controlled by the topography of the Dvina basin with overflow directed into the Kama‐Volga river system. Comparisons of predicted with observed MIS‐5b lake levels of Komi Lake favour models in which the White Sea was in contact with the Barents Sea.

show a dry period around 11.6 ka, steadily becoming wetter through the early Holocene. The mid-late Holocene was punctuated by millennial-scale variability, associated with the El Niño-Southern Oscillation; this is evident in the marine, coral, speleothem and pollen records of the region.