Page 6 - Sea-level change_2004

ARTICLE IN PRESS
1974 K. Lambeck, A. Purcell / Quaternary Science Reviews 24 (2005) 1969–1988

Fig. 1. (a) Relative sea-level change between 12 ka andpresent for the melting of the nominal ice sheets on a rigidearth. The equivalent sea level at
12 ka BP is 54 m andacross the region water levels lie above this level because of the direct gravitational attraction of the water by the northern ice
sheets. (b) The glacio-isostatic contribution Dz I g at 12 ka from the decay of the northern European ice for the nominal earth model. (c) Same as (b)
but for the North American ice sheet. (d) Same as (b) but for the Alpine deglaciation. (e) The glacio-isostatic contribution at 12 ka BP from the total
global ice sheets, including Antarctica and mountain glaciers, (f) Same as (e) but for 6 ka BP. In all model predictions, melting ceased at 6.8 ka BP.
The black contours denote negative values, white contours positive values, and the zero contour is given by the dashed white line. In (d) the contour
interval is 1.25 m andthe maximum value is 11 m. (At 6 ka BP, the maximum value for the central Alpine reboundis 3 m.) A small peripheral
bulge develops around this alpine load with maximum deflection in central Italy of about 1 m at 12 ka (and 0.25 m at 6 ka BP).

The total Dz I-g for all ice sheets, including an that by 6 ka small positive values for Dz I-g are predicted
Antarctic contribution, is illustratedin Figs. 1e andf for the far-eastern Mediterranean where the long
for 12 and6 ka, respectively. For the former epoch, the wavelength direct attraction is of larger amplitude than
change across the region from the glacial reboundalone the deformational contribution. Other than here, the
ranges from about 3 m in the eastern Mediterranean to glacio-isostatic effect across the region is mostly one of a
about 12 m for the northern Adriatic Sea and the rising level in Late Holocene time, even when ocean
French Mediterranean coast. Under the influence of the volumes have remainedconstant since 6.8 ka BP.
Alpine rebound, the gradient changes sign in both the
northern Adriatic Sea and the Gulf of Genoa, and the 3.3. Hydro-isostatic contribution
largest magnitudes for Dz I-g actually occurs in the
central northern Adriatic. The pattern illustrated in Figs. 2a andb illustrate the hydro-isostatic contribu-
Figs. 1e andf persists for much of the Holocene except tion Dz I-h across the region at 12 ka BP. Two results are