New stratigraphic data collected from six sites in the Humber estuary establish a record of Holocene relative sea-level (RSL) change, and enable testing of four possible causes ofrapid coastal change: sea-level rise, changes in sedimentation, storm-surge history, and human impact. Mean high water of spring tides (MHWST) in the Humber rose from c. -9 m OD at 7500 cal. yrs BP to 0 m OD by 4000 cal. yrs BP, at an average long-term rate of c. 3.9 mm yr'. After this, the rate of rise gradually decreased to c. 1 mm yr'. Discrete episodes of rapid RSL rise are not identified although their absence may reflect limited data availability. However, we do observe two episodes of rapid coastal change in the Humber estuary. The first occurs between c. 3200 and 1900 cal. yrs BP, as marine conditions expand to their Holocene maximum and then contract. This pattern of coastal development differs from that in the East Anglian Fenlands, suggesting local processes control sedimentation at one or both of these sites. The second period of rapid change relates to a well-documented episode of increased storm surge activity in the Humber estuary and elsewhere in the UK and the North Sea region between c. 700 and 500 cal. yrs BP. Coastal development during this period varies considerably with erosion, accretion and flooding in different parts of the estuary system. Finally, we examine evidence for accelerated sediment delivery to the Humber estuary due to woodland clearance and prehistoric agriculture from 5700 cal. yrs BP onwards. Maximum sediment input is likely at c. 3200 to 1900 cal. yrs BP; a period which tentatively correlates with an episode of estuary infilling and shoreline advance.

Novel prospects for the Maldives do not include a condemnation to future flooding. The people of the Maldives have, in the past, survived a higher sea level of about 50 -60 cm. The present trend lack signs of a sea level rise. On the contrary, there is firm morphological evidence of a significant sea level fall in the last 30 years. This sea level fall is likely to be the effect of increased evaporation and an intensification of the NE-monsoon over the central Indian Ocean. D

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The Holocene sequence of the Humber Estuary displays a wide range of sediment types within which the preservation of microfossils is highly variable. Its evolution has been reconstructed using a range of environmental proxies with chronological control provided by more than 90 radiocarbon dates. Results are presented of diatom analyses from three cores typical of the inner, middle and outer estuary (HMB20, HMB7 and HMB12) and of three cores that illustrate the role of organic deposits (peats) and their associated pollen (HMB 13, HMB12 and the Ancholme Valley) in the definition of sea-level index points. The reconstruction of relative sea-level change shows a rapid rise in the early Holocene, followed by a reduced rate of rise in the mid-late Holocene. This reconstruction, together with information on the pre-Holocene surface and the different palaeoenvironments from the cores have been integrated within a geographical information system and then interpreted to yield a series of palaeogeographical maps of the Humber at 1000-year time slices between 8 and 3cal. kaBP. The marine transgression progressed up the estuary after 8cal. kaBP, reaching the inner estuary by 6 cal. ka BP. The expansion of intertidal environments probably reached its maximum around 3cal. ka BP. Changes since 3 cal. kaBP are described using archaeological and historical records. Tidal asymmetry is a major controlling factor on the balance of sediment accretion and erosion in the estuary. Sedimentary and bathymetric evidence suggests a damped oscillation between flood and ebb asymmetry in the Humber over the Holocene period. Such a conclusion would be of great importance to estuarine managers and users since it could be used to predict the future development of the estuary.

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