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Behre, 2004, Abb. 2 (German North Sea coast):

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Klaus Eckart Puls, 2008 (part of Behre's sea level graph, see previous two images):

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See also the critical comments on Behre's sea level curve for the southern North Sea (2003, 2004, 2007) by Baeteman, Waller and Kiden (2011) and Bungenstock and Weerts (2010, 2012), and Behre's response (2012).

Baeteman, Waller and Kiden (2011) conclude that the high-amplitude middle and late Holocene sea-level fluctuations identified by Behre (2003, 2007) are highly unlikely to be real features of the sea-level history of the southern North Sea.

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North Sea coast of the Netherlands and Belgium

Relative sea level rise during the Holocene along the North Sea coast (TNO-NITG, 2003).

An old question (1950's) is, whether the succession of marine clay and peat layers in the Western part of the Netherlands and Belgium is an indication of fluctuations of sea level during the second half of the Holocene (Atlanticum-Subboreal-Subatlanticum). These clay and peat layers were considered in the past as reflecting phases of transgression and regression of the sea. In 1954 a special issue of the Dutch journal "Geologie en Mijnbouw" appeared about "Quaternary changes in level especially in the Netherlands". Below are two figures, viz. by Van Straaten en Bennema, taken from this issue. They show that already in 1954 the first 'smoothers' and 'wigglers' regarding sea level rise were present.





Recently, as more C14-datings of the marine clay and peat layers became available at more locations in the Netherlands and Belgium, it has become clear, that no specific periods or phases of trans- and regression of the sea can be recognized that have occurred synchronously along the entire Dutch and Belgian coast (the so-called Calais and Duinkerke Deposits). And that therefore these marine clay and peat layers can no longer be considered as evidence of fluctuations of sea level along the Dutch and Belgian coast during the Atlanticum-Subboreal-Subatlanticum. In fact, in the Netherlands no evidence at all for fluctuations of sea level rise during the Atlanticum-Subboreal-Subatlanticum has been found so far. See:
Weerts, H.; Cleveringa, P.; Westerhoff, W.; Vos, P. (2006): Nooit meer: afzettingen van Duinkerke en Calais, Archeobrief (Methoden en Technieken), 28-34. Stichting voor de Nederlandse Archeologie (SNA).

De Boer, G., 2006. Het fysisch-geografisch onderzoek en de ontstaansgeschiedenis van westelijk Zeeuws-Vlaanderen: een status quaestionis. Tijdschrift voor Waterstaatsgeschiedenis 14 (2005); webversie 2006, pp. 48-58.

De Groot, Westerhoff, and Bosch, 1996 wrote about this in 1996 (pp. 69-70):
"In the Netherlands, the rate of relative sea-level rise during the last 2000 years is poorly known, mainly because of the lack of well-datable material associated with sea-level markers concerning that periode."
"Over the last 2000 years there has been non coastal progradation in the western part of the Netherlands and no palaeo sea-level markers were formed."

Here is their Figure 6 of the palaeo Mean High Water (MHW) trend over the last 2000 years on the Frisian Islands:

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Masters, 2009 (Based on Grinsted et al. 2009):

Figure 1. Global sea level from 200 A.D. to 2000, as reconstructed from proxy records of sea level by Moberg et al. 2005. The thick black line is reconstructed sea level using tide gauges (Jevrejeva, 2006). The lightest gray shading shows the 5 - 95% uncertainty in the estimates, and the medium gray shading denotes the one standard deviation error estimate. The highest global sea level of the past 110,000 years likely occurred during the Medieval Warm Period of 1100 - 1200 A.D., when warm conditions similar to today's climate caused the sea level to rise 5 - 8" (12 - 21 cm) higher than present.

Image credit: Grinsted, A., J.C. Moore, and S. Jevrejeva, 2009, "Reconstructing sea level from paleo and projected temperatures 200 to 2100 AD", Climate Dynamics, DOI 10.1007/s00382-008-0507-2, 06 January 2009.

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Gonzalez et al., 2009 (Mississippi Delta):





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Kemp et al., 2010 (US Atlantic coast):

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Rahmstorf, S., 2011. 2000 years of sea level (North Carolina, US Atlantic coast):

"Good data on past sea levels is hard to come by. Reconstructing the huge rise at the end of the last glacial (120 meters) is not too bad, because a few meters uncertainty in sea level or a few centuries in dating don’t matter all that much. But to trace the subtle variations of the last millennia requires more precise methods. Andrew Kemp, Ben Horton and Jeff Donnelly have developed such a method. They use sediments in salt marshes along the coast, which get regularly flooded by tides. When sea level rises the salt marsh grows upwards, because it traps sediments. The sediment layers accumulating in this way can be examined and dated. Their altitude as it depends on age already provides a rough sea level history. But then comes the laborious detail. Although on average the sediment buildup follows sea level, it sometimes lags behind when sea level rises rapidly, or catches up when sea level rises more slowly. Therefore we want to know how high, relative to mean sea level, the salt marsh was located at any given time. To determine this, we can exploit the fact that each level within the tidal range is characterized by a particular set of organisms that live there. This can be analyzed e.g. from the tiny shells of foraminifera (or forams for short) found in the sediment. For this purpose, the species and numbers of forams need to be determined under the microscope for each centimeter of sediment. To get a continuous record of good resolution, we need a site with a rapid, continuous sea level rise. Kemp and colleagues used salt marshes in North Carolina, where the land has steadily sunk by about two meters in the past two millennia due to glacial isostatic adjustment. Thus a roughly 2.5 meters long sediment core is obtained. The effect of land subsidence later needs to be subtracted out in order to obtain the sea level rise proper."

Figure caption. Sea level evolution in North Carolina from proxy data (blue curve with uncertainty range). Local land subsidence is already removed. The green curve shows a reconstruction based on tide gauges from around the world (Jevrejeva et al. 2006, 2008). The red curve shows results from a simple model connecting global temperature with sea level. For the last millennium the sea level curve follows what can be expected from temperature – the two independent reconstructions thus mutually reinforce each other by their consistency. Before 1000 AD there is a discrepancy: warm temperatures in the reconstruction used would lead to rising sea level, but the sea level reconstruction is flat. However, temperature data from before 1000 AD are sparse and less reliable, and lowering temperatures in this period by only 0.2ºC removes the discrepancy. Thus, a possible explanation for the discrepancy is that the temperature reconstruction is a little too warm before 1000 AD.