Dunkirk transgression
{{short description|Events of rising sea levels around the shores of the Low Countries in the late Roman period.}}
File:North.Sea.Periphery.250.500.jpg
The Dunkirk transgressions were tidal bulges or other sea level-related marine transgressions (risings), often heightened by river floods, affecting the North Sea and adjoining low land. Most of this land is vulnerable to such events being below or approximately at sea level. Three events and mass evacuations, at least, are seen, some stretching to land above-sea level today. The events affected the Low Countries and other land near the German Bight, Thames Estuary and The Wash. They spanned from the late Roman period until Early Medieval Europe.
Outline knowledge
The exact scale of each event with notable human impact in duration, being hypothetically determined, is debated. The cause of each is also somewhat debated, however tidal bulges have been a continuing cyclical problem of the North Sea in the centuries since.
Chronology
The main parts of the Low Countries were lightly populated until about 200 BC, when the climate and environment became more amenable to human habitation.{{Harvcolnb|Louwe Kooijmans|1974|pp=44–45}}, The Rhine/Meuse Delta.{{Harvcolnb|Ejstrud|2008|pp=17–19}}, The Migration Period. Conditions remained favourable until 250 AD, and the region became densely populated.{{Harvcolnb|Knottnerus|2001|pp=30–31}}, LANCEWAD 2001: Cultural History.{{Harvcolnb|Meier|2004|pp=55,63}}, Man and Environment in Schleswig-Holstein.
Fens below sea level were highly vulnerable to a tidal bulge until great dams and sea walls were built as shown in the North Sea flood of 1953. A series of marine transgressions followed (in specialist academic literature called Dunkirk 0 through to Dunkirk IIIb) characterised by a rising water table and floods that left layers of clay on the land. The heaviest blow came with the "Dunkirk II transgression" that began in the 3rd century and continually worsened, leaving such low land uninhabitable, {{circa}} 350–{{circa}} 700 CE. People were forced to abandon their homes and emigrate. Archaeologists find evidence for this across the Rhine/Meuse delta (Zeeland, Brabant, parts of South Holland and Limburg);{{Harvcolnb|Louwe Kooijmans|1974}}, The Rhine/Meuse Delta, PhD Thesis. Friesland;{{Harvcolnb|Louwe Kooijmans|1980|pp=106–133}}, Archaeology and Coastal Change in the Netherlands.{{Harvcolnb|Nienhuis|2008}}, Environmental History of the Rhine-Meuse Delta. Groningen;{{Harvcolnb|Knottnerus|2001|pp=29–63}}, Cultural History in LANCEWAD: Landscape and Cultural Heritage in the Wadden Sea Region—Project Report. Ostfriesland, German Friesland and the Weser/Jade estuary; and Dithmarschen, Eiderstedt and Nordfriesland.{{Harvcolnb|Meier|2004|pp=55–70}}, Man and environment in the marsh area of Schleswig-Holstein from Roman until late Medieval times.{{Harvcolnb|Meier|2013}}, Landscape and Settlement History of the North-Sea Coast of Schleswig-Holstein.
Across the Rhine/Meuse delta, the population became scant. Between the 5th and 7th centuries there were few centers of population there, and in the estuarine and peat areas no settlements have been found. The area would not be repopulated until the Carolingian Era.{{Harvcolnb|Louwe Kooijmans|1974|pp=44}}, The Rhine/Meuse Delta. Zones with river clay were so regularly deposited with alluvial silt that habitation was almost impossible between the years 250 and 650.{{Harvcolnb|Louwe Kooijmans|1974|pp=120}}, The Rhine/Meuse Delta.
Soil survey evidences and relative lack of human occupation artefacts leads scientists to theorise the Netherlands was largely underwater between the mid-third-century and 1050. This more narrow geographic range of depopulation covers the third Dunkirk Transgression period (alternatively suffixed III).{{cn|date=November 2020}}
See also
- Roman Warm Period, which lasted to about 400 AD/CE
- {{annotated link|Anglo-Saxon settlement of Britain}}
- {{annotated link|Frisii}}
References
{{reflist}}
=Works cited=
- {{cite book |last1=Ejstrud |first1=Bo |title=The migration period, Southern Denmark and the North Sea : a workbook in relationship to the Gredstedbro find |date=2008 |publisher=Maritime Archaeology Programme, University of Southern Denmark |location=Esbjerg |isbn=9788799221417}}
- {{cite journal |last=Knottnerus |first=Otto S. |title=The Wadden Sea. A unique cultural landscape |date=2001 |journal=Lancewad |issue=12 |issn=0946-896X |url=https://waddensea-forum.org/images/archive/cultural-landscape/lancewad_report_2001.pdf|archive-url=https://web.archive.org/web/20200928060442/https://waddensea-forum.org/images/archive/cultural-landscape/lancewad_report_2001.pdf|url-status=usurped|archive-date=September 28, 2020}}
- {{cite book |last1=Louwe Kooijmans |first1=L. P. |title=The Rhine/Meuse delta. Four studies on its prehistoric occupation and holocene geology |date=1974 |publisher=Leyden University Press |location=Leiden |isbn=978-90-60-21194-6 |hdl=1887/27971 |oclc=1095248}}
- {{cite book |last1=Louwe Kooijmans |first1=L. P. |chapter=Archaeology and Coastal Change in the Netherlands |editor-last1=Thompson |editor-first1=Frederick Hugh |title=Archaeology and Coastal Change: Being the Papers Presented at Meetings in London and Manchester on 27th October and 5th November, 1977 |date=1980 |publisher=Society of Antiquaries of London |isbn=978-0-500-99031-5 |url=https://books.google.com/books?id=6FKgAAAAMAAJ |language=en}}
- {{cite journal |last1=Meier |first1=Dirk |title=Man and environment in the marsh area of Schleswig–Holstein from Roman until late Medieval times |journal=Quaternary International |date=January 2004 |volume=112 |issue=1 |pages=55–69 |doi=10.1016/S1040-6182(03)00065-X|bibcode=2004QuInt.112...55M }}
- {{cite journal |last1=Meier |first1=Dirk |title=From nature to culture: landscape and settlement history of the North-Sea coast of Schleswig-Holstein, Germany |url=https://www.academia.edu/8080362 |journal=Landscapes or Seascapes? |series=Comparative Rural History of the North Sea Area |date=January 2013 |volume=13 |pages=85–110 |doi=10.1484/M.CORN.1.101549|isbn=978-2-503-54058-0 }}
- {{cite book |last1=Nienhuis |first1=P. H. |title=Environmental History of the Rhine-Meuse Delta: An ecological story on evolving human-environmental relations coping with climate change and sea-level rise |date=2008 |publisher=Springer Science & Business Media |isbn=978-1-4020-8213-9 |url=https://books.google.com/books?id=RQRdOc3iaHYC |language=en}}
External links
- {{usurped|1=[https://web.archive.org/web/20140222032735/http://www.armara.be/augustyn/SEA%20LEVEL%20RISE.pdf Sea level rise, transgression phases and storm surges in maritime Flanders to the end of the 16th century. A study of the landscape, ecology and climate from a historical point of view. Dr. Beatrijs Augustyn, (English summary of the general conclusion of the thesis by B. Augusyn, Zeespiegelrijzing, transgressiefasen en stormvloeden in maritiem Vlaanderen tot het einde van de XVIde eeuw. Een landschappelijke, ecologische en klimatologische studie in historisch perspektief, Brussel, Algemeen Rijksarchief, Studia 37-38), 1992]}} PDF