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Visit Our Centre

EFC Centre at Wat Tyler Country ParkOur centre is available for visits on a pre-booked basis on Wednesdays between 10am - 4pm. The Club’s activities and displays are also usually open to the public on the first Saturday of the month 11am - 4pm.

About us

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Purfleet-on-Thames

previous pageClimate Change Years ago 300,000 200,000 100,000 0 Devensian No humans in Britain ‘Purfleet people’ ‘Aveley people’ ‘Purfleet’ Warm interglacial Cold glacial ‘Aveley’ R S R S R S R Ipswichian Civilization MIS 10 8 6 4 2 Holocene 11,700y Temperatures during the latest part of the Ice Age In Britain the Ice Age started 2.6 million years ago and has experienced over 50 cycles of cold (glacial) and warm (interglacial) climates, some warmer than the interglacial we currently are in. These cycles are caused by variations of the earth’s orbit in relation to the sun. It is only in the last 800,000 years that the cold stages were cold enough for glaciers to reach our latitudes. Since then the cycles have taken about 100,000 years, comprising a trough of a few thousand years. This was followed by a rapid rise in temperature taking only a few thousand years to an interglacial peak (R), again lasting a few thousand years. Then there was a long slow decline taking 80 thousand years or more to the next cold trough (S). Cold Stages The cold stages led to the development and expansion of glaciers in the polar regions, causing a drop in sea-level as rain and snow became trapped on land as ice instead of returning to the sea. Britain became linked to the continent. With the sea bed now dry land, humans and animals were able to migrate southwards as the climate deteriorated and the vegetation declined. With the change of climate, and the decline in vegetation, the Thames changed to a multi-channel braided pattern, with wide, shallow beds dominated by gravels laid down by floods as the ice and snow on land melted each spring. Warm Stages The rapid climatic recovery from the cold stages meant that humans and animals had to migrate back to Britain fairly quickly before sea-level rose again, but even so, people from as far away as southern Europe were able make the migration. With the recovery, vegetation returned, protecting the land from erosion so less water and gravel reached the Thames and it switched to a sinuous-meandering pattern, similar to today. N. McPhee (Alaska) Google Earth (W. London 2020)next page