Probing the depths of Windermere
University of Southampton doctoral researcher Helen Miller has come up with new insights into England’s largest lake, thanks to a pioneering underwater study.
As part of her PhD research on Windermere, she has used sophisticated survey equipment on the British Geological Survey’s catamaran White Ribbon to produce a detailed picture of the lake bed, which was originally a glacial river valley. The computer-generated mapping uses colourful images to show the lake’s depths and illustrate how they have changed since the last Ice Age. This is the first scientific underwater exploration of Windermere - the last survey of the lake was carried out during the 1930s by the Admiralty.
The Lake District National Park has already used the pictures on information boards and Helen has spoken about her research to local groups and on BBC Radio Cumbria; her work has also featured on a Planet Earth podcast and in the Westmorland Gazette.
The multibeam bathymetric (echo-sounding) survey of Windermere has given scientific researchers and local people alike a fascinating and accurate map of the lake bed as if it contained no water. It shows moraines and other glacial remains and even old shipwrecks. Helen has also taken ten metre long sediment core samples from beneath the lake bed which may hold vital information about global climate patterns. Initial analysis has uncovered evidence of pollution involving heavy metals such as lead, zinc and copper over the last 500 years but much more work remains to be done on the cores.
“Surveying out on the lake was a wonderful experience,” she says. “The equipment revealed for the first time what is really going on beneath the surface and we gained a great deal of information that will be tremendously useful for future researchers.”
In further results of her research, the underwater cameras revealed that gravel beds used as spawning grounds for the Arctic charr are silting up. The charr is a species of fish which has lived in the lake since the last Ice Age but may now become endangered. Helen has worked with Dr Ian Winfield of the Centre for Ecology and Hydrology (CEH) at Lancaster University on the research; he says the findings have given them a much more detailed picture of the lake. Work is underway to stop the gravel silting up. Jon Bull, Professor of Geology and Geophysics at Southampton says: “This is a really good example of bringing scientists from multiple disciplines (biologists, geologists, geochemists and geophysicists) together to understand processes operating within England’s largest lake.”
Helen became interested in ocean and Earth science while working for her first degree, BSc in Geography, at the University of Edinburgh. During her undergraduate studies, she spent a year at the University of Auckland in New Zealand and enjoyed learning more about the southern ocean. Helen then took a masters degree in Oceanography at the National Oceanography Centre Southampton and worked for two years at an oil spill response company in the Netherlands before returning to study at the University of Southampton in 2010 after hearing of an opportunity from her former academic supervisor.
She has worked with the British Geological Survey (BGS) and the Centre for Ecology and Hydrology at Lancaster University on this research for her PhD which is funded by the BGS, the Environment Agency and the University of Southampton. Her supervisors are Professors Jon Bull and Justin Dix at the University of Southampton and Dr Carol Cotterill at the BGS.
http://www.bgs.ac.uk/research/highlights/2013/lakeWindermere.html