Academic Profile

Dr Winchester was awarded a D.Phil. in 1990 (thesis title: "An evaluation of lichenometry: with field studies in Lappland, Britain, and the Western Alps"), and has been affiliated to the School of Geography and the Environment as a Research Associate since 1997 and a Senior Research Associate of the School since 2002.

She began research on glacier retreat around the North Patagonian Ice field in 1991 and has continued working there to the present using both lichenometry and dendrogeomorphology to date rock surfaces exposed since the Little Ice Age.

Currently her interest has expanded to investigate the use of dendrogeomorphology as a tool for analyzing landscape processes and rates of change in temperate and arid environments. Further to this purpose, in 2002 she set up the Oxford Laboratory of Dendrogeomorphology and in 2005 ran the "20th International Dendroecological Field week" in North Devon in collaboration with the Swiss Federal Institute for Forest, Snow, and Landscape Research, Birmensdorf, Zurich, the originators of this annual event.

She is County Advisor to the Oxford Diocesan Registrar on lichen growth in the Diocesan cemeteries and graveyards.

Current Research

Madagascar, Berenty Forest Reserve: A privately-owned gallery forest beside the Mandrare River in the dry south-east, home to iconic ring-tailed lemurs, is threatened by degradation due to an invasive vine and local climatic effects linked to location and tree age. Vanessa's analysis shows that the forest can be divided into 3 zones of degeneration as defined by the Royal Botanical Gardens, Kew. Recommendations as to treatment of the degenerated zones follow the Kew guidelines.

Chilean Patagonia, North Patagonian Ice field: Vanessa took part in an expedition to study the retreat rates of Glaciar San Benito on the western side of the ice field in spring 2007. Vanessa and her colleagues have now studied eleven glaciers around the ice field between them, five on the western and six on the eastern side. These glaciers all show consistent and increasing rates of retreat and ice surface thinning since their Little Ice Age maximum was reached, according to our dating, in the 1860s.

Poland, Slowinski National Park: Sand dune movements are a matter of concern due to the current worldwide expansion of arid lands. In 2006, Dr Marcin Koprowski of the Institute of Ecology and Environmental Protection, Nicolaus Copernicus University, Torun, asked Vanessa to collaborate with him in a study investigating tree growth as an indicator of dune movements on the Baltic coast.

Peru, Machu Picchu: Tourist access to Machu Picchu, a World Heritage site, is a major concern for engineers due to frequent slope failures after heavy rain. In 2002, in collaboration with colleagues from Charles University, Prague, and assisted by Dr Bezzi from the Università degli Studi di Trento, Italy, Vanessa explored the use of tree roots and trunk tilt as indicators of slope movement frequencies along the access road to the site.

Kazakhstan, Northern Tien Shan Mountains: The valleys supplying water to the city of Almaty are prone to mudslides and debris flows. Together with Dr Passmore of the University of Newcastle-upon-Tyne and Dr Harrison of the University of Exeter, Vanessa examined the relationships between tree growth and geomorphic events to provide information on the geomorphic history and current hazard status of the valleys.

Student dissertation topics supervised by Dr Winchester

Dendrogeomorphological topics in southern Britain and Wales have included studies of slope instability; landslips; mudflows; forest disturbance by road construction, lead and toxic chemical pollution of soils. In the Karoo, South Africa, a study of willow tree growth was used to date sedimentary dams and flooding events and show erosion rates.

Lichenometric topics have included the dating of rock surfaces in relation to glacier movements or debris flows in Canada, Iceland, Scotland and Wales.

Teaching

Selected Publications

Publications are those that were listed on the old website. Publications database integration forthcoming.
  • Winchester, V., Passmore, D.G., Harrison, S., Rae, A., Severskiy, I.V., Pimankina, N.V. (in press). Dendrogeomorphological and sedimentological analysis of debris flows hazards in the northern Zailiiskiy Alatau, Tien Shan Mountains, Kazakhstan. In, Braimoh, A. (ed.) Vulnerability of Land Systems in Asia. Wiley-Blackwell. pp. 91-116. ISBN: 978-1-118-85495-2.
  • Winchester, V., Sessions M., Valdivia Cerda, J., Weundrich, O. and Nash, M. (2014) Post 1850 changes in Glacier Benito, North Patagonian Ice field, Chile. Geografiska Annaler, Series A, 96(1): 43-59.
  • Winchester, V. and Alstrup, V. (2013) Lichen hunting - mostly below - Cairn Gorm: a cautionary tale. British Lichen Society Bulletin, 112 (2): 44-50.
  • Winchester V. and Alstrup, V. (2012) A resurvey of the lichens and vascular plants of Ciste Mhearad, Scotland. Pulse: News from the the Linnean Society of London, 16.
  • Koprowski, M., Winchester, V. and Zielski, A. (2010) Tree reactions and dune movements: Slowinski National Park, Poland. Catena, 81: 55-65.
  • Passmore, D.G., Harrison, S., Winchester, V., Rae, A., Severskiy, I. and Pimankina, N.V. (2008) Late Holocene debris flows and valley floor development in the Northern Zailiiskiy Alatau, Tien Shan Mountains, Kazakhstan. Arctic, Antarctic, and Alpine Research, 40(3): 548-560.
  • Harrison, S., Glasser, N.F., Winchester, V., Haresign, E., Warren, C.R., Duller, G., Bailey, R., Ivy-Ochs, S., Jansson, K.N. and Kubik, P. (2008) Glaciar León, Chilean Patagonia: late-Holocene chronology and geomorphorphology. Holocene, 18(4): 643-652.
  • Harrison, S., Glasser, N.F., Winchester, V., Haresign, E., Warren, C.R., Duller, G., Bailey, R., Ivy-ochs, S., Jansson, K,N., and Kubik, P. (2008) Glaciar León, Chilean Patagonia: late Holocene chronology and geomorphorphology. Holocene, 18(2): 343-352.
  • Winchester, V., Gärtner, H. and Bezzi, M. (2007) Dendrogeomorphological applications. In, J. Kalvoda and A.S. Goudie (eds.) Geomorphological variations: on the occasion of the 150th Anniversary of Geography and Geoecology, Faculty of Science, at the Charles University in Prague. pp. 182-203.
  • Harrison, S., Winchester, V., Glasser, N.F. (2007) The timing and nature of recession of outlet glaciers of Hielo Patagónico Norte, Chile, from their Neoglacial IV (Little Ice Age) maximum positions. Global and Planetary Change, 59: 67-78.
  • Harrison, S., Glasser, N.F., Winchester, V., Haresign, E., Warren, C.R. and Jansson, K.N. (2006) A glacial lake outburst flood associated with recent mountain glacier retreat, Patagonian Andes. Holocene, 16(4): 611-620.
  • Winchester, V., Klemme, B., and Koprowski, M. (2006) Ringing the Changes: a study of plants and dune movements at Braunton Burrows. Sanctuary: the Ministry of Defence Conservation Magazine, 35: 56-57.
  • Harrison, S., Winchester, V., Warren, C.R. and Passmore D.G. (2005) Quantifying rates of paraglacial sedimentation: an example from Chilean Patagonia. Zeitschrift für Geomorphologie, 49(3): 321-334.
  • Winchester, V., Harrison, S., Bailey, R. (2005) A 2.5 ka luminescence date for a terminal moraine in the Leones Valley, Southern Chile. Journal of Glaciology, 51: 186-188.
  • Winchester, V., Viles, H., and Gärtner, H. (2005) Fieldtrip report: 20th International Dendroecological Field Week. 28th August - 3rd September 2005. Geophemera, 96: 25-27.
  • Winchester, V. (2004) Lichens. In, S. Harrison, S.J. Pile, and N.J. Thrift (eds.) Patterned Ground: Ecologies of nature and culture. Reaktion Press. pp. 271-273.
  • Glasser, N.F., Harrison, S., Winchester, V., and Aniya, M. (2004) Late Pleistocene and Holocene paleoclimate and glacier fluctuations in Patagonia. Global and Planetary Change, 43: 79-101.
  • Winchester, V. (2004) Dendrochronology. Dendrogeomorphology. Lichenometry. In, A.S. Goudie (ed.) The Encyclopedia of Geomorphology. Routledge. pp. 618-620.
  • Winchester, V. (2003) The peripatetic hedge: A case for dendrochronological dating. Science and Justice, 43(1): 23-28.
  • Winchester, V. and Sjöberg, R. (2003) Lichenometry and beach ridge formation at Bådamalen on the North Bothnian coast, Sweden. Zeitschrift für Geomorphologie, 47(4): 485-498.
  • Winchester, V. and Chaujar, R.K. (2002) Lichenometric dating of slope movements, Nant Ffrancon, North Wales. Geomorphology, 47(1): 61-74.
  • Passmore, D.G., Harrison, S., Rae, A., Winchester, V., New, M., Severskiy, I. and Pimankina, N. (2002) Recent historic debris flows and valley floor development in the Northern Zailiiskiy Alatau, Tian Shan mountains, Kazakhstan. In, Schröder, H., Harrison, S., Passmore, D.G., Severskiy, I., Veselov, V. and Glazirin, G. (eds.) Assessment of renewable ground and surface water resources and the impact of economic activity on runoff in the basin of the Ili River, Republic of Kazakhstan. Kazakh Academy of Sciences, Almaty. pp. 288-307.
  • Harrison, S.H., Passmore, D.G., Severskiy, I., Winchester, V. and Rae, A. (2001) Late Holocene mudflows in a high mountain permafrost environment, Northern Zailiiskiy Alatau, Tian Shan mountains, Kazakhstan. Abstract Proceedings of 2001 Association of American Geographers. New York.
  • Winchester, V., Harrison S., Warren, C.R. (2001) Recent Retreat Glaciar Nef, Chilean Patagonia, Dated by Lichenometry and Dendrochronology. Arctic, Antarctic and Alpine Research, 33(3): 266-273.
  • Warren, C.R., Benn, D., Winchester, V., Harrison, S. (2001) Buoyancy-driven lacustrine calving, Glaciar Nef, Chilean Patagonia. Journal of Glaciology, 47(156): 135-146.
  • Harrison, S., Warren, C.R., Winchester, V. and Aniya, M. (2001) Onset of rapid calving and retreat of Glaciar San Quintin, Hielo Patagónico Norte, Southern Chile. Polar Geography, 24(1): 54-61.
  • Bridge, M.C. and Winchester, V. (2000) An evaluation of standard oak tree growth in Ruislip Woods, West London. Botanical Journal of the Linnean Society, 134: 61-71.
  • Winchester, V. and Harrison, S. (2000) Dendrochronology and lichenometry: an investigation into colonization, growth rates and dating on the east side of the North Patagonian Icefield, Chile. Geomorphology, 34(1-2): 181-194.
  • Harrison, S. and Winchester, V. (2000) Nineteenth and Twentieth-Century glacier fluctuations and climatic implications in the Arco and Colonia valleys, Hielo Patagonico Norte. Arctic, Antarctic and Alpine Research, 32(1): 55-63.
  • Winchester, V., Harrison, S., Washington, R. and Warren, C.R. (1999) Austral summer of 1998: Observations on El Niño and the North Patagonian Icefield. Weather, 54(9): 287-293.
  • Harrison, S., and Winchester, V. (1998) Historical fluctuations of the Gualas and Reicher Glaciers, North Patagonian Icefield, Chile. The Holocene, 8(4): 481-485.
  • Winchester, V., and Harrison, S. (1997) Estimate of ice surface velocity over a four-year period on Glaciar Arenales, Hielo Patagónico Norte, Southern Chile. Correspondence. Journal of Glaciology, 43(144): 370-372.
  • Harrison, S., and Winchester, V. (1997) Age and nature of paraglacial debris cones along the margins of the San Rafael Glacier, Patagonian Chile. The Holocene, 7(4): 481-487.
  • Winchester, V. and Harrison, S. (1996) Recent oscillations of the San Quintin and San Rafael Glaciers, Patagonian Chile. Geografiska Annaler, 78A(1): 35-49.
  • Harrison, S., Anderson, E., and Winchester, V. (1996) Large boulder accumulations and evidence for permafrost creep, Great Mis Tor, Dartmoor. In, D.J. Charman, R.M. Newnham, and D.G. Croot (eds.) The Quaternary of Devon and East Cardwell: Field Guide. Quaternary Research Assoc., London: pp102-105.
  • Warren, C.R., Glasser, N.F., Harrison, S., Winchester, V., Kerr, A., and Rivera, A. (1995) Characteristics of tide-water calving at Glaciar San Rafael, Chile. Journal of Glaciology, 41(138): 273-289.
  • Winchester, V. and Harrison, S. (1994) A development of the lichenometric method applied to the dating of glacially influenced debris flows in Southern Chile. Earth Surface Processes and Landforms, 19: 137-151.
  • Winchester, V. (1993) Lichenometry. In, P. Kearey, P.A. Allen, A.M. Evans, A.S. Goudie, A. Hallam, R.G. Park, R.S. Thorpe, and D.J. Vaughan (eds.) The Encyclopedia of the Solid Earth Sciences. Blackwell Scientific Publications. pp. 394.
  • Winchester, V. (1988) An assessment of lichenometry as a method for dating recent stone movements in two stone circles in Cumbria and Oxfordshire. Botanical Journal of the Linnean Society, 96: 57-68.
  • Winchester, V. (1984) A proposal for a new approach to lichenometry. British Geomorphological Research Group, Technical Bulletin 33, Shorter Technical Methods V: 3-20.